Manie's Microcruiser [Archive] - Page 3

Manie B

01-30-2012, 03:55 AM

Ok so here I go and launch the boat?

Firstly at home I test and re-test the motors
check and re-check everything
check and re-check everything again

load a mountain of food and booze
fill up the drinking water
petrol in both tanks
and off I go

Arrived at the dam at 09h30 on Saturday morning. What a pleasure, the trailer works fantastic, the boat is easy to launch all by myself, alone, no audience, no intereference, I can CONCERTRATE on all the zillions of things that can and WILL go wrong. The boat is beautifull, inside and out.
So off I go. The motor started 2 pulls, easy no problem.

10 minutes out of the harbour Mr. Murphy Law pays me a visit and the motor cuts out. Stone dead - kaput.
Sheeeeat what the "f" now? Pull and pull. Curse all above and below, enough bad language to go around to make Blackbeard and his crew look like beginners, every cloud disappears and the sun beats down on me like a furnace from hell.

So here I go, no flies on me, I know and work on fourstroke engines for a living. Into the shallows, drop the anchor out nicely and now I can stand behind the boat with the motor just off the sandy bottom. Bow into the waves and wind, me protected at the stern. All good.
Strip the carb off, clean and put back.
Still nothing.

FOUR hours later, in the hot BLAZING SUN, STILL NOTHING.
Now i am cursing sooo much that the heavens cloud over BLACK and I realise I am beaten. Time to give it up. My back aches, my shoulders are screaming with pain when I try and pull the rope just that once more. So now I have to head back into the wind with the tiny 30 lbs Minnkota. It barely makes it, speed probably a half a knot, if that. So now here is the next worry, will the battery last?

Anyway I load up and head back home. Phone the missus and bemoan my sorry lot, and I will never be sure but it almost sounded like she could be smiling? Now I am realy peed-off. On the way home I drive thru a thunder storm the likes of which I have not experienced ever.

Get back home, park off and grab the first beer for the day. Spent the Sunday in bed sulking, feeling sorry for myself and my aching body.

Right, so off to the agents this bright and sunny Monday morning first thing, strip the carb, its clean, 2 pulls and she runs like a dream. Two pulls WTF ?? am I losing it? am I going mad, what the hell is going on here? I am at a loss for words.
Mr. Muphy Law you won round one, but the next round I am gonna stuff your head up your backside so deep its gonna come out your belly button!

So for the ten minutes I spent on the boat - its lovely
For the two minutes I spent INSIDE getting the tools, its great.
Lovely to be back on the water, 110 % happy with the boat
wish I had a mast and sails, but that is next on the list

So was the first launch good?
with hindsight yes, all my crazy design work of boat and trailer is spot on.
Dirt in the BRAND NEW motor and fuel tanks, who knows. The motor has been lying here for well over a year now AND I did test it properly before I left.

Murphy's Law
what can I say :eek:

So all I was able to do was have a glass of WATER on the boat - how crazy is that?

Wynand N

01-30-2012, 04:39 AM

should have taken me with you.....:D I work on two stroke boat engines for a living at home....

01-30-2012, 05:16 AM

Hey, it floats! Sorry to hear about you're motor woes.

It wasn't overly important, but the "bunks" I was refering to is that part of the boat trailer that supports the boat.

Manie B

01-30-2012, 05:26 AM

that part of the boat trailer that supports the boat.

that is a high density foam manufactured by a company called Sondor here by us
must say I am very pleased with it, really works well
the boat sits nice and soft on its "pillows"

Wynand, sorry my mate, but it was a lousy day
as soon as I have built up the confidence we can go for a spin and a beer
as you know I was born a "worrier" nervous about every little detail
lousy to have that gene

masalai

01-30-2012, 06:05 AM

I think I know what it was - - The boat was left alone on the hard concrete ramp and "spat the dummy" :o :D :D - - Give it a kiss and one from me - LOOKS ABSOLUTELY FANTASTIC... - Oh and you should have had Wynand there as moral support - He is a friend no? :o - NEXT TIME EH? - - - (Mine punishes me whenever I leave CNO unattended too long...)

Manie B

01-30-2012, 06:35 AM

you should have had Wynand there as moral support

problem is that it would have been terrible for Wynand to drive all that way for a mornings nonsence :(

then I would have been in the poooh pooooh ;)

masalai

01-30-2012, 06:47 AM

But he may have felt useful, and helped you drink all that beer you brought but did not drink till you despondently got home, and the engine would have worked because you did not give your boat reason to "spit the dummy and have the engine fail" :D :D :D BOATS have FEELINGS too you know ? ? ? ? - What is her name ?????????????????????? In the water must have a name !!!!!!!!!!!!

hoytedow

01-30-2012, 06:51 AM

You could call her NCO (Not Coconut Oil)!

Doug Lord

01-30-2012, 08:03 AM

To hell with the motor-congratulations on the launch!!!

Manie B

01-30-2012, 08:12 AM

Her name is

fargo

now isn't that ironic :D

didn't get far at all

hoytedow

01-30-2012, 08:14 AM

Her name is

fargo

now isn't that ironic :D

didn't get far at allI like that name. She will.

Dirteater

01-30-2012, 12:08 PM

she looks just great on the water Manie, nice color :cool:
hey... look at it this way,
no problems with the boat really, just the *^*$$%%! motor.
(blue streak here). :D
looking forward to hearing of your well desearved time on her.
which hopefully will be your next time out.

troy2000

01-30-2012, 12:44 PM

Gratz on getting the bottom wet, Manie. I've been watching and waiting, along with a whole lot of other people from all over the world... :)

Angélique

01-30-2012, 05:36 PM

Hi Manie,

I'm happy for you about the boat :), sorry about the motor . . . . :(

Here's the (biased?) opinion of a Dutch in- & outboard repairer (http://www.bbmreparatie.nl/) who works on . . . .

• Evinrude • Johnson • Yamaha • Mercury • Tohatsu • Volvo • Yanmar • Mariner • Suzuki • Honda • Vetus • OMC •

but excludes Parsun from his services, his Parsun advice . . . . (http://www.bbmreparatie.nl/advies.php)Over Parsun buitenboordmotoren.

Veelal wordt onze mening gevraagd over Parsun buitenboordmotoren en de aantrekkelijke aanschaf prijzen.

Vanwege onze eerdere ervaringen zijn wij gestopt met het repareren van Parsun buitenboordmotoren.

Onze mening is als volgt...

Een Parsun buitenboordmotor beschikt niet over een origineel Yamaha motorblok zoals veelal wordt beweerd.

Soms is het lastig om aan onderdelen te komen en veel reparateurs willen niet aan Parsun beginnen.

Daarnaast produceert een Parsun buitenboordmotor meer geluid bij hogere toerentallen.

Maar ja..

wat verwacht je voor een lagere aanschafprijs in vergelijking met een gerenommeerd merk.

Het advies is om toch te kiezen voor een merk als Yamaha, Mercury, Evinrude, Suzuki of Honda.

Gerenommeerde merken dalen minder snel in waarde en er zijn ruim voldoende onderdelen leverbaar.

Wij zijn zelf erg te spreken over Yamaha en de latere fourstroke modellen van Honda. (v/a 2008)

Wat zou tweedehands beter te verkopen zijn... een Parsun of een Yamaha?

Ga de biedingen maar eens vergelijken op http://www.marktplaats.nl (http://kopen.marktplaats.nl/watersport-en-boten/buiten-en-binnenboordmotoren/c980.html)

Met onze jarenlange ervaringen in het uitvoeren van reparaties en onderhoud,

verlenen wij alleen garantie op merken waar wij zelf volledig achter staan.

Betrouwbaarheid op open water is hier belangrijker dan de prijs !!

-----------------------------------------------------------------
Google translation:
---------------------

About Parsun outboards.

Often is asked our opinion about Parsun outboards and their affordable purchase prices.

Because of our previous experiences, we stopped repairing Parsun outboards.

Our opinion is as follows ...

A Parsun outboard does not have an original Yamaha engine as often is claimed.

Sometimes it is difficult to parts, and many repairers do not want to start Parsun.

Parsun outboard also produces a more sound at higher speeds.

But yeah ..

what do you expect for a lower price compared to a reputable brand.

The advice is still to choose a brand such as Yamaha, Mercury, Evinrude, Suzuki and Honda.

Renowned brands decline less rapidly in value and there are plenty of parts available.

We are very pleased with Yamaha and the subsequent four stroke models from Honda. (v / a 2008)

What would be better to sell second hand ... Parsun one or a Yamaha?

Go compare the bids at http://www.marktplaats.nl (http://kopen.marktplaats.nl/watersport-en-boten/buiten-en-binnenboordmotoren/c980.html)

With our years of experience in performing repairs and maintenance,

We give notice that we only guarantee them full support.

Reliability on open water is more important than price!

Don't know them myself, maybe someone else can find better references for Parsun . . ?

Good luck !
Angel

rwatson

01-30-2012, 05:57 PM

I had a brand new 6hp mercury stop on a maiden voyage, that then took me 6 hours to sail home in a adverse wind up a busy shipping channel.

The cause ?

The "man overboard" switch (that you attach to a cord that attaches to you) had been manufactured with a too long plastic "tongue", so it failed to disengage when the "man overboard pin" was in place.

The bloody motor thought I had fallen out !!!

It will be something like that, you can bet.

Angélique

01-30-2012, 07:01 PM

Good tip to look at Watson http://www.boatdesign.net/forums/images/icons/icon14.gif, I hope it's just that :)

From Holland . . . Brand new Parsun F5BM - 5Hp.

http://www.boatdesign.net/forums/images/editor/youtube.gif Alex zijn Chinese buitenboordmotor (http://youtu.be/xGWKK7JQfWw), see also the comments in Dutch and English, I know Manie can read both . . .
- - - Alex's Chinese outboard

Cheers,
Angel

01-30-2012, 07:35 PM

The motor problemsl. Argh!!!

Most likely you're familiar with Gasoline Engines 101, but here goes. The engine triangle: spark, fuel and air. Loose one, you lose it all. I would almost guess it was some form of fuel starvation. Is the tank properly vented? Checking spark will be a tough one with a pull start. Pull the plug wire, stick a screwdriver in the plug hole, place the screwdriver shaft close to ground (cylinder head etc.) and pull on the starter. You should get a spark from the shaft to ground. A screwdriver with an insulated handle is the prefered option.

The trick now is to go out and strand yourself again with an obstinate engine that refuses to run. :D Its rather difficult to troubleshoot a functioning engine. Be sure to bring lots of beer and ice. :cool:

Angélique

01-30-2012, 07:37 PM

Parsun review (http://parsunreview.blogspot.com/): I'm sorry, didn't find a positive Parsun reference yet . . . :confused:

Wynand N

01-30-2012, 10:49 PM

Manie's problem pointing to fuel starvation. Have this problem all the time with engines I service, especially on Yamaha which I sort of specializes in but am not a Yammie dealer. I am a Tohatsu agent.

Usually when a motor is left for a long time without usage the residual two stroke oil will turn thick and sticky when the petrol evaporated and clogs up carburetor jets and in some case the needle ad seat unit.
The emulsion tube (main jet) is usually the culprit and few people are aware of this particular jet and the fact it can be removed - it has a few very small holes that clogs easily. It is the little brass tube that protrudes into the carburetor throat where the fuel is sucked through to enter the engine.

The problem with this problem is the motor will start and idle easily, even run with a bit of throttle given slowly but when opening the throttle it will bogs down. Sometime it will suck in some of the sticky dried old two stroke residue in the carb sump and this will clogs things up and dead motor the result.
A simple carburetor strip down and cleaning and the sun shines brighter again:cool:

BTW, the Parsun sells in big numbers here and never really heard of a bad experience yet.
The two stroke models are based on the Yamaha Enduro two stroke range (2007 and newer) and all parts in the Endurance are interchangeable with the Parsuns in its given HP range except for the CDI unit.

Angélique

01-30-2012, 11:12 PM

I think Manie has a Parsun F5BM which is a four stroke ;)

Cheers,
Angel

Wynand N

01-30-2012, 11:36 PM

my bad, thought he had a two stroke :o

Angélique

01-30-2012, 11:46 PM

Found this by KenTheCanadian on

Yachting and Boating World Forums > Practical Boat Owner's Reader to Reader > Link (http://www.ybw.com/forums/showthread.php?t=279091)Fuel Line Blocking on Parsun 4-stroke Outboards (F5BM)

Here's the solution for a known problem with the 5 hp (F5BM) Parsun 4-strokes.

The fuel filter inside the internal fuel tank comes loose and blocks the outflow of fuel. It can leave you stranded, as I found out. The motor simply won't start because it can't get fuel.

If you want to know more, there's a service bulletin here:

http://www.mticanada.ca/products/parsun_en.html

Also, there may be damage to the gas valve seal on pre-2009 models if you've used fuel containing ethanol.

I wanted to put this notice up on the Internet in hopes that someone else won't take as long to Google the solution as I did.

Ken

http://www.boatdesign.net/forums/images/attach/pdf.gif PDF format version of the 201 Parsun flyer. (http://www.mticanada.ca/pdf/ParsunDepliantEN110419.pdf)

http://www.boatdesign.net/forums/images/attach/pdf.gif PDF service bulletin about filter on 5 hp motors. (http://www.mticanada.ca/pdf/ParsunBulletinPA01_2100212.pdf)PROBLEM (#1)
Due to engine vibrations, the filter, under the gas tank, can move down in the gasoline tube in some cases.
It may reduce the gasoline flow and sometimes it can stop the engine.

SOLUTION (#1)
In order to fix the problem, remove the tube from the tank and push the filter inside the tube.*
Then, set the tube in place.

* - I'll guess this must be . . . ‘‘push the filter inside the tank’’ . . . but not sure as I haven't seen it for real.

- - And secure the filter wherever it belongs . . :idea:

http://www.boatdesign.net/forums/images/attach/pdf.gif PDF service bulletin about 5 hp motors gas valve seal (models prior to 2009). (http://www.mticanada.ca/pdf/ParsunBulletinPA02_100212.pdf)PROBLEM (#2)
We noticed that the seal of the gas valve is deformed and reduced gasoline flow. We mentioned this problem to
Parsun Company. Since March 2009, the material of this seal has been changed and is now resistant to ethanol and
gasoline blend E15 (15% ethanol and 85% gasoline).

SOLUTION (#2)
If one of your customers notice that his Parsun 5 hp motor (model prior to 2009) stops working after a few minutes,
check this valve. It could be the p/n PAPF4-05000100 problem.

66629 some (bad :o) copies of the pics from the PDF's
click pic to enlarge

Good luck !
Angel

Angélique

01-30-2012, 11:59 PM

my bad, thought he had a two stroke :o

Hey, you gave great tips about two strokes, maybe some day someone in need finds them and will be grateful for it, so please don't erase them :)

Watson & LP gave great tips as well http://www.boatdesign.net/forums/images/icons/icon14.gif, I'll try to remember those too . . :idea:

Cheers,
Angel

Manie B

01-31-2012, 02:21 AM

Thanks folks for all the info, much appreciated.

My local agent = Motor King and Marine (Leon) is really fantastic, absolutely no problem AND no charge, even if I bought the motor more than a year ago. They definately have plenty of spares.

It seems to be primarily 99% a fuel problem with these motors. They stripped and cleaned the carburettor while I was looking on and gave me some info and "training"
Time will tell but these 5hp fourstroke engines should be ok, they are in fact very simple little motors, easy to service. A good inline fuel filter is a must.

I would suggest to anybody that takes a new motor out for the first time, leave the boat on the trailer and run the motor "in gear" for 30 minutes. Play safe, it's the right thing to do. In any new installation there can be that hidden bit of dirt just waiting for you, it's Murphy's Law. Once the system has flushed it self your chances are so much better for success.

Angélique

01-31-2012, 02:30 AM

.... A good inline fuel filter is a must ....

When installing it, best remove the standard fuel filter on the tank bottom which can get lose and block the fuel tube, see post#530 (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-36.html#post524796).

Good luck !
Angel

hoytedow

01-31-2012, 06:26 AM

Found this by KenTheCanadian on

Yachting and Boating World Forums > Practical Boat Owner's Reader to Reader > Link (http://www.ybw.com/forums/showthread.php?t=279091)

http://www.boatdesign.net/forums/images/attach/pdf.gif PDF format version of the 201 Parsun flyer. (http://www.mticanada.ca/pdf/ParsunDepliantEN110419.pdf)

http://www.boatdesign.net/forums/images/attach/pdf.gif PDF service bulletin about filter on 5 hp motors. (http://www.mticanada.ca/pdf/ParsunBulletinPA01_2100212.pdf)

* - I'll guess this must be . . . ‘‘push the filter inside the tank’’ . . . but not sure as I haven't seen it for real.

- - And secure the filter wherever it belongs . . :idea:

http://www.boatdesign.net/forums/images/attach/pdf.gif PDF service bulletin about 5 hp motors gas valve seal (models prior to 2009). (http://www.mticanada.ca/pdf/ParsunBulletinPA02_100212.pdf)

66629 some (bad :o) copies of the pics from the PDF's
click pic to enlarge

Good luck !
AngelI thought I might re-do that one photo.http://www.boatdesign.net/forums/attachment.php?attachmentid=66640&d=1328012677

colfar2

02-01-2012, 12:17 AM

Fantastic Job Manie always knew you would get her in the water and motor setback was just there to test you :P

Manie B

02-09-2012, 06:08 AM

This past weekend I came right and the fuel problem is sorted.
The intial problem of dirt in the carb was cleaned and then I had a fuel starvation problem that was solved by re-installing the "bulb" rubber hand pump in a more "upright" position closer to the motor, this really worked well and I will do more test this weekend at Hartbeespoort Dam.

Gents I need help.
I really like a "balanced lug" rig
when you look at these videos of "Scamp" it clearly shows that reefing can be done easily from the cockpit and it all happens along the boom.

scamp sailing
http://www.youtube.com/watch?v=I0C6Mr1HmPc&feature=related
this video shows the reefing setup

scamp capsize test
http://www.youtube.com/watch?v=du9lvJNVqnk&feature=related

scamp thread
http://forum.woodenboat.com/showthread.php?139540-SCAMP-envy-lust

when you consider that Roger Tailor has covered vast distances up north with a junk rig - the balanced lug is not that "different"
http://www.thesimplesailor.com/voyages.html

I have watched these videos over and over again, studied the pics in finest detail, and the more I like it.
Problems is that I have never seen such a rig in my country, the "regulars" dont really know what I am talking about ( they actually know very little after all ) and this could very well be a first for this country, I just dont know.

What do you folks think of this rig as a "long distance" open water cruising rig
Its simplicity is easy to see, far less things to go wrong for a 16 ft boat.

Manie B

02-09-2012, 06:17 AM

oh and keep in mind the Corribee (Roger Taylor) has virtually the same LWL as my micro at 16'6"

michael pierzga

02-09-2012, 06:32 AM

Perhaps research Nigel Irens designs , he uses a modern lugg

Roxanne...

http://www.nigelirens.com/nid_CRUISING3.htm

http://www.romilly.nl/

http://www.jachtbouwbartjanbats.nl/uk/BJ17_1/

http://www.roxane-romilly.co.uk/Romilly/

troy2000

02-09-2012, 10:59 AM

I don't remember Phil Bolger's exact wording. But in one of his books, he said the balanced lug rig is so well suited to motor sailors that it's a testament to [something-or-other uncomplimentary] that it isn't used more often.

I think your little mini probably qualifies as a motor sailor....

Angélique

02-09-2012, 12:31 PM

I really like a "balanced lug" rig . . . . . . . this could very well be a first for this country, I just dont know.

Maybe CKD Boats (http://www.ckdboats.com/) in Cape Town has build one yet (http://ckdboats.blogspot.com/2011/10/balanced-lug-rig-for-pdf-racer.html) . . . . ? ?

Good luck !
Angel

Manie B

02-09-2012, 12:33 PM

Well I have now read most of the Roxane - Romilly pages and I must say the info is just fantastic. Nigel Irens obviously has done well with the balanced lug and the owners love it.

I must add that the S.C.A.M.P. (Small Craft Advisor Magazine Project) design by John Welsford is excellent. When you study the videos carefully you can see that the setup for reefing has a lot of experience and expertise behind it.

I was worried that my proposed 17 sq m sail is big - but it is nothing compared to what Roxane carries at 4 times that. Bottom line for me is that folks with a mountain of experience are enjoying the balanced lug under many different weather conditions.

Please keep the comments coming for this sail arrangement, you can understand that I am scared.

I am now working on my electrical installation, solar panels, DB panel, instrumentation and lights and what not else. The electrical is a lot of work. I can now sleep anchored out, so that I get the real feel for the interior.
I as a "shorty" can move around very easily, but visitors may find the interior "confined" or shall we just cut to the chase and call it "tiny" :P
Anway the confidence is growing with the towing, because on our "roads" with the "locals" driving, it is a nerve racking "mission impossible"

So far so good, the boat is exactly as planned and everything has worked out just the way it was envisioned. I am a 100% happy and thank my lucky stars that the boat is not even 1" bigger, if anything 6" smaller would also have been OK. Finally I am back on the water which is really what it is all about, now I can play with my "toy" until doomsday.

So if nothing really bad comes out of the woodwork against the balanced lug, I could probably start on that in about 2 months time.

Thanks guys.
Your input is important.

masalai

02-09-2012, 07:44 PM

Thanks Manie, Good to hear your progress...

Now for something to please/annoy ? http://gprime.net/video.php/bassbumpers

Manie B

02-09-2012, 11:43 PM

CKD doesn't seem to have gotten far either, it seems like the "kit" market is dead. :eek: boating is not beeeg in a 3rd world :eek:
the locals are "hunter gatherers" ;)

troy2000

02-10-2012, 02:54 AM

CKD doesn't seem to have gotten far either, it seems like the "kit" market is dead. :eek: boating is not beeeg in a 3rd world :eek:
the locals are "hunter gatherers" ;)

From what I've seen on the internet, the '3d world' nowadays builds its sails from poly tarps and duct tape and gets on with life. You could probably do worse than emulate them, at least until you've tried out your ideas. After you come up with a poly tarp sail that seems to work for you, take it to a professional sail maker. He can use your results to sew you a real one, that will probably work even better.

michael pierzga

02-10-2012, 03:32 AM

An Important part of your sailplan will be a cockpit awning.

Could be worthwhile to put your thinking cap on . The awning is what makes a small boat livable.

The Boomless Irens lug looks great because it will give plenty of headroom , but it also clutters with a stack of sail and battens on deck .

Manie B

02-10-2012, 05:57 AM

The poly tarp sail is definately the way to start
the pain is cutting a hole in the deck and "installing" the mast etc. that is where the worry part kicks in (what if and and)

the idea is a lug with the boom, that is what started my interest. All reefing is along the boom and the lines from the tack can be led back to the aft end of the boom. This means that I could reef from the safety of standing in the hatch, all lines back to the cockpit.

it is clearly visible at around 27 sec in this video
on the port side of the boom

http://www.youtube.com/watch?v=GomIAiuqfws

simple but brilliant
you can even install lazyjacks, I saw a video of it and its great

hoytedow

02-10-2012, 07:25 AM

From what I've seen on the internet, the '3d world' nowadays builds its sails from poly tarps and duct tape and gets on with life. You could probably do worse than emulate them, at least until you've tried out your ideas. After you come up with a poly tarp sail that seems to work for you, take it to a professional sail maker. He can use your results to sew you a real one, that will probably work even better.A polytarp will get you "out there" but will it get you home?

michael pierzga

02-10-2012, 07:36 AM

As for sails...we throw them away.
Im trashing a mainsail right now. Always check with a sailmaker for old sails. The body of the sail Im replacing is in perfect shape...only the edges...luff, leech and head are beyound repair. Plenty of good shape left in the body.

Angélique

02-10-2012, 12:45 PM

http://www.boatdesign.net/forums/attachments/boat-building/66608d1327917237t-manies-microcruiser-893.jpg (http://www.boatdesign.net/forums/attachments/boat-building/66608d1327917237-manies-microcruiser-893.jpg) 67082 http://www.boatdesign.net/forums/attachments/boat-design/65699d1325824311t-8-puddle-duck-12-puddle-goose-10-eider-duck-_ooze_goose_.jpg (http://www.boatdesign.net/forums/attachments/boat-design/65699d1325824311-8-puddle-duck-12-puddle-goose-10-eider-duck-_ooze_goose_.jpg)
click pics to enlarge

I see (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-34.html#post524431) you already have an awning, not sure that's the definitive one, if not then Ooze Goose (http://www.duckworksbbs.com/plans/korhonen/oozegoose/index.htm)'s boomtent might be of some inspiration . . . . here the plans (http://www.duckworksbbs.com/plans/korhonen/oozegoose/Boomtent-OozeGooze.pdf).

Maybe a Lug Yawl rig like the Ooze Goose and the Nigel Irens designs is also an idea, great trim opportunities and ease at anchor.

Here Michael Storer about balance lugs (http://www.storerboatplans.com/Faq/tradrigperformance.html) in different versions - but you might have seen already ?

Good luck !
Angel

Manie B

02-10-2012, 04:17 PM

:)

the "awning" is a temporary shelter
cant go out in the sun
the real deal will come later when the rig is up

:D

cookiesa

02-10-2012, 04:42 PM

Have been contemplating awnngs myself, problem is most are based around boom tents and sitting at anchor, I'm working on something that sits under the boom and allows for use whilst sailing.

The cheaper commercial ones don't seem to be quite the right dimensions so have been pondering somethiong similar to the Ooze Goose one but using fiberglass tent poles to hold the shape slipped in to pockets on the awning, easy to pack away and store when not im use, just have to fins some that don't have steel joiners :)

Doug Lord

02-10-2012, 05:09 PM

masalai

02-10-2012, 08:40 PM

Good idea Doug...

cookiesa,
I posted links to the supplier of my stanchions and rudder posts and tubes (done nicely in grp) Angler Fishing Rods, 15 Ada Street, Coopers Plains QLD 4108, Australia 61 7 3274 1099 - - <coordinates>153.033773,-27.564639,0</coordinates> tell them what you want and how much flex (12 ft length to be able to be spring bent to form a semicircle inside "x" ft diameter and have integral joining sleeves in Grp or whatever....) and cheaper than a one off, ask what they have that may suit?

Manie B

02-11-2012, 12:54 AM

Well folks there is a mountain of info available on lug sails
I am posting bits as I go along because I really think this could help a lot of guys that are working to a tight budget

I also fully agree with Bolger and other designers who observe if sailmakers put the research into lugsails that they put into high tech Bermudan mains and jibs, the sail would perform much better. In fact, I suspect there would be no reason, except for the racing fanatics who want the nth degree of windward speed and pointing ability, to use the high-stress and expensive sloop rig. The lug would be better for 99 percent of the sailing we do.

Also surprising is on a couple of occasions while working on tacking I was able to get the boat to tack on 80 degrees. It went slowly so pinched, but I’m amazed it could point that close at all. The speed was much better on those days with 90-100 degree tacks.

The mast on the 30-footer is about 28 feet above the waterline

full article here
http://www.duckworksmagazine.com/06/howto/lugsails/index.htm

rwatson

02-11-2012, 04:45 PM

Surely you should get a professional assessment of your mast location, sail area and righting moment based on your hull design. A little bit of calculation will save you weeks of frustration and bad decisions.

There are several competent people in this forum that could do the job for a very reasonable fee - (hands up anyone who is able to help.)

It would be shame to put in so many hours and screw up the final stage.

Manie B

02-12-2012, 03:21 AM

I am surrounded by some seriously qualified degreed and educated folks around me, so calculations are no problem as we check these things from a couple of different angles. Wynand's history is well known but the day Dries publishes pics of the mega yachts that he built in Cape Town your jaw is going to drop. Fanie has got engineers coming out of his ears :) that also do some serious stuff of all manor and nature.

As this is an "experimental" craft, with me as the builder (read old fart) there are always more questions than anwers, and I think that is the allure or the "magic" of such a vessel / project. So the one thing that has been a HUGE SUCCESS - is it - FLOATS :D:D

So we are off to a good start ;)
the "bucket" works and the porta potty is still in its box :p

Back to the future
I really like a balanced lug
I have read and read and read some more
now I love it

BUT is it the right thing to do ?
that my mates cant answer for me, I have to take the plunge and sink or swim with the budget and the consequenses.

The irony is that I cannot find ANY reference to such a rig in deepest darkest southern tip of Africa
the regulars at the yot klab pub get that glazed look in their eyes
so are they pissed
or dont they know
you will never know :eek:

Bottom line is the project has increased it "fun" index by 300 %

so here are some preliminary "number"s
they will change dont worry :eek:

Lead 10%
as per Larsson and Eliasson page 172
Ted bruwer page 56/57
your guess is as good as mine;)

RM approx 350 kg/m
POYD p 44/215
Dudley Dix history pages???

Empty boat 450 kg
with centerboard and bulbkeel total 600 kg
with other junk up to 700 kg total
the bulb at 160 kg is 1.7 m below water at 2.3 m from stern CLR
she is a solid heavy little beast 700 kg is no light weight

5.05 m on deck LOA
LWL 4.85 Beam 2.3 m

sail area 16.5 sqm
6m mast - 770 deep into its socket
CE approx 2990 above deck and 1010 behind the mast
so a fat thin wall mast
or a thick wall - smaller dia mast
wood? aluminium? carbon fibre?

and never forget
until somebody comes up with different info
a first for south africa
jeez I am an adventurous guy
but I have never bungee jumped and never will
and still it feels like jumping of a cliff
:D :D :D

must be the age catching up :P

Manie B

02-12-2012, 03:25 AM

Oh and I must add
yard 40% forward of mast
boom 15% forward of mast
luff paralel to mast

as per the experts

Andy

02-12-2012, 05:39 AM

Looking good Manie. Don't know if you've seen these:

http://www.polysail.com/lug.htm
http://www.simplicityboats.com/simplicitysailrig.html
http://www.jimsboats.com/15sep11.htm

Obviously at the cheaper end of the scale, but with reinforced heavier (white) polytarp, a soldering iron with the tip hammered flat for hot-knifing, and not much time or cash you can experiment away to your hearts delight.

Andy

02-12-2012, 05:42 AM

Ps for the mast I've been wondering about hollow birdsmouth douglas fir spars with thin walls, carbon fibre uni wrapped around the mast on the 90 degree axis to give 'hoop' strength and hopefully prevent buckling...again, I'm sure you can play around with your tiny stick, as it were!

Wynand N

02-12-2012, 08:21 AM

Wynand's history is well known but the day Dries publishes pics of the mega yachts that he built in Cape Town your jaw is going to drop.

and there goes your boat's certification papers....:rolleyes:

Manie B

02-12-2012, 08:33 AM

Hi Andy thanks for posting, I have seen those sites, they are all good.

The general consensus seems to be to go for a 100 dia x 3 mm wall aluminium pipe. (4" x 1/8")
The advantage of this is the strength for a freestanding mast
and the huge amount of positive floatation that comes as a bonus with it sealed or filled with PU foam

The downside is big windage of a stick that towers 6m (19'8" = 4' boat and 15'8" mast) above the water, the boat already has a big windage factor for a small boat.

Aluminium pipe is strong, cheap and can be anodised or powder coated,
our local woods are poor quality and imported stuff is crazy expensive
so an "ally" mast is cheap and easy

so once again I am faced with something that is not tangible
what does a 6m x 100dia mast look like on a 5m boat
I have nothing to relate it to
I cant take a walk to the harbour to go and look around at similar rigs
the harbour is 700 km away and I will bet you a bottle of Whisky that you wont find ANYTHING even remotely close to what we are talking about in Saffa

so back to YouTube
and the input from the forum from guys that live and grew up next to the sea and have "seen" things with their own eyes :cool:

Manie B

02-12-2012, 08:40 AM

Wynand thanks a million for the certificates, all good, thanks.

Ok guys now I am off to go and work on Masalai's coconut oil farm :D

got COF and Bouyancy and skippers and passport
papers are ready

OOOOPss

where did the mast go

hey who the hell forgot the sails :P

damn still no crew :P

Manie B

02-12-2012, 08:58 AM

I have updated the CAD drawing
to show a stick 4" dia 20' above the water

doesn't look too bad
just dunno

it's Sunday afternoon here
time for a beer and barbeque
tired of worrying about an ally pole

:P got a good idea :P
show my big stick to some "crew"
:D still love wicked weasel :D

troy2000

02-12-2012, 09:06 AM

Wynand N

02-12-2012, 09:25 AM

Wynand thanks a million for the certificates, all good, thanks.

You're welcome, anything for a friend:cool:

Manie, let me have the righting moment of your boat @ 30 degrees heeled, mast height you looking at and chain plate width (across deck) and I will calculate spar moments of inertias for you if you go the ally way;

1. free standing
2. Stayed with one spreader pair (keel stepped).

OTOH, I would go for a hollow wooden mast and will do some calculations and basic drawing on how to build and let you have the lot and then you can decide which material and type to use.

Wynand N

02-12-2012, 09:35 AM

Fanie has got engineers coming out of his ears :) that also do some serious stuff of all manor and manure.....

:eek::confused: care to explain?

Manie B

02-12-2012, 01:08 PM

Wynand the idea is a free standing mast
my math is hopelessly outdated to calculate RM, so I am guestimating;)
mast heights are on the drawing
and all other dim in previous post :confused:

rwatson

02-12-2012, 01:49 PM

sigh - the spirit of "lets stay confused because its exciting" reigns in SA.

Its fun to make decisions based on "I read it somewhere" , but to my mind, the height of the mast and the sail area come well after someone smarter than me knows how much wind it will take to blow your "bliss box" on its arse. For someone so careful to make a seaworthy boat, it seems the mast/sail design business is a wee bit .... "hit and miss"

Now, does the lead weight and keel length get calculated before, or in conjunction with, the mast/sail calculations ? So many decisions ...

Aww .. bugger it, rip a rig off an old 20ft yacht, hang a bag of bricks under the hull, and see if it works ! :)

Manie B

02-12-2012, 02:12 PM

no its not that bad ;)
we got a lot of info

still just thinking out loud ;)
she will come upright ;)

floats high and dry on its side

one guys tender is another guys responsive
your guess is as good as mine

masalai

02-12-2012, 02:38 PM

Hi Manie,
Do you still need to see what a 6m length of 100mm mast "looks like" - how about some plastic down-pipe or drain-pipe from your friendly plumber supply/hardware store? - - it may be grey or off white but here a popular size is 100mm...

Best wishes and C U soon...

Manie B

02-12-2012, 11:07 PM

Mas I may very well do that

Just to the guys in general
your input is always appreciated

the question here is not so much HOW
plenty PhD's around here
and tons of technical data to number crunch thru a vast network of computers
(that lack real world experience)

the real question is WHY
that is why I turn to the BD.net
to get input from guys that are "close" to the real world where balanced lugs are actually seen and used
the practical world with years of experience that understand "hands on"

masalai

02-13-2012, 01:43 AM

Aye lad, it always pays to get outside opinions, good or bad .... I appreciate them all, - even though I all-too-often do not feel that I declare so... :o

My response, sadly, - (since I am a mere human) - should often-times be more appreciative, - - - but if 'things' locally give me the s41ts, then I will likely be in a s41tty mood.... Ahhhh the ways of humanity... (An admonishment to myself, as, at the moment I am quite mellow........ ) and preparing to 'pig-out-on-a "road-kill"' of roast mutton (too big to be lamb) :D :D :D :D

Wynand N

02-13-2012, 05:13 AM

and preparing to 'pig-out-on-a "road-kill"' of roast mutton (too big to be lamb) :D :D :D :D

Sure its mutton and not kangaroo :confused::D

masalai

02-13-2012, 05:38 AM

Sure its mutton and not kangaroo :confused::D

Well the kiwi was kissing it and removing its woollen coat :confused: :?: and I am pretty sure it was a weather;) - but I only removed the right rear leg as it was uppermost and cleanest (the kiwi had skinned that part first...taking the hock):D:P

02-16-2012, 06:29 AM

In profile your cruiser bears a bit of resemblance to this. The scale is much different though.

67290

It got me thinking though and here are a couple of videos you might like to see regarding furling the rig of this cruiser and also Enigma. They are very interesting to see though the scale would most likely not work on your rig without considerable "beefing" up.

http://www.youtube.com/watch?v=2DVAnCQJqLI

http://www.youtube.com/watch?v=1NaNtUEMYgw

They were pulled from this site.

http://www.microcruising.com/

Very inspirational for cruising small.....maybe to an extrreme.

Manie B

02-16-2012, 08:15 AM

Hi LP
yes I am very up to date about Enigma
definately some good ideas

we are doing the "math" now, the guys are just waiting for me to supply the new CAD drawings
once that is done over the next couple of weeks I will post the "finer" details

so far I am almost 100% sure that we are in agreement that this is the way we will go - 99% similar to S.CA.M.P.
freestanding stick - balanced lug - reefing as per Scamp
all reefing done on the port side of the boom at 27 sec into the video EXCELLENT
http://www.youtube.com/watch?v=GomIAiuqfws&context=C318c336ADOEgsToPDskJ8Eyjr7BwcZkDXkWx8EV5b

Angélique

02-16-2012, 12:33 PM

so far I am almost 100% sure that we are in agreement that this is the way we will go - 99% similar to S.C.A.M.P.

SCAMP is not a long distance cruiser, yours is, how will you make the boat self steer, electric or windvane or . . . . ? ?

Tread Lightly (http://www.jwboatdesigns.co.nz/plans/treadlightly/index.htm), SCAMP's somewhat bigger sister . . . . .

67295
click to enlarge

More pics at DW (http://www.duckworksbbs.com/plans/jw/treadlightly/index.htm).

Good luck !
Angel

Manie B

02-17-2012, 04:06 AM

Steering is sorted ;) "oneday"

the first is a twin rudder system similar to the pic

secondly is a Raymarine ST 1000 tiller pilot

and most importantly the windvane
I was writing to Rory McDougal when he was doing the Jester
he has been very helpfull and also helped me to get the book
Wind-Vane Self-Steering by Bill Belcher (out of print)
my copy is in excellent condition and an asset to my library

The windvane on "Cookie" has proved itself over and over
and is most definately what I will eventually do
easy to build and service and maintain
and easy to modify to suit "Fargo"

:D I have to start using the name "Fargo" because Wynand has sorted my Bouyancy Cert as well as my C.O.F. so the name is now in black and white on paper :D
so the boat is legal :cool: thanks to Wynand :)

read all about Rory and Jester
http://roryandcookie.blogspot.com/

read all about the magic of a lap in Cookie
http://roryandcookie.com/

I was very fortunate to have these pics before they went public
cool bananas :D

please dont ask the question
will this boat EVER get finished ??

dunno :eek:

Manie B

02-17-2012, 04:08 AM

ooopps

the pics

Manie B

02-27-2012, 12:27 PM

:)

Isn't it beautifull

a balanced lug sail is just soooo cooool

:)

Fanie

02-27-2012, 12:32 PM

Doesn't count Manie, show it to me in wind !

Manie B

02-27-2012, 01:18 PM

:)

i have a couple

how about this one that shows it reefed

http://www.youtube.com/watch?v=IVSo1E8tTbw&feature=related

good one for a very light boat
look at the wind surfers in the background

Manie B

02-27-2012, 01:27 PM

Take note of how well it gybe's in this video

http://www.youtube.com/watch?v=QE25DQ410lQ&feature=related

Manie B

02-27-2012, 01:35 PM

These boats are amazing
look at how light the helm is

http://www.youtube.com/watch?v=WN_V3KGprdU&feature=related

think about this
1 - freestanding mast
2 - easy to reef
3 - economical to build
4 - easy to maintain and service
5 - very easy to scandalize the main
6 - 3000 years of proven usage
7 - add modern materials and its rather good!

Fanie

02-27-2012, 01:50 PM

My modem works at 2 - 4kbps for the last few weeks. Hell the service in this cuntry is fu... I mean pathetic ! I can't watch the movies, the 35 second one is going to take two hours to play :( It's been pathetic since vodacom took the service over. Every thing with 'com' in it in SA is crap. 4 5 C. Now it has slowed so I can hardly receive e-mails and it even seizes in between. I'm sure they 'save' on bandwidth somewhere or some 'eh eh eh no but' is in charge of something he has no clue about.

Manie B

02-29-2012, 01:04 PM

Well folks

I am eternally grateful for all the hard work Wynand has put into this project
he has spent countless man hours slogging away

today he gave me the biggest birthday present a man could wish for
PEACE OF MIND

the boat is definately safe
VCG 1.704 m from the bottom of the bulb keel
LCG 2.812 m from station 0 bow
GZ 0.810 m @ 30 deg heel (meta centre)

resulting in an astonishing stability curve
that is definately kinda cool

"drum roll please"

:D

Manie B

02-29-2012, 01:12 PM

Oh and I must add this is full of food, booze, fuel and 2 old farts at a total of around 1000 kg
not to shabby

masalai

02-29-2012, 03:05 PM

Well done Manie, Congratulations on an excellent boat - Now go sailing !!!! :D :D :D

rwatson

02-29-2012, 03:06 PM

Well folks
..... the boat is definately safe
VCG 1.704 m from the bottom of the bulb keel
LCG 2.812 m from station 0 bow
GZ 0.810 m @ 30 deg heel (meta centre)

resulting in an astonishing stability curve

I can't believe you didn't do this at the beginning of the build. Are you some kind if thrill seeker designer :)

Now, who did the engineering calculations on your scantlings :?:, or are you going to see if the keel will break during the first big blow ?

Wynand N

02-29-2012, 11:18 PM

Manie, just a word of caution...

When I done the weight calculations to peg the LCG, I used all the data for the hull from the FreeShip file you supplied and all the other relevant weights like bulb keel, interior, batteries etc etc right down to the whiskey onboard.
The stability curve is for the boat loaded to waterline - displacement 945kg - which place the LCG at the numbers you posted. Just for interest; the highish and boxy doghouse had a direct result on stability from 60 degrees of heel upwards hence the high angle of vanishing stability at 136 degrees. The boat also has an excellent positive to negative and vice versa ratio of 5:1. (times the smaller inverse stability curve max number will divide into the bigger positive stability curve max number)

However, you are running light ship at the moment without keel for instance - 160kg bulb at 1.60 meter below LWL - which takes a lot of righting moment away from boat and raises the LCG considerably that directly influence positive stability.
Currently you you have only form stability that is ample looking at the curve say up to 10 degrees of heel and a direct result of the high beam to length ratio and relative flat bottom. If you accidentally heel the boat now to about 70 - 90 degrees it would be game over :!: But I do not see this happening when motoring around on the fishing ponds.

I can't believe you didn't do this at the beginning of the build. Are you some kind if thrill seeker designer

Now, who did the engineering calculations on your scantlings , or are you going to see if the keel will break during the first big blow ?

rwatson, why the negative waves :?: At least Manie had the balls to design something he wanted, went out and built it and is now enjoying the fruits of his labour. Granted, it is not finished yet, but to fit the keel is piece of piss and to calculate the scantling to support the keel will only take an hour or so and Manie can easily do the necessary reinforcing if called for.
That said, I'd seen the boat under construction and it is indeed well built.

BTW, did you by any chance attempted what Manie did?

troy2000

02-29-2012, 11:33 PM

Manie, just a word of caution...

When I done the weight calculations to peg the LCG, I used all the data for the hull from the FreeShip file you supplied and all the other relevant weights like bulb keel, interior, batteries etc etc right down to the whiskey onboard.
The stability curve is for the boat loaded to waterline - displacement 945kg - which place the LCG at the numbers you posted.

However, you are running light ship at the moment without keel for instance - 160kg bulb at 1.60 meter below LWL - which takes a lot of righting moment away from boat and raises the LCG considerably that directly influence positive stability.
Currently you you have only form stability that is ample looking at the curve say up to 10 degrees of heel and a direct result of the high beam to length ratio and relative flat bottom. If you accidentally heel the boat now to about 70 - 90 degrees it would be game over :!: But I do not see this happening when motoring around on the fishing ponds.

rwatson, why the negative waves :?: At least Manie had the balls to design something he wanted, went out and built it and is now enjoying the fruits of his labour. Granted, it is not finished yet, but to fit the keel is piece of piss and to calculate the scantling to support the keel will only take an hour or so and Manie can easily do the necessary reinforcing if called for.
That said, I'd seen the boat under construction and it is indeed well built.

BTW, did you by any chance attempted what Manie did?

A big 10-4 on that one. It's easy to sit in the shadows and potshot those who are actually doing something....

Judging by the thread as a whole, it's obvious Manie didn't just pull a plan out of his * and start building it, with no idea whether it would work or not.

Manie B

03-01-2012, 12:21 AM

Guys I should have explained a bit more as I posted last night, but the exitement levels were a bit high

When I started the design some 3 years ago I consulted with Wynand on a regular basis, I even slept over at his house a couple of times and we had loooooong discussions around the "barbeque" late into the night. So a huge amount of design criteria and scantlings were in place LONG before any wood was cut.

What happened during the build is that the "owner" made design changes to the interior and added extras. :)

The nightmare of any builder is the owner that wants this that and the next, so no difference here :)

So I had a very comprehensive plan in hand with pages of notes before I started. Then came the "modifications" - bunks - galley - chart table - internal forward storage area - external forward storage bunker for fuel, the list goes on.
So as the interior grew, the weight got more, and so did the anxiety. That is why I was so desperate to get the boat onto the trailer so that I could get it to the weighbridge. The boat is probably around a 100 kgs over weight. There are places that is silly strong over the top, but it was easy to do at the time.

Now you can understand the relief of these caculations that are done on the actual boat with the actual weighbridge weigh.
During a build like this as a "one off" there are many things that can go wrong - and thank gawd it did not

So I can honestly say that we did what we were supposed to do.
At this stage of any new build to any design, you start panicking,
Waaaaay over budget (like Double)
Waaaaay over the time estimate (like Tripple)

never mind the tight fit into the garage, if the trailer manufacturer misread the drawing and built the trailer 50mm (2") higher the boat would not come out of the garage !

so lots of sleepness nights
and thank the heavens that everything is working out perfectly so far

:P and so we are of to the next MAYOR change - a freestanding mast with a balanced lug sail :P

jeeez I owe Wynand beeeeg time

oh and before I forget
a big thanks to Dries that came and popped in regularly to check my work
I should not say this publicly but Dries is the engineer in charge of building unmanned aircraft out of carbon fibre. Dries also ran a big sailboat factory in Cape Town in his younger days.
http://www.epsilon-eng.com/
that is where I sat in a composite plane the size of a 4 seater cessna

so no wild chances were taken
everthing becomes calculated risk
building a boat is part science, part art and part collective wisdom
hope this explains a bit more

oh thank goodness it floats :eek: :eek: :eek:

Manie B

03-01-2012, 12:39 AM

Oh and I must add a big thanks to all the BD.net guys
ALL OF YOU
over the years many questions were answered on this forum
often critisizm good or bad led to "deeper thought" and things were reconsidered or confirmed, it all went down well.
and the PM's were always helpful

If one had to draw a fully comprehensive set of drawings for a small boat like this, the drawings would cost more that the boat.

Wynand N

03-01-2012, 01:33 AM

:P and so we are of to the next MAYOR change - a freestanding mast with a balanced lug sail :P

Now that we have righting moment numbers Manie, I will get onto the cantilever (oops, I meant mast) inertia calculations as soon as I have a bit of spare time and see what ally stick will do duty on Fargo. :cool:

Manie B

03-01-2012, 02:37 AM

Ah - and now a word to Colin

:D hey Colin, its confirmed, 160 kg is correct !! :D

just so that you guys know who Colin is
http://www.boatdesign.net/forums/boat-building/my-russian-boat-29783.html

Colin works at a steelworks that manufactures re-bar for construction and has organized steel offcuts for me at scrap cost
this will be moulded into the bulb with epoxy

waay waay waay frikk&n cheaper than anything else

Manie B

03-01-2012, 02:41 AM

:D

a bulb keel

:eek:

anxiety

rwatson

03-01-2012, 04:00 AM

rwatson, why the negative waves :?:

"Whats with the Negative waves - Moriarity ?? ;)

Xyh-JpWdGmQ&feature=related

At least Manie had the balls to design something he wanted, went out and built it and is now enjoying the fruits of his labour. Granted, it is not finished yet, but to fit the keel is piece of piss and to calculate the scantling to support the keel will only take an hour or so and Manie can easily do the necessary reinforcing if called for.
That said, I'd seen the boat under construction and it is indeed well built.

Having the 'balls' is not in question, but sailplans, scantlings, and righting moments usually get sorted out before anything is started.

As Manie points out subsequently, he opts not to do the full design to save money, but I personally wouldn't go offshore in a 'Development' model. I know he is planning small trial stages- but who needs the aggro - really!.

Likewise "Manie can easily do the necessary reinforcing" ? That's my point I guess - considering that the keel holds the whole thing up, not having the details sorted till after the build, is ass about, even in S.A. I cant imagine the work involved in ripping into the boats guts in the event that the calcs dont come up right.

Hell - three 'newbie' boatbuilders a week get 'smacked about' in these very forums for not choosing a proven design for all these very reasons, so Manie wont mind me digging him in the ribs - hopefully. ( smile Manie :) )

BTW, did you by any chance attempted what Manie did?

Yeah, many times - the latest gets a mention at
http://www.boatdesign.net/forums/projects-proposals/historic-home-made-tri-41690.html

... which is the reason that my current project is getting the full design completed before a single plank is cut.

Wynand N

03-01-2012, 04:44 AM

As Manie points out subsequently, he opts not to do the full design to save money, but I personally wouldn't go offshore in a 'Development' model. I know he is planning small trial stages- but who needs the aggro - really!.

Likewise "Manie can easily do the necessary reinforcing" ? That's my point I guess - considering that the keel holds the whole thing up, not having the details sorted till after the build, is ass about, even in S.A. I cant imagine the work involved in ripping into the boats guts in the event that the calcs dont come up right.

Watson, perhaps I am an oddball myself - see attached picture of yours truly in my "Lotus 7" attire taken some time ago...:D

For starters, read Manie's post that we did spent long hours discussing/planning the boat and did the basics before even a plank was cut. Because this boat is a close copy (Manie's version) of a well known boat, we knew all along the stability should be OK.
Construction was well thought out and is clear from the pictures he posted today. At the outset he was not sure what keel to use hence the detail not worked out at the stage and as the great man said, things has a tendency to change as one progresses...
Now that we know its a retractable bulb on fin, I will look over the keelbox and installation thereof when in Manie's backyard again, run some numbers and see if it needs to be reinforced. That said, you will notice that the floors are not installed yet and a simple matter to do supporting with a bit of ply and epoxy should it calls for.

BTW, did you noticed that Manie painted the boat before building it;), we do it all the time in SA painting homes before we build them:D:D

Funny you posted the link to your past built because...or, rather let me quote ;)

Having the 'balls' is not in question, but sailplans, scantlings, and righting moments usually get sorted out before anything is started.

[I had no plans, just a few pictures of a Wharram Catamaran

[It was a lot of trial and error until it worked properly.

At least Manie did not have trail & error issues - we speculate, then calculate and finally pray before doing it...

EDIT: Sorry I touched a religious cord Jeff

Manie B

03-01-2012, 05:57 AM

Wynand i love the pic :D :D :D

ok now I was busy writng this response and then the power went off
btw that happens often now in the "rainbow nartion"
anyway I saved it and here goes

As Manie points out subsequently, he opts not to do the full design to save money

Let’s just clarify that point

I did actually start off with a full complete design
Just not a detailed complete set of drawings that is millimetre accurate

What the problem is, and anybody that can CAD will verify, you can draw until the cows come home, you never get the sizes and dimensions "nice"

That last 20mm either this way or that way is what takes a living space from good to great. How often doesn't it happen that you say to yourself, jeez if this or that was just that half an inch away it would have been a lot better
Now you will understand how I got everything to fit "perfectly" Even when you look at the motor it is hard to imagine that it swings completely up and out of the water, my 10 litre water bottles under the bunks go in and out in comfort, and many more.

So what I actually achieved here is what a production boat gets to - by the "new superseded "model #3 or #4, how often haven’t you been on a Beneteau and realised that furniture was "pushed" and "forced" into position because something was "slightly" out of place

I can draw this boat to 0,001 mm accuracy on my CAD and believe me that won’t help a bit. Keep in mind that I did an apprenticeship as a Mechanical Design Draughtsman and in those days we still worked with slide rules, and that is how I did exams for my engineering diploma. I pushed a pencil on a drawing board for years.

The point is, a boat like this is an “organic” living thing
It grows and matures under the hands of the builder
As you go along, you can’t stray too far off from the design and basic drawings
You have to “feel” it, move everything a little this way and then a little that way, often ending up in the same place that is was originally.

So the complete “design” was there from day one
Now you go and “paint” the picture – and that when the fun starts
No two planks are the same size, no two sheets weigh the same,
In winter the same epoxy differs like day and night from summer
The list is endless

And that is the charm of boatbuilding,
Everything changes constantly, that is what is so intriguing, and makes us come back again and again for the same punishment.
Proto types are always fun. I got mine right to a 100% where I wanted it now. But it came at a price, double the cost and triple the time. Some folks would have built the first one, scrapped it and got it “right” with a second or a third. I mean really, how often don’t we read about that here on BD.net. I opted for the first, and that is what happened, I took my time and re-did things there and then. The boat is strong, as you have gathered by now many friends had a helping hand in this, I just did the work.

There is plenty carbon fibre and Aramid (Kevlar) reinforcing, all installed after “consultation”
I built the boat - but it is a collective effort of many guys

So bottom line is – how do you know if a boat floats – put it in the water!
Go onto YouTube and you will see some really funny movies of professional launches that went horribly wrong.

Oh well its all fun anyway.

Manie B

03-01-2012, 06:09 AM

Now that the "lights" are on again lets try this :)

Keep in mind that none of the past couple of days discussions would have taken place if it weren't for the fact that I changed my rig to a balanced lug sail and the freestanding mast.

I was 100% happy with the design parameters for a standard stick and a marconi "sloop" masthead setup, there was no need for more design or drawings, all ok all done, finished.

Thats when I decided to call in the troops again, beg for fogiveness and plead fo assitance on my hands and knees ;)
because we all know a major change like this, so late in the build, is scary.

1 So we went from this "Cordelie"

2 To this "Scamp"

3 a balanced lug

Manie B

03-01-2012, 06:15 AM

oh and just to show that I am not a complete goofball :P
I didn't move the position around of the centerboard ;)

that is the only thing that is millimeter accurate
jeeez thank goodness for that!

Manie B

03-01-2012, 06:23 AM

please you must watch this video of Scamp
this is where the Magic is
take note of how the boom reefing works
very clever

http://www.youtube.com/watch?v=GomIAiuqfws&context=C318c336ADOEgsToPDskJ8Eyjr7BwcZkDXkWx8EV5b

rwatson

03-01-2012, 03:28 PM

Funny you posted the link to your past built because...or, rather let me quote ;)

"I had no plans, just a few pictures of a Wharram Catamaran

It was a lot of trial and error until it worked properly."

Yeah - but you conveniently left off my most pertinent remark

"... which is the reason that my current project is getting the full design completed before a single plank is cut."

I have learned my lesson - Manie is still half way through his . :)

At least Manie did not have trail & error issues - we speculate, then calculate and finally pray before doing it...

No trial and error ? He still has to finagle you into calculating his scantlings for the major structural element of the entire boat (hey, whats the chance of getting insurance on this prototype over there ? ) - so he may be forced to break into his lovingly painted and sanded interior to do some major work. That sounds like fun - NOT!

Then, he still has to sort out the sailplan and all the associated mast and rig setup problems.

Like Manie just said once power supply was restored "because we all know a major change like this, so late in the build, is scary."

If that's not trial and error, what is ?

And Troys comments :-
"It's easy to sit in the shadows and potshot those who are actually doing something...."

Yeah - of course it is - thats why I am doing it !!!

Whaddya ya want ? Do you think I am silly enough to spend 3 years in my carport sucking in sawdust and epoxy dust, and having to keep the place looking like Martha Stewarts show home ?

What fool would do that ? :D

My biggest worry is having Manie out in the shark infested waters of the Southern Ocean with the little putt-putt, a sail rig that is still under test, and 200 kilos of prime steel hanging off his arse that may or may not stay there if the waves and wind get any bigger.

If the worst happened - what a waste of steel and epoxy !!!! :p

masalai

03-01-2012, 04:16 PM

Arrrrgh I would be disinclined to put much in the criticism of RW... No build recorded... - and Australian banks do borrow heavily overseas...

Doug Lord

03-01-2012, 04:35 PM

You've done great, Manie-good luck and good sailing! Maybe I can get my damn boat figured out......

Manie B

03-01-2012, 10:49 PM

rwatson your "concern" is appreciated and ok thats enough now, the comments are going around in circles

rwatson

03-01-2012, 11:36 PM

rwatson your "concern" is appreciated and ok thats enough now, the comments are going around in circles

You're right - however you got there, you are further ahead than 98% of small boat builders. Well done - and you get an "A" for perseverance.

You may not have ticked the boxes in exactly the right order - but you have all the boxes lined up neatly in front of you, which is half the battle.

And as you say - making it up as you go is a lot of fun :)

Wynand N

03-01-2012, 11:41 PM

Manie, you said it well.

Many people are content with their daily grind middle of the road monotonous lifes, living from day to day awaiting their salary pittance on pay day. They conform to what is proven and stay within those "laws" that makes their world go round. It is also called a comfort zone....

The problem with comfort zone holes are although you sit snug in it you views are also limited to the sides and you do not see much else. Getting out of that comfort zone however, the containment sides of the zone give way to a much wider world, challenges etc but since you are not snug in the zone anymore, the ride may be more shaken...
When faced with a bigger vision out of the comfort zone, life becomes more interesting and as mentioned, more challenges there for the taking and suddenly life get worth its time.

Basically all the comforts and technologies we have today and take for granted, is the result of someone getting out of the box and taken some risks. Most probably some of them were laughed at when they build and risk life and limb trying out their ideas. Like the saying goes; "nothing ventured nothing gained" and most of the time that is true.

I had a laugh when reading the concern that you may end up being lunch for the sharks - heck, first off they have to be starving and hard up before attempting to lunch on your bacon:D and at the end of the day, we all have a date with death once in our lives and why not cash that in doing something you like...
In fact, you stand a better chance to get murdered here or being run over by a car than ending up on the sharkie menu.

For what its worth. I once (late 1980's) built a steel boat (design by a well known international design group in Europe) for a client and after the hull plates were done, he wanted a totally different deck for the boat, interior, sailplan etc. and the plans dumped because for what he want, they are now obsolete. At the time I had not done my small boat design diploma yet, IOW, no frickin clue on how much here and there to add or take away, less more so my client, but being a boilermaker by trade, I did the best I could with my knowledge of steel and the boat is still sailing the oceans.
My mentor at the time as a greenhorn boatbuilder, and he a boatbuilder of the old school, the late Ronnie Nel from PE once told me early in my career; "Wynand, if it looks right, in most cases it will be right" and this I found rung true through most of my building career.
Quite often I will make an amendment to some structural part on the spur of moment by the "look right" method and when run a scantling calc on the part later, it would be usually OK or in excess.

Ask yourself this question; before man became clever, using maths, employing computers, how did they know the boat structure will be OK?? I would venture and say the used old Ronnie's method "if it looks right, it should be right".
Also true, most small boats are immensely strong compared to their larger sisters and are usually overly strong built and yours falls definitely in that category.:cool:

Finally, forget the nay sayers, focus on your own thing and if something look and feels right to you, it most probably is. At the end of the day it is you that should be satisfied with the results and screw everyone else.

troy2000

03-02-2012, 12:11 AM

My mentor at the time as a greenhorn boatbuilder, and he a boatbuilder of the old school, the late Ronnie Nel from PE once told me early in my career; "Wynand, if it looks right, in most cases it will be right" and this I found rung true through most of my building career.[/B

Although I'm not a professional boat builder, I've built a lot of houses, garages, decks, sheds and whatever in my lifetime. And I'll agree wholeheartedly with that statement, with one caveat: you need to have enough experience to understand WTF you're looking at!!

Manie B

03-02-2012, 07:27 AM

Although I'm not a professional boat builder, I've built a lot of houses, garages, decks, sheds and whatever in my lifetime. And I'll agree wholeheartedly with that statement, with one caveat: you need to have enough experience to understand WTF you're looking at!!

How true!

I have been thru a very lousy time the past 4 years with many of my very close mates passing away. That is why I decided to start a Facebook page, this turned out to be a bit of a CV and also the history of my working career.
To some this may seem a bit crazy, but I am what I am and did what I did. Some good some not so good.

Anyway this is the "info paragraph" from Facebook

I have started this Facebook page to try and find some of the old friends and colleagues that I have worked with over the years. There were many good days and some seriously pleasant memories. Love to know how all of you have held out and hoping you are healthy and well.
I have been in my own businesses since approx. 1980 and still at it! I still dream of sailing solo around the world one day!
Read all about my hobby at www.compaxboats.wordpress.com

You can read more on Facebook - it is open public knowledge - got a bit of experience ;)

Manie Botha

http://www.facebook.com/profile.php?id=100003491689969

Wynand N

03-02-2012, 01:40 PM

Manie, just browsed your keelbox installation on your blog and glad to say that I am overly impressed with that piece of engineering :cool:
http://compaxboats.wordpress.com/2011/08/13/center-board-casing/

It is in fact - by just looking at it, overly designed to support a small 160kg bulb hanging 1.1 meter below bilge. You did good by reinforcing the whole area with Kevlar etc and I like the fact the casing protrudes 25mm through hull. Also nicely supported at the top and the fact that the casing also protrudes 25mm through the deck - the keel has to move the deck before that case moves.
Furthermore it is solidly bonded and supported by the two main transverse bulkheads vertically fore and aft of keel box that will distribute loads imposed by the keel over large areas of the hull. The furniture (locker) that is attached to the casing about midway up and also solidly bonded to the two mentioned bulkheads and the hull side further stiffen it up immensely and all work very neatly done:cool:

This is what I call a decent piece of (engineering) design and execution thereof and most likely way over designed for what it suppose to do.
However, I think you must rather spend your energy now on designing a decent centreboard that will handle the bulb safely without breaking. Think steel (ss) reinforced and carbon fibre unit...

Just my sentiments for what its worth

Angélique

03-02-2012, 04:08 PM

Hi Manie, congratulations on the outcome of the stability calculations http://www.boatdesign.net/forums/images/icons/icon14.gif

About the bulb, 160 kg requires 20.3 dm³ steel or 14.1 dm³ lead. Maybe someone can estimate or calculate how much the bigger steel bulb vs a lead one will slow you down. If not much, no problem. If more, you might reconsider . . . . ? ?

Question about the stability, one of the advantages of a centerboard is you can pull it up in a gale to be able to be pushed aside by the seas rather than trip over the board/keel which causes the knock downs when the sails are down. In this case you also pull up the ballast. What would be the stability with the board up ?

Wynand, please keep up the good work :)

Cheers,
Angel

Angélique

03-02-2012, 04:32 PM

BTW, saw Dudley Dix uses beavertail bulbs (http://www.google.com/search?q=beavertail+site%3Ahttp%3A%2F%2Fwww.dixdesign.com%2F) rather than pointy ones.

http://www.dixdesign.com/didi28%203D2.jpg
Didi 28 (http://www.dixdesign.com/28didi.htm)

Is there someone who can tell me the benefits of beavertail vs pointy ?

What form are you gonna use Manie ?

Good luck !
Angel

Manie B

03-02-2012, 11:35 PM

The centre board was the first item that I built before I even started with the boat.
Because from that I built the "casing"

The center board is

6x layers of 9mm marine-ply laminated
1x center core of carbon fibre
2x outer cores of kevlar
2x far outer cores of 600gm bi-ax glass

and then the whole lot wrapped in 750 gm glass

Manie B

03-02-2012, 11:37 PM

The "design" of the lifting centerboard was primarily for towing, the added bonus was to be able to go motoring into very shallow water.

see post #9 and #10
jeez this thread has been running so long that we all forget where it started :P :P :P

Manie B

03-03-2012, 12:01 AM

Angel we did look at the size of the bulb - steel vs lead
the problem is lead is so insanely expensive here that it is not an option
and I was very fortunate that Colin could get the Re-bar offcuts at scrap prices, because even using new steel square bar would cost an arm and a leg

Manie B

03-03-2012, 12:10 AM

i found a nice pic of the centerboard wrapped in glass
Naca 63-012
400mm wide x 45mm thick finished sizes

Wynand N

03-03-2012, 01:19 AM

Question about the stability, one of the advantages of a centerboard is you can pull it up in a gale to be able to be pushed aside by the seas rather than trip over the board/keel which causes the knock downs when the sails are down. In this case you also pull up the ballast. What would be the stability with the board up ?

Anything for a nice lady Angel since you asked :cool:

Since I have everything already, I just raised the keel CG on the spreadsheet and measured the new righting levers on the plot and presto ;)

As mentioned before the boat has a lot of initial form stability and it shows at lower angles up about 20 degrees of heel.

Vanishing stability dropped from about 136 degrees heel to 118 degrees which is not all that bad either.
The positive to negative and vice versa roll ratio dropped from 4.9 to 2.75, IOW more difficult to right itself when turned turtle with keel up.
Maximum righting moment dropped from 50 degrees of heel to 40 degrees of heel with keel retracted fully.
GM (metacentre) dropped from 0.810m to 0.650m at 30 degrees of heel.
VCG reduced from 1.704m max draft to 1.872m with keel fully retracted. (measured from keel bottom)

Overall the results are not bad with the bulb keel fully retracted and a lot of cruisers are sailing the big blue pond with similar figures safely...

Angélique

03-06-2012, 11:17 AM

Sorry to hear about the excessive lead prices in SA Manie, maybe better make it of gold then, you only need 8.28 dm³ of that so the boat will be even faster . . . . :p

This shouldn't be a problem for the big sponsored ocean racers, and as a side effect it wouldn't leave any wrecked racers on the ocean floor. . . . . . :P

Anyway, when extrapolating historical development, a lead or gold bulb would be the only part of the boat that keeps increasing in value, so aside from the sailing benefits it could be a sensible investment . . . . two remarks on that sense though, it needs to be affordable now and the investment has no financial benefits to the investor if the boat outlives him, so steel seems to be indeed the logical choice here . . :(

Cheers,
Angel

P.S.

What about a wrecking a discarded "free" boat for the lead, or do they all have steel or concrete ballast instead of lead in SA... or would disposal of the rest material be too expensive . . . ? ?

https://lh5.googleusercontent.com/-nDnmfhrs9Dg/SIi7FcWPLXI/AAAAAAAAA58/vTMiMoz9Pz8/s640/100_2236.JPG

https://lh4.googleusercontent.com/-8IARVnT0w7I/SIi7HFmfI-I/AAAAAAAAA6E/PfizYjks4NA/s640/100_2266.JPG
click for source (http://www.magma.ca/~ovenden/Ballast.html)

-- from forum members M&M Ovenden (http://www.boatdesign.net/forums/profile/m-and-m-ovenden.html) -- new link (https://sites.google.com/site/pepeberrou/ballast) to pic source --
.

Angélique

03-06-2012, 11:51 AM

About the beavertail bulb question in post #613 (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-41.html#post535513). I wasn't asking about the aft end of the board, but was asking about the aft end of the bulb, just digged into the forum and found this about the subject...

(from some different threads, click on http://www.boatdesign.net/forums/images/buttons/viewpost.gif in the quote if you want to go to that thread & post)

http://www.sponbergyachtdesign.com/Designs/PA3.jpg
click for source (http://www.sponbergyachtdesign.com/ProjectAmazon.htm)

From a purely hydrodynamic point of view the bulb is detrimental. But if you have to have a bulb, then it needs to be integrated to produce the minimum drag. One way to do this is to use the bulb to extend the effective span of the keel, as long as the wetted area isn't increased too much. That's what winglets and beavertail bulbs are all about.

The chine runner would act much like the beavertail seen on bulb keels, in regard to what it does to flow. A curved chine runner would have a small envelope of effectiveness, but if the hull was held at that particular angle, she'd perform some work, though, again not a substitute for proper appendages.

The SC 40 is modelled on the same lines as the Skerry Cruisers, which celebrate their 100th birthday this year (2008). The hull is long and narrow with long overhangs. Everything else, however, is a little different. The SC 40 has a lifting keel, lifting rudder, and a free-standing wingmast rig. The boat will be built in China and shipped on its own trailer complete in a shipping container. It is quite a viable boat-in-a-box.

At the request of the client, we have designed two versions. The first is the Sport Cruiser which has the longer coachroof and shorter cockpit. The Day Boat has a shorter coachroof and longer cockpit. Drawings and renderings are posted here. The renderings are completely computer generated and they show the Sport Cruiser. The sail plans of the two versions are shown here, and we are working on the renderings for the Day Boat. You can see a more complete story of the design on my website at:

http://www.sponbergyachtdesign.com/SC40.htmsmall quote from Eric's above link, but better read the whole page there
----------------------------------------------------------------------------------

http://www.sponbergyachtdesign.com/Designs/SC40-DB%20GA%20PROFILE--REV%20E.jpg

http://www.sponbergyachtdesign.com/Designs/SC40-DB%20GA%20SECTIONS--REV%20E.jpg

The bulb shape is a flattened bulb with a scalloped and flattened tail. It is positioned such that the nose of the bulb is ahead of the keel blade leading edge. The position of the keel in the boat and the position of the bulb on the blade are absolutely critical to the flotation and the proper sailing performance of the boat.

The keel on the SC 40 is a constant section modified GA(W) aerofoil of 10% thickness. The rudder is the same section, by the way, just scaled down. The keel has to be a constant section so that it fits properly in the keel casing (close clearances) inside while it slides up and down.

The bulb is shaped to what I call a Beavertail/Swallowtail bulb (BS bulb, for short--I like the pun). The Beavertail aspect--flat beavertail shape on the aft end--is to form an end plate for the keel blade. Without an endplate, the flow across the keel will tend to slide down the keel and off and under the tip, thereby creating a trailing vortex. The creation of the tip vortex is the very essence or signature of induced drag. The bigger the tip vortex, the more non-uniform is the flow over the keel, the higher is the induced drag. The more you reduce the tip vortex, either by planform shape, foil twist, or by end plate, the lower is the induced drag. Therefore the keel is more efficient. Efficiency is defined as the lift-to-drag ratio, L/D. With lower induced drag, there is less force holding the boat back in speed made good to windward (VMG), therefore the boat is faster in VMG.

Another way to reduce tip vortex is to change the keel planform shape, either to a more elliptical shape, or by twisting the keel section so that the leading edge of the keel actually points a little to one side. Well, with a lifing keel, you cannot use an elliptical planform shape because in a raised position the keel does not fit snugly into the hull. And you can't twist the keel because it has to work on both tacks. To try to twist the keel while underway would be a mechanical nightmare. So for a lifting keel, you are left with a constant section and constant chord length, and you have to fit it with an endplate. Since the boat's stability favors and requires a low center of gravity, it is natural to make the end plate a ballast bulb. This, you can see, helps me have a range of stability (AVS = angle of vanishing stability) of 180 degrees. This is very rare in yacht design. I achieve the same thing on my design Saint Barbara, which you can also see on my website.

As to the swallowtail feature, flat and square-cornered plates shed their own vortices and create induced drag. Theoretically, one can conceive of a keel design whose endplates have endplates, and then those endplates have more endplates, ad infinitum. You'd actually be overcome by form drag and delicate shapes very quickly. But subsequent to the 1983 historic loss of the America's Cup to the Australians, the Americans did a broad array of studies on keel shapes, winglets, and endplates, and they discovered that if you sweep back the tips of the corners of the endplates into a swallowtail shape, you actually reduce the size of the tip vortex, thereby reducing the endplates own induced drag. So I started putting swallowtail shapes on by beavertail buld designs and came up with the BS bulb. The above is NOT BS, by the way, you can look it up, and there is foundation for the science.

I might add that you could conceive of a keel with no bulb, but with a scimitar-shaped tip wherein the tip of the keel (or rudder) is swept aft. This, in fact, is becoming more common. One sees it in airplane propellers a lot these days, and you also see it in the tips of windmill turbine blades. Also, you will notice in my rudder designs, including that of the SC 40, and on Saint Barbara and Bagatelle, that I sweep the leading edge of the tip of the rudder aft. This is contrary to older rudder and keel designs of the 1980s and 90s where, instead of the leading edge at the tip sweeping aft, the trailing edge is swept forward. This is an effort to approximate an elliptical planform shape which tends to give the rudder an elliptical lift distribution along the span, which creates the least amount of tip vortex, and therefore has the lowest drag. This is true in concept. But I am of the opinion that such rudders (and keels) with swept-forward trailing edge tips are actually backwards. Rather, the planform shape should be flipped back to front, thereby giving a more scimitar shape to the planform with a swept leading edge tip. This will be a lower drag shape than the reverse.

Have a look at my website, www.sponbergyachtdesign.com, and go to "Repairs and Modifications". You'll see a keel repair project on a Cambria 44 called Magic, where we cut off the tip of the keel and replaced it with an equal amount of lead in a bulb shape. My bulb designs typically are oriented at the aft end of the keel tip, as on Magic, and I make the trailing edge of the bulb in a flat shape like a beaver's tail, and the aft edge scalloped shape as in a swallow's tail. Hence I call these bulbs beavertail-swallowtail bulbs, or B-S bulbs for short (pun intended). But they have proven very effective in many of my designs. The owner of Magic reported that the boat pointed a few degrees higher and sailed a tad faster--1/4 to 1/2 knot or so, because of the reduced drag of the keel.small quote from Eric's above mentioned Cambria 44 MAGIC (http://www.sponbergyachtdesign.com/Magic.htm) project, but better read the whole page there
-----------------------------------------------------------------------------------------------------------------------

http://www.sponbergyachtdesign.com/Repairs/KEEL3.jpg

I call the bulb design a beavertail-swallowtail design, or a BS-bulb for short (go ahead, you can chuckle). This is because of its flat aft end (like a beaver’s tail) that terminates in a swallowtail shape. The shape and position of the bulb minimizes the tip vortex off the bottom end of the keel, thereby improving lift and decreasing drag. After sailing trials, the owner reported that MAGIC sailed faster and pointed higher than she did before, and she had reduced draft to boot.

Hope this clarifies the question in post #613 (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-41.html#post535513), what bulb form are you gonna use Manie . . . . :)

Good luck !
Angel

Fanie

03-06-2012, 11:52 AM

Geeezzzzz Manie, all this could have been saved by a multihull :D

Angélique

03-06-2012, 12:45 PM

Geeezzzzz Manie, all this could have been saved by a multihull :D

Yeah, that would leave you with two cramped spaces to small to live in instead of one livable small space . . . . :p

Rory lives a lot on deck and often in a dry suit (website (http://roryandcookie.com/) - blog (http://roryandcookie.blogspot.com/)) . . . . :idea:

Cheers,
Angel

P.S. - I've added a P.S. about the lead to post #619 (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-42.html#post536548).

Fanie

03-06-2012, 01:06 PM

Yeah, that would leave you with two cramped spaces to small to live in instead of one livable small space . . . .

Utter nonsense ! At 1m200 wide and as long as you want it can be made perfectly trailable and wide enough to be comforatable. While you now have two private-from each-other-berthing you also have a deck which is the outdoor area.

Of course if you go THAT small nobody can help you, as a girl you should know that small is no good :D I actually drawed a cat at 7 inch... I mean meters that can be made to work with the basics to stay on the water for a week, at 8m it becomes much better and at 9m or more it gets roomy, you run out of things to put in it.

Why do you want to sleep abeam in a boat ??? :D

Fanie

03-06-2012, 01:19 PM

Here is the basics... http://www.boatdesign.net/forums/multihulls/fanies-folding-cat-41948.html

Angélique

03-06-2012, 01:32 PM

Hey Fanie,

Manie likes small, don't know about his missus but I bet she doesn't like the boat . . . :p

I wrote about size here (http://www.boatdesign.net/forums/wooden-boat-building-restoration/excelsior-atkin-cruising-canoe-35365-5.html#post535552) ;)

Here is the basics... http://www.boatdesign.net/forums/multihulls/fanies-folding-cat-41948.htmlIs that the same as this one (http://www.boatdesign.net/forums/multihulls/boxy-fisher-catamaran-26429.html) or a new project . . . ? ?

Cheers,
Angel

Fanie

03-06-2012, 01:42 PM

Almost yes, but nothing in this horrid place goes as planned :(

Hey Fanie,

Manie likes small, don't know about his missus but I bet she doesn't like the boat . . .
LOL, I'm not going to say anything. Manie won't be alone though, I'm sure there will be other sailors on the water as well... :D

Angélique

03-06-2012, 04:47 PM

http://www.boatdesign.net/forums/attachments/all-things-boats-and-boating/48770d1287503445-where-ok.gif
Wynand, thanks for the extra stability calculations (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-42.html#post535594) and all the other info, it looks good for Manie . . :)

So I guess one can experimentalize in the described (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-41.html#post535507) situation what board position suits best there.

It would be nice though, in the event of a capsize with the board up, that the board could be raised (think upside down here) in the inverted positon to put the boat back on her feet.

Manie, an other thing, will there be a facility that locks the board in its position, so the bulb won't fall on the bottom in case of a roll over with the board down ?

Sorry for these horror scenario questions, but they keep bothering my worried mind . . . . . :rolleyes:

Good luck !
Angel

Manie B

03-07-2012, 06:08 AM

Angel, nice info there - good reading!

so the bulb won't fall on the bottom in case of a roll over

:) dont worry got that covered
that is where my "neatness" helps a lot - nothing but nothing will be out of position when she's upside down
everything is secured
I have read way to many stories of food and pasta and knives and forks flying all over the show and then when the boat goes back upright all the "loose" items block the bilge pump
now you can understand why I have all these plastic crates that fit in every where

everything in a box :cool:

the new clear boxes are fantastic - you can see what is inside - like food items

Manie B

03-07-2012, 12:47 PM

:p

well folks
amongst all this flurry of exitement

:D

'whew' all the questions and what not

:cool:

we know it floats (huraay huraay)

:P

with a bit of luck she will stay upright

:P

with even MUCH more luck she MAY right herself

:eek:

and now (drumroll) she's LEGAL

YEAH MAN

troy2000

03-07-2012, 01:51 PM

WestVanHan

03-07-2012, 10:00 PM

Yeah, that would leave you with two cramped spaces to small to live in instead of one livable small space . . . . :p

Hey Angelique...for your viewing pleasure a member has some interesting small cats:
http://www.ikarus342000.com/CATpage.htm

Congrats Manie...

Doug Lord

03-08-2012, 07:42 AM

One more step- congratulations!

Angélique

03-08-2012, 11:32 AM

:D a bulb keel :eek: anxiety

http://www.boatdesign.net/forums/attachments/boat-building/67888d1330591246-manies-microcruiser-pics_052_clean_638.jpg

And... that isn't even photoshopped ! ! - - http://www.boatdesign.net/forums/images/editor/youtube.gif Alex Thomson - HUGO BOSS - Keel Walk (http://youtu.be/B2PQfJ2SAg4)

Btw, I guess there's a pointy ended bulb here, rather than a Beavertail-Swallowtail (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-42.html#post536552) design, as the transverse position of a BS bulb on a canting keel doesn't stay parallel to the bottom of the boat, expert opinions welcome on this . . . . . . :)

Cheers,
Angel

troy2000

03-08-2012, 01:24 PM

And... that isn't even photoshopped ! ! - - http://www.boatdesign.net/forums/images/editor/youtube.gif Alex Thomson - HUGO BOSS - Keel Walk (http://youtu.be/B2PQfJ2SAg4)

Btw, I guess there's a pointy ended bulb here, rather than a Beavertail-Swallowtail (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-42.html#post536552) design, as the transverse position of a BS bulb on a canting keel doesn't stay parallel to the bottom of the boat, expert opinions welcome on this . . . . . . :)

Cheers,
Angel

I enjoyed that, and was amazed by some of the sour, wet-blanket viewer comments....

Manie B

03-08-2012, 11:20 PM

Jeez Angel, what a video, thanks for the post

brilliant :D

Angélique

03-09-2012, 11:03 PM

Hi Manie,

There's an old ferro-cement boat in Richards Bay to be scrapped and stripped off her ± 5 tons of lead. The new owner might have a surplus, see this thread (http://www.boatdesign.net/forums/boat-building/what-do-new-tmd31n-volvo-engine-42165.html) if interested. Maybe the top end of one of the masts is interesting too . . ? ?

I know it's about 650 km SE of you, but they might be willing to send it over . . ? ?

If getting a deal from this you'll need some extra lead for the risers and maybe also some extra for any contaminants that will float on the melted lead in the melting pot and can be skimmed off before pouring, think Colin can tell...

Good luck !
Angel

P.S. - Timo's ballast pouring (http://www.byyb.org/forum/index.php?topic=2466.30), some went well, some not so . . . . :idea:

Manie B

03-12-2012, 03:50 AM

Good news :D

Special Video for all the folks at Boatdesign.net
http://www.youtube.com/watch?v=korQgkY9HS8&context=C40500faADvjVQa1PpcFMqorUAmB0Nq7KjgB8OY2I2W0DRFmdcf6Q=

:D :D :D

I spent the weekend at Hartbeespoort dam, really great fun. The motor runs like a dream, one pull start, anywhere anytime, the fuel pipes are working and the "Hand pump" is upright. What is really amazing is that she runs at 2.5 to 3 knots at around 2000 rpm. WOT at 3900 rpm gives approx 5.3 to 5.8 knots. I could go for a smaller prop but I wont do that, at low rpm I get excellent thrust, good speed and fantastic fuel consumption. The motor absolutely "purrs" at low RPM. I have one of those electronic RPM devices that you clip onto the spark plug wire. I guess that I have only used 5 liters (half a gallon) for the whole day at about 7 hours continous use.

Hartbeespoort was the first one on my "bucket list" I used to live there in a suburb "Ifafi" when the kids were still at primary school. I really wanted to see the place after all these years. I intend to motor around some of the local dams before the keel and mast goes up and the boat becomes heavier. Hence the "bucket list"

Just for the guys in Saffa - the area is beautiful and where I was at Meerhof boat club I was very safe. The local fishermen are well equiped with "night vision" scopes and what not else :eek: These guys are a combination of "Rednecks" and the Klu Klux Klan - NOBODY BUT NOBODY comes near them :D so as an Afrikaner "Oom" I was well protected and safe to sleep there. These guys fish and drink all night so no problems there;) Always somebody on "guard duty"

BUT

The water is FILTHY - it is a complete sewer. During the night there was a big storm in Johannesburg and TONS of junk came down surrounding my boat. By morning it had cleared and I made my first coffee anchored out towards Ifafi. It took me the whole of Sunday afternoon to scrub the oily messy grime of the boat. The growth of algae is insane - like thick pea soup in places. The Hyacinth that you see around the boat is waist high and there is an oily film on the water. When the wind blows in your direction its simply time to pack up.

What is amazing is that some fish FLOURISH in the grime. The guys are catching big carp and often.

So motoring around was fun, I cooked "manly" meals = chilli stews :D and a good couple of whiskeys before bedtime. Loved it - enjoyed it - beautiful mountains - been there - got the "T" shirt and wont go back.

Manie B

03-12-2012, 04:01 AM

Hartbeespoort Dam

Wynand N

03-12-2012, 06:33 AM

I envy you Manie...:)

But your pics bring back memories of Harties. When I was I youngster during the 60's and early 70's my late farther and I spent most of our weekends at Harties fishing and our favorite spot use to be Meerhof where your boat was tied up for the night. However, at that time Meerhof was a farm and none of the beautiful wall and lawns were even a distant thought in someones mind - fishing was good, especially for Kurper (bream) and the dam was clean and free of water Hyacinth at the time.

Looking at picture seven and the train bridge in the background - also a favorite fishing spot of the old man and I and having spent a 2 year stint on the railways as a fireman stoking steam locomotives (every young mans dream) we passed with the locomotive over that bridge everytime we did the Pretoria - Harties trip and the engine was turned, firebox cleaned, back over the bridge back to Pretoria. That rail line incidentally, is a narrow gauge and used a smaller engine than most other lines. Then progressed to diesel locomotive and the the army got hold of me and gone my rambling railway days....:(

Cosmos was also non existent, and so all the housing projects shown on the satellite picture. Hartebeestpoort dam used to be surrounded by farms and small holding in the days I wear a younger man's clothes. Passed Harties about about a year ago on the old aquarium road and was shocked to see the place all built up, shopping centres etc etc - scared the living daylights out of me.:D

Thanks for the memories. :cool:

These guys are a combination of "Rednecks" and the Klu Klux Klan - NOBODY BUT NOBODY comes near them so as an Afrikaner "Oom" I was well protected and safe to sleep there. These guys fish and drink all night so no problems there Always somebody on "guard duty"

That's exactly the why reason the place is so clean and neat. You know all to well what happens when blacks are present - filth and strewn rubbish rules, tires will be stolen for taxis, urine will cover the trees, need I go on?
Sorry folks, this is not a political statement but a fact of life in Saffas land and we experience this on a daily basis everywhere.:mad:

Doug Lord

03-12-2012, 07:34 AM

Thanks for the video ,Manie! Great to see you on the water....

hoytedow

03-12-2012, 07:58 AM

Great post and video, Manie!. That hyacinth has been a bane on Florida waters since some lady decided she liked the flowers and imported them. I have seen the Hillsborough River and other water bodies here choked with them.

http://plants.ifas.ufl.edu/node/141

Manie B

03-12-2012, 09:08 AM

Here is the "nice" video of the boat running at around 3,7 knots and the motor just on a fast idle, you can see that the throttle is not yet on the start position !!

Beautiful smooth wake - that shows that fiddling with Freeship for months and months does have some merit :cool:

http://www.youtube.com/watch?v=iF8H67nLVZ0&context=C40500faADvjVQa1PpcFMqorUAmB0Nq7KjgB8OY2I2W0DRFmdcf6Q=

Wynand N

03-12-2012, 01:09 PM

Great videos :cool:

Folks, since I know Manie personally and looking at him narrating about the boat in the first video, I immediately noticed Manie is at peace with himself....

It seems like yesterday when Manie visited me for a weekend and this guy had this idea of a boat he want to build. We discussed it in length with firewater and spent quite a bit of time around the BBQ fine tuning ideas. What impressed me was the drive and enthusiasm Manie had about this boat - a far cry from the Manie I knew from a previous overnight stay.
He believed in his idea and himself so I gave him a little advice (not that I can contribute a lot) , some software and some boat design handbooks and sent him on his way.

During the build I visited him twice and Manie was over the moon seeing his vision taking shape - always explaining his reasons for this and that and finally it has now all came together and the little left to do is just detail.

And what a boat it turned out to be and Manie has the right to be on top of the world. He dreamed it, designed it and now enjoying the fruits of that.
He did it the hard way; built a little Portuguese dinghy as a starter project to get the feel of wood, then build two catamaran hulls (I am the proud recipient of both these fruits of labour) and "served" his apprenticeship as an amateur plywood builder. By gaining the necessary confidence and experience with these two past projects, he started what he always wanted to do and did it.

Manie, I salute you :)

Doug Lord

03-12-2012, 02:43 PM

I second your salute! Manie, taking an idea from the firewater stage to the video you just showed us is an awesome accomplishment-way to go!
Now have fun......

Manie B

03-19-2012, 07:43 AM

Well folks I went out again to the Vaaldam. I am now 100% confident that my motor and fuel systems are 100% good and 100% reliable. The motor starts one pull anywhere anytime. That after running out of fuel and switching over to the other tank. I also ran the Minnkota for an hour. I got on the boat Friday afternoon and only got off Saturday lunch time. The only way you get the real feeling for a "Man Cave" is when you cook, eat, drink, sleep, "poo" in a tiny nutshell. All good and after I slept at anchor in Anchor Creek and am totally happy. All is tested and now I can move forward to the new projects with confidence. I will invite all the friends to come down once the centerboard and bulb keel is fitted. Running without ballast is not clever and I wont do that with any passengers on board.

Fanie

03-19-2012, 01:51 PM

Running without ballast is not clever and I wont do that with any passengers on board.
Yeah, or else it may stay afloat if it gets holed !

Nice going Manie ! Proud of you mate.

masalai

03-19-2012, 03:35 PM

Congrats Manie,
Some images of you blasting around with bulb keel and sails would be great - and some close-ups of the HUGE grin of pride and satisfaction on your face... bon chance.....

Manie B

03-20-2012, 02:24 AM

:) When Fanie phoned me last night he was "refering" to the black bucket on board. Well here it is in all it's glory. I like having a nice comfortable wooden seat in the morning with my second cup off cofffee :D

sorry folks this could be a bit of information overload :eek:
but we cant forget the "teaspoon affair" :idea:

and anyway any decent yacht should have a plan "B"
plumbing and pipes have a nasty habit of blocking;)

Fanie

03-20-2012, 05:00 AM

Hi Manie,

What you should do is get a proper toilet seat with folding lid.
When you're not sailing you hang it on the lounge wall.
You put mother-in-law's picture in there, only when she visits, you close the lid ;)

It seems that bucket is a real multifunction tool.
It's a bailing bucket,
the on board shower,
clothes washer,
chum bait with it when fishing,
the wash-your-face and toothbrush basin,
a hat when it hails,
upside down it makes a small dining table,
it is a weapon to hit pirates when they attempt to board,
a drogue in bad weather,
in case of a MOB, upside down it's flotation,
in rain it's a freshwater collector.
and as shown it even makes an extra seat in the boat ;)

Such an important tool Manie - I'll seriously consider giving it permanent flotation... at least insure the bloody thing.
When you go sailing you should carry it on your person at all times :D

Oh and by the by. You should maintain the forward V in the bucket shape. The once in a blue moon IF something comes up you don't want to be stuck hooked to that seat...

masalai

03-20-2012, 07:38 AM

I am a little concerned when in a case of urgent need,
- one is inclined to sit down in a hurry so as to avoid spreading,
- what is supposed not to hit a fan,
- as that flimsy bucket collapses
-
-
- Ahhhhhh I get it, "A bucket load of laughs....." :D :D :D :D :D :o

Manie B

03-20-2012, 07:43 AM

;) the bucket is actually very strong, it's used on construction sites to mix tile cement and grouting in :idea:

Manie B

03-20-2012, 08:04 AM

Guys my neighbour (that is a non sailor pensioner) had a puzzled look on his face when he inspected the bucket

so just for the record I explained

scoop up a half a bucket of water from the river / dam / sea
sit down enjoy the "second" cup of coffee
wipe bottom with toilet paper
empty the bucket overboard
and the bucket stays clean - as easy as that

:eek:

now blow me away
a 70 year old neighbour that has NEVER used a bucket

sailors are most definately different from "city folks"

the1much

03-20-2012, 09:24 AM

dang that syle,,, our bucket had no bottom, hung over side,,make sure you got strong legs and well sense of balance,, hehe ;)

Fanie

03-20-2012, 09:31 AM

LOL Toomuch, pointing in the right direction it could actually increase speed eh ;)
And with a lighter the boat could become a rocket ! We all know displacement hulls can plane.

I am a little concerned when in a case of urgent need,
- one is inclined to sit down in a hurry so as to avoid spreading,
- what is supposed not to hit a fan,
- as that flimsy bucket collapses
-
-
- Ahhhhhh I get it, "A bucket load of laughs....."

How about there is a hole in the bucket dear Liza !
Mas, you take the false teeth out first if you have to use it urgently. You forget this only once...

I can confirm what Manie says about the bucket, we use them here by the house ourselves :D

They are very strong and thick.
And we use our's for building, of course ;)

Fanie

03-20-2012, 09:42 AM

The list of uses updated =

It seems that bucket is a real multifunction tool.
It's a bailing bucket,
the on board shower,
clothes washer,
chum bait with it when fishing,
the wash-your-face and toothbrush basin,
a hat when it hails,
upside down it makes a small dining table,
it is a weapon to hit pirates when they attempt to board,
a drogue in bad weather,
in case of a MOB, upside down it's flotation,
in rain it's a freshwater collector.
and as shown it even makes an extra seat in the boat
Soak teeth in it overnight.
You can scratch that difficult to reach spot on your back with it
Holds the soapy water to scrub the bird poop off the deck
Kitchen sink to wash the cutlery in.

the1much

03-20-2012, 09:58 AM

other uses
hide whats left of ex,, this goes with the chumming.
brake on boat
use so you can hear your echo when hollering in it.
put up to ear and you can hear the ocean
use as emergency sail
to wade in without getting outta boat....... ;)

Fanie

03-20-2012, 10:07 AM

How about scooping water up in front of the boat and pouring it out the back... that'll get it moving. It's GOT to move. Or just use it as an oar...

hoytedow

03-20-2012, 10:35 AM

LOL Toomuch, pointing in the right direction it could actually increase speed eh ;)
And with a lighter the boat could become a rocket ! We all know displacement hulls can plane.

How about there is a hole in the bucket dear Liza !
Mas, you take the false teeth out first if you have to use it urgently. You forget this only once...

I can confirm what Manie says about the bucket, we use them here by the house ourselves :D

They are very strong and thick.
And we use our's for building, of course ;)http://www.youtube.com/watch?v=0bS27bjF8Sw&feature=related

masalai

03-20-2012, 06:05 PM

for ANGELIQUE-O.wmv http://www.youtube.com/watch?v=2ZSYTHKZX9c&feature=fvst

http://www.youtube.com/watch?v=mqrfDho4Ucg is for me 'Cocoanut Woman '

troy2000

03-29-2012, 04:43 PM

Don't forget Hank Williams, singing 'My Bucket's got a hole in it.'

http://www.youtube.com/watch?v=Gzzd5PMdOzw

hoytedow

03-29-2012, 05:16 PM

http://www.youtube.com/watch?v=ZhFw8OlCBJw

WestVanHan

03-29-2012, 11:40 PM

Bring me a bucket:

http://www.youtube.com/watch?v=J1C0AsEOYvI

hoytedow

03-30-2012, 06:28 AM

Tampa 2008

http://www.youtube.com/watch?v=BG9lnYMcbaM&feature=related

So, Manie, will you be on your boat this weekend? If so have a nice time.

Frosty

03-30-2012, 11:06 AM

So, Manie, will you be on your boat this weekend? If so have a nice time.

Don't believe it Manie --its a trick. Check the hatch for sellotape and wires N stuff and make sure the gas is of before you light a cigarette.

the1much

03-30-2012, 11:33 AM

http://i1048.photobucket.com/albums/s378/themuchhippie/floatingdistrict46.jpg

Manie B

04-01-2012, 09:27 AM

Oh dear, the boat wont see the water soon. Reason being that I am working every night and weekends on it to get the interior finished.

The story that the pictures cant tell is that I am sitting with an half empty shell. The outside looks ok but the inside is far from finished. Now that I have slept the two weekends on the boat I really want to get the inside done. This is getting all electrics working, fans, lights, stereo, computer, internet, fish finder, Garmin GPS, solar panels, THE WHOLE BANG SHOOT. I really enjoy my boat BUT it will be super cool when all the "gadjets" and "entertainment toys" plugged in.

The next step that will happen alongside all af the above is the "Sailing" part of the boat.

The centerboard is almost finished but I still have to do the "Bulb" and the lifting mechanism.
Then the 2 rudders and tiller steering system.

Last but not least is the mast and tabernakel.
As you guys have gathered by now I am going for the Balanced Lug Sail.
Dries was so very kind to do the calcs for me on the mast, based on the righting moments that Wynand did. It clearly shows that a standard 4" dia x 1/8" aluminium tube wont do the job and will fail at around 85% of righting moment.
So I am definately going for a "Birds Mouth" hollow wooden mast made from Oregon Pine. Fortunately Dries found a local supplier that has stock for me. The irony is that I can build a wooden mast that weighs the same as an alum tube at the same price with much higher strength.

So folks there is the current program, it will probably change when the longing for the peace and tranqulity of sleeping on the hook gets too much, but I will give it a go and see how far I get before the real cold sets in.

Good reading
http://www.diy-wood-boat.com/Mast.html

;)

Fanie

04-01-2012, 10:27 AM

Oh dear, the boat wont see the water soon. Reason being that I am working every night and weekends on it to get the interior finished.

Liar liar pants on fire ! It's getting winter here and we know you are going into hybernation soon...

The 'hollow' wooden mast is an interesting idea, I didn't give it any thought before.

Fanie

04-01-2012, 10:29 AM

The1much, that picture is almost the boat I expected Manie to build, he was into bath tubs at one stage :D

masalai

04-01-2012, 07:09 PM

Hoyt, Frosty, and the1much,
I posted on your rep but forgot to sign, but I am still constrained and cannot give to Manie for his excellent work... 'bugger'.............. I remembered to sign for Westie though...

Wynand N

04-02-2012, 12:19 AM

The 'hollow' wooden mast is an interesting idea

When I first suggested a hollow wooden mast to Manie, he was against it and and firmly believed in the aluminum gospel...:confused::D

Manie B

04-02-2012, 01:00 AM

When I first suggested a hollow wooden mast to Manie, he was against it

True

I was worried about adding more work to an already longwinded project,
but,
as I am going along, I still have a "bucket" :) full of work anyway, so the mast is not going to make that much difference anyway

Or as Dries put it so eloquently the aluminium "sal sy gat sien"
so my options went out the window with that anyway

One really good thing is I love to work with the wood and a wooden mast is sooooooo pretty :cool:

Manie B

04-02-2012, 01:03 AM

Thought for the day ;)

Manie B

04-21-2012, 09:00 AM

Well at last, I can get back to my boat again.
I always have to ask myself "can I do that"
reason being that I dont have a workshop full of smart machines, so all of it has to be done with hand tools.
I got a 3/4" (19mm) router bit "V" groove, and mounted my router upside down on a makeshift framework - well it takes time to set up but jeez it works well.
Only BIG problem is the dust. My dust control and vacuum setup will need some serious consideration and modification.

So here is my birdsmouth "experiment" with some offcut meranti
It really works well, slow yes, but a first class product.

Next month I will get the Spruce and off we go!
Also reached the milestone of 1000 pictures of the build since day one.
so here is #1000 and #1 side by side :)

Charly

04-21-2012, 04:34 PM

Hi Manie, That looks exciting! I will be watching with great interest. I saw a you tube clip somewhere of a family building a wharram cat, and they did the birdsmouth mast. Have you seen it? Seems to me the trickiest part will be to cut absolutely uniform tapers in each stave. How is that done?

Fanie

04-21-2012, 11:27 PM

Just for the illiterates that does not understand Afrikaans
"sal sy gat sien"
translated it means ' shall his hole see'.

Who wants a bare wooden mast of you can glass it and paint it ? You can spend each eavening with touch-up paint to keep it pretty.

Manie you're a real pain in the whatsmecallit with that clean workshop of your's. Come on man give it a bit of character ok, no one's going to believe you built a boat in there.

Angélique

04-25-2012, 08:54 AM

So here is my birdsmouth "experiment" with some offcut meranti

http://www.boatdesign.net/forums/attachments/boat-building/69661d1335016663-manies-microcruiser-1000.jpg

Hi Manie,

Compared to a round birdsmouth mast a hollow square mast would be lighter for the same strenght and stiffness. Also a square mast is a lot easier to build and it's easier to make it taper in both wall thickness and outher dimensions. To make it taper would save a lot useless weight high up there as the bending moment in the mast goes down as the hight goes up. Aerodynamical round and square are almost equal for the same dimensions. But as a square mast can be build in a bit smaller "diameter" for the same strength it would give you better aerodynamics compared to round. This aerodynamic advantage would be increased if a straight birdsmouth mast is compared to a taper square mast as the latter is easier to build taper and if because of the build difficulty taper has been skipped on the birdsmouth.

Some quotes and links for info... - - Click on http://www.boatdesign.net/forums/images/buttons/viewpost.gif in the quotes if you want to go to that thread & post.

The only reason to install a square or rectangular section mast is to get some added strength through engineering. Square sticks are stronger then round in the same dimensions, meaning you can down size the square spar a bit, save weight and have the strength you need for the design's requirements.

Actually a round, hollow mast, regardless of build method will be weaker then a square section of the same diameter and wall thickness. Ditto oval and rectangular sections. The corners of the square and rectangle section masts are farther from the center of gyration, making them more effective at resisting loading with the same wall thickness. Also rectangular sections aren't as bad a leading edge in regard to penetration and disturbance as it would seem. This is well proven.Michael Storer Boat Design - Birdsmouth masts (http://www.storerboatplans.com/Faq/Birdsmouthmast.html):
----------------------------------------------------

While the birdsmouth mast is an elegant solution for a round mast it is not the lightest mast for a given stiffness. We have found we can actually produce much lighter masts using rectangular box sections (I always wondered why Francis Herreshoff used rectangular masts on his racing design). It is also possible for the masts to be built with much thinner walls than previously though this adds some additional labour and materials.Michael Storer Boat Design - Goat Island Skiff - Rig and rigging details for efficient lug sails (http://www.storerboatplans.com/GIS/GISRigging.html):
---------------------------------------------------------------------------------------------------

The main requirement for the lug spars is that the mast be relatively stiff but the yard and boom be flexible.

With the rig set up this way the boat will have the gust response of a modern rig as the yard and boom bend and allow the sail to twist. That's why such a light boat can carry a large sail but still be easy to handle in brisk conditions.69796
- - click pic to enlarge

Square hollow mast, don't make the outside round like this one (http://morocz.com/BoatBuilding/SchoonerBuild9.htm).

Material taken from the corners will cost you strenght and stiffness, so limit the corner rounding to the minimum which is required for wrapping with glass and/or carbon and/or kevlar, whatever is best and/or affordable, I don't know that. Have my doubts about plywood here, maybe others can say more about that.

Much more info on this topic if you dig into BoatDesign.net and on other fora as well.

Link (http://www.woodworkforums.com/f169/hollow-square-section-masts-81675/) - - Link (http://forum.woodenboat.com/showthread.php?71168-Unstayed-mast-design)

Good luck !
Angel

04-25-2012, 06:51 PM

Very informative Angelique. Points to you!

The only counterpoint I might throw in would be the way the yards would ride on a square section mast. Most likely, a padded and rounded (radiused corners) mast would not effect the yards in any way. I'm working a design with this kind of rig and the squared-section mast bothers my sense of harmony when it comes to it's interactions between the spars. A rounded top section where the yard rides could be done with no loss of strength. My fear though is a stress(compression by the yard) on the corner of the mast might cause crushing with failure of the surface finish, water ingress, etc, etc,

Perhaps others could expand on these thoughts?

Angélique

04-26-2012, 10:40 AM

The only counterpoint I might throw in would be the way the yards would ride on a square section mast. Most likely, a padded and rounded (radiused corners) mast would not effect the yards in any way. I'm working a design with this kind of rig and the squared-section mast bothers my sense of harmony when it comes to it's interactions between the spars. A rounded top section where the yard rides could be done with no loss of strength. My fear though is a stress (compression by the yard) on the corner of the mast might cause crushing with failure of the surface finish, water ingress, etc, etc,

These are the options and their consequences for compressive contact stress between mast and yard....

Round mast + round yard:
Contact area for resting and bumping is just a point so compressive stress is high.

Square mast + round yard: - (yard contact on a slightly radiused mast corner)
Contact area for resting and bumping is a just a point but on a smaller radius then on a round mast so compressive stress is even higher then in situation #1.

Round mast + square yard:
Contact area for resting and bumping is a line as long as the yard's width* so compressive stress is lower then in situation #1 & #2.

Square mast + square yard: - (yard contact on a slightly radiused mast corner)
Contact area for resting and bumping is a line as long as the yard's width* but on a smaller radius then on a round mast so compressive stress is higher then in situation #3 but much lower then in situation #1 & #2.

* width meant as outher thickness of the yard

#3 gives the lowest compressive contact stress and #4 comes near that and gives the best mast strenght and as the top end of the mast needs less strength LP's sugestion to round the mast above the lowest reef point of the yard might be a good idea.

But as weight and aerodynamics are more important at the top end of the mast then on the bottom and have a big impact on the boat's behavior and sailing capabilities I would adapt scantlings to that and taper the mast in both wall thickness and outher dimensions which means calculate the mast over whole length and not just the bottom.

To reduce compressive contact stress between mast and yard it might be sufficient to give the mast corners above the yard's lowest reef point some more radius which would get us almost at point #3 for the contact stress .

Maybe the planks can be processed on Dries' CNC router to taper them in width and in thickness and also make the scarves for the planks length joints ? That would allow for a quick mast build . . :)

Good luck !
Angel

P.S. - Let's not forget Fanie (http://www.boatdesign.net/forums/boat-building/manies-microcruiser-27869-23.html#post495575) already spotted a nice tree for the mast (http://www.boatdesign.net/forums/attachments/boat-building/62621d1319108806-manies-microcruiser-monkey-ass_weird-animal-pictures.jpg), too bad that damn monkey got in front of it . . . :eek:

Manie B

04-26-2012, 02:46 PM

Hi folks - thanks for the info.

It will be a round birdsmouth mast and it will be tapered.
Boom and yard will be rectangular, both tapered to the ends.

The reason why I am going this way is the popularity of round tapered masts as FREESTANDING. I have read of the good results that was achieved with square or rectangular masts that were supported with stays, but I am more comfortable with a round "stick" than a square "stick" freestanding.
The birdsmouth also has a greater contact area for glue than butt jointed.

We are working on much more data and I will publish all the figures and calculations when it all comes together.

The reason for the delay has been - what wood ??
The good news is Dries has located a local supplier that has SPRUCE at a good price. So know that we know we can get Spruce we can go ahead with final calculations.

So all round its good news and the project is back on track.
I have started experimenting with a jig to do the tapers and the results were excellent. Will post pics of that when it gets off the ground.

Manie B

04-27-2012, 03:11 AM

Just a bit more info on what made me think in this direction

However, a ‘square’ section with rounded corners such as this would be unsuitable for any rig which uses mast hoops or parrel beads or a lug rig where the spar turns against the mast.

There have been several configurations used to increase the gluing areas across the width of built staves.
And several configurations which attempt to reduce wastage and at the same time produce large gluing surfaces.
Unfortunately while they will produce superb, strong masts they call for increasingly complex carpentry.
The ‘Birdsmouth’ technique developed by Noble-Masts in Bristol UK is perhaps one of the most successful of these techniques.

http://www.diy-wood-boat.com/Mast.html

There are several reasons why soft woods are the chosen type of timber used in the making of masts and spars.
The first and most obvious is that so any soft wood trees grow exceedingly tall and straight.
And because they have grown so tall and straight they have developed the ‘elasticity’ to withstand all that the elements can throw at them.
Soft woods are also more likely to be lighter in weight.
Sitka Spruce (Silver, Tideland or Menzies Spruce) has long been the top choice for mast builders.

here is a nice discussion on stiffness
http://www.woodworkforums.com/f169/gis-spars-109530/

To me a birdsmouth also looks "knitted" together, an interlocking unit that supports each other - if that makes sense ;)
not just a couple of planks that were thrown together.
I also see the "other" attempts as justification to make the job easier, quicker, faster, and ultimately lazier.

One thing that I have learned the hard way, easy is not always better. Rather keep on slogging away, its worth it in the end.

here are some pics I got off the interenet
you can see where I am going with my "taper" jig, first cut in the "V" groove, turn around and then taper the opposite side. My side guides will be 50x50 steel tubing.

always exiting, always something on the go :)