the boatbuilding journey

I think Cats are a proven design now too, after fifty years of them being built. they sure have come a long way since Piver and in mho the ugly Gemini's. Cats are fast but must point further away from the wind, mono's are slow but closer to the wind. they arrive around the same time at a given point...although, i know of at least two fast racer/cruising cats that will point into the wind as good as any trimaran. and probably as good as a monohull.
and i like speed when sailing...thats just a preference...
loved sailing the hobie cat. that was a joy to sail. plus there is less rolling motion which *might* eliminate seasickness for the cat crew over a mono.
i agree with PDW on the k.i.s.s. principle. no question the more complex, the longer to build-the more money and the problems of breakdowns etc...
but as i always repeat ad nauseum--boats are always a tradeoff..no perfect designs exists other than in bizarro world...

Catbuilder--is your cat potentially beachable?

 

Actually, multihulls are considered to be among the first boats ever built, dating back to ancient times when the Pacific Islanders used them. This was several thousand years ago. They aren't new. They are extremely ancient. Obviously there are no issues with them or I wouldn't be on my 2nd one. I'm not sure pdw meant it that way. What I'm jealous of about his build is simplicity.
With a 2' draft, retractable rudders and daggerboards, coupled with a set of retractable outboards, I'm very beachable.

 

What I have found out so far.. making decisions is the hard part. There's just too many possible ways to do something and knowing all the pros and cons for each of them is allmost impossible. Ones the decisions is made it's just some dough and hard labour to get it done. Now I have maybe 25% done, 50% figured out how to and rest 25% on the drawing board so to say.
The drive train is the last of the "figured out" tasks. I have to change another gearbox (got a quote today 2k€ swapping to the old one) to have a PTO for the generator. CPP comes from Nogva, it will hit hard, about 5k€ (not yet ordered but soon when I have the specs of the new gearbox)...
Dilemmas:
Galley.. Diesel or electric? no propane for me..
Electrics.. size of battery bank, voltage etc..
Decisions..

 

Teddy--yea this seems to be a recurring theme- its interesting that we are all having pretty much the same trouble...i know its trite- but im glad that im not alone--i was starting to think i had real issues with the decision process..(maybe i still do?) but at least it seems like a consolation to see now that others going down the "build-aboat-from-scratch-and retire-to-the-carribean" dream- are having similar issues..your input was appreciated. I apologize in advance for this -but im not sure what your building? ..is it a sail or powerboat?
I used propane for my galley and found it safe...had the tanks stored on deck ran the lines through into the house. but everyone has thier own way.
battery bank size is hard. I thought of using l.e.d. lights for the whole boat except of course the running lights. yea..DECISIONS..this is what is coming to light on the builds..mine incuded..once my frames are set-up--ill have won half the battle...1.5 months to go..
did you say a controllable ptich system??..my my arent we fancy!!(lucky guy!)
i envy you grrrrrrr....

 

No worries i wasnt criticizing pdw just adding that they seem to be proven as well...my build might even be more simple..there is no brightwork..the wheelhouse will be plywood with an overlay of knotty pine(naughty pine!)
the hull will only need basically to be welded like a box..since its flat bottomed. the only complicated part(there are exceptions to every rule sadly) is propulsion..hydraulic or steam or electric--but it MUST be one of those...i dont want a big diesel consuming a months wages over a weekend of running. again- another "non-negotiable"

Beachable--now see- this is a great idea!..my concept of a boat was that one of the - "non-negotiables" was the ability to beach her--with twins and two full length keels on my tug its possible- actually i decided(another of those freakin tough ones) was to build a second small barge to push my accomadations around--this is where the simplicity comes in--
1. the barge has no motor and can be anchored and thus can be built using cheap ply and epoxy..it wont last a long time but it will give me up to ten years while i build a bigger version of it in better materials..
2. the barge can be anchored with the tug thus eliminating mooring fees in my area.
3. the barge has huge amounts of space and accomadations can be the size of an apt! plus it can be made with common 120 volt systems and use oridinary materials ..making it very inexpensive to build...realtive to what a yacht interior would be...
4, the tug is then used as a tender vessel, and i can move my house to warmer climes in the winter- or if i dont like the company nearby--im off to a secluded cove..all the while having fun towing her.
5. i dont have to pay for a 45 ft slip fee- only 25 -27 ft fees. if staying over at a marina...to me this is simpler than building in accomodations on a larger yacht. the tug will look crappy--true---but GOOD! want it to have that well used commercial look to it..with a plywood panel in the house and cheap equipment--i can say its "commercial" and no one will care or notice--not that it matters, my opinions of what others think -it doesnt; but i can keep my costs down by using the "Brent Swain" method of scavenging used parts etc...keeping it simple allows me to do this --see my props for an idea--those would be 1300.00 new..i paid 500.00 for the pair. i have a shaft too--aquamet 19 72 inches x 1.5 with coupling and nuts keyed the works..for 425.00! still need one more--but its a start...simple simple simple is the way!

 

Well.. some could say I was unable to decide so it's a motorsailor
What comes to my galley "fuel" intention are the looongest possible time spend in remote locations out of the reach of refueling possibilities so diesel tanks for some 1.5t of fuel and running a gennie for scuba compressor watermaker and the electric galley. Somekind of a diesel stove . Maybe biggest possible windmil hoisted up the mizzen while anchored.. let's see. Anyway looking to have two months or more away at once..

 

I didn't mean it that way, I've no issues with catamarans working as boats. You pick your tradeoffs and go from there. One of my team used to be a catamaran guy and he'd owned a lot of monohulls so I'm familiar with all the arguments. You get lots of time to argue on voyages taking 2-3 months straight sea time

My preference is just that, preference. The comment was aimed at my choosing a design where it was designed by a person who then built 5 in his own yard, more than 150 had been built since, mainly by amateurs, some had been taken on a circumnavigation, at least 3 documented cases of quite severe impacts on rocks etc without hull breaches, etc.

My hull draws 4' and can be beached as well, as long as you have some props to keep the hull upright. The keel shoe is 7.5m of 200x40 flat bar well supported by floors and plate so I'm not the least worried about damaging it.

PDW

 

Agree completely. What works for me is not to get frozen on a decision point. There's usually something else (generally mindless) you can be doing while you think about it. In my case it was angle grinding back all the welds, plenty of time for thinking there. Let another part of your brain pick away at the problem.

I've still got the final hookup of my steering gear to do. I've solved that one 4 different ways but what is the *best* way? Eventually I'll just do it when it comes to the top of the critical path and live with whatever tradeoffs ensue. If I really don't like it later, well hell, I built the boat, I can change anything I want if I'm prepared to spend the time/money.

Engines - I was going to rebuild a Yanmar. Cost of parts etc started pushing $5K. At that point I decided to just spend a lot more & buy a new engine with warranty and no issues.

I've all the timber etc I need for my fitout, been collecting it for years. Cooking will be LPG due to lack of decent alternatives. Refrigeration is a big unknown because that leads straight into energy storage (batteries) then recharging methods. I worked out that it was going to cost me around $5/hr to run my main engine so there's no way I want to do it just to recharge a battery bank. Easiest to skip a reefer frankly. I'm keeping my eye on catbuilder's progress with LiFePO4 batteries....

PDW

 

Just a point - hydraulic isn't a power source, it's a method of transferring power. You need to drive the hydraulic pump with something. There are losses involved and it can be quite noisy.

Forget electric power, it simply doesn't have the power density unless you're planning on going no further than your extension cord can reach. Look at catbuilder's threads on the subject. It will not work for you either.

Steam is interesting but how are you going to source the boiler, how are you going to feed it combustible material, what's your strategy for cleaning the firebox, where are you going to store the amount of wood/coal you'll need etc etc? Are you aware that there are very strict rules regarding boilers and their testing? These rules are mandatory and make total sense because a steam engine is a bomb waiting to happen. I think you'll find the bulk of gear needed for the HP you need will render it impractical.

Like it or not diesel is the best way to go.

PDW

 

yea-- i wish there was an easy way to run electric-although im reading a book right now called electric propulsion for boats by Charles Mythys.
who knows?

quite correct- diesel is the best way--theres no doubt that for ease of installation and ease of running this is the way to go-but its expensive. and for the price of your yanmar repair id have a used engine and a pair of hydraulics set up or two steam engines..(3200.00 delivered from india) diesel is nice..and i would really only trust a new one--even though i could not afford 15 000 for a good new one.

the real problem for me is the prop aperture in this hull.

If i use two props, its better- i can swing two good sized props under her. but if steam id need a 45 inch prop under her for one engine with a 3:1 reduction. this just is impossible- and a single diesel would need(for my purposes) a 32 incher.

this does not leave enough room for tip clearance. (assuming a good sized engine-enough for good bollard pull).
i guess Im not prepared or willing or even want two counter rotating engines even if i could afford them--by now you probably know i do not have financial resources many others do on here...what i am good at is ingenuity. hydraulics seem the most viable to me-

steam:
i have a boiler shell - its 1/2 inch thick pipe 30 inches long, i would add another 16-24 inches of shell to it -have the plate rolled etc ....@ 1/2 inch thick is overkill for a boiler.(i do know a little something about pressure vessels). the standard for the size boiler i need is 3/8th thick A70(?)pressure steel.

I have plans for the boiler and they really arent hard to make at all..I would use a 60 sq ft design- firetube type- with about 60 gallons of water- this allows for the boiler to not be fed often as they hold steam longer and need feed water less too than WTB's which are the safest and will not explode--the pipes burst first(at about 3000 psi!)...but i dont like watertubes because they need to be tended to more often.and more expensive to make. so a good scotch type would be the best option.
now going with steam means cleaning the tubes--quite true.

but thats very easy to do on a hft or vft. you would use a long wire brush about once a year...

my plan was/is(?) to get two tiny tech 10 hp steam engines and run off one boiler- easily done again. the costs of this is about 5000.00 complete with boiler built and engines shipped. the fuel can be anything--but the beauty of the hull i am building is its got a lot of area,-its a flat bottomed hull so weight is not as critical (think barge with a rockered bottom and fantail stern and dont forget model bow too!) under the deck and no accomodations so the engine room -under the decks, the bow etc, all can be filleed with wood. with a little planning for weight distribution and trim adjustment its easily done--of course the trip must be planned around the firewood, gathering [-loading etc...and a 1 hour long fire-up time.

in the event of a storms, when at anchor and needing a quick egress this is not the most practical propulsion...so nothing is perfect. but wood can be found anywhere here..its free fuel as i see it!

There is a company here that makes a type of log called an eco log- its basically compressed sawdust held together by the heat of compression which fuses the natural resins in the wood to form a very good peice of wood.
this wood burns three times hotter than a solid maple log (about 15 000 btu's per lb!) and lasts long, and they are cheap. also cordwood here is about 100.00 bucks a face chord which is about a days running maybe two, at half steam. as for boiler inspections--well again good ol' canada doesnt have any inspections...they must be code boilers in the states in some areas-but not here. I looked into that before i started my project. but boilers now are very safe. -have better steel -this was the big issue a hundred and twenty years ago before water tubes were invented- they didnt have uniform steel properties and were iron-so they werent as stable and blew. and did not have the safety valves either.

nowadays they are as safe as a home water heater which as you may or may not know some are rated to 300 lbs psi!! double what i would need for my boiler. as redundant safeguards there are two kick off valves -or steam release valves. one is set at five psi above the first which is set at 5 psi lower than the max operating pressure.
the boiler is quite safe if done well..and i could build one for about 900.00 using my present shell..so this makes steam very viable for me -although it has drawbacks--its warm in the winter but bloody hot in that engine room in the summer... but i really dislike the smell of diesel anyway...so fire smoke has its appeals.

its also possible to run hydraulics off a steam engine too...or again (DECISION DECISIONS, POSSIBILITIES) to have a genset off the steam engine to power ev motors..

another issue with steam--you have to preheat the water and add the water- this means you must tend to the boiler more often--feed it more etc. so it takes away from the nice steady cruise of a diesel engine..but im prepared to do this singlehanded...it means running down to the engine rm often-and gets complicated in a tight situation when u r running out of steam.

I have experience with steam AND I know the ins and outs--i worked for a guy who built steam engines so i am familiar with the systems and drawbacks etc..in fact after writing about it--it feel right to go with steam for me- and the last great advantage--they are, hp for hp- torque for torque more powerful than diesels- an 18 hp geared 3:1 would have over 600 ft lbs of torque!! needing a 55 inch wheel! AND probably pull a 6-71 backwards. in a towing battle...and not even be working it too hard.so a 200 hp steam engine? well thats off the charts! but its not going to go 9 knots as a diesel powered tug will on a tow.
the drawback- you travel at 5 knots --but you also tow at the same speed...

one other important thing about steam--you dont have to be a mechanic to maintain it, or operate it...there are no panels, no harnesses-electric and its really simple systems..just piping..all the parts are in the open so you know whats going wrong and they are built to last!

as you can see--its all tradeoffs.. steam really does appeal to me..

hydraulics- this is what i know about them thus far-

well they are the best option for a twin screw... yep--you use a diesel.
in my case, about 80 hp. this runs two pumps which in turn run two engines and flow back to two spool valves--instant reversing! (steam as well has instant reverse with stephenson links and other types, although some engine have dead spots in the reverse you need to be careful about).

anyway the now hot oil then flows back to a return line into either an oiler cooler or reservoir or both. this lets the engine run at constant rpms too...
the hydraulics ive got pegged are char-lynns 31 hp each at 720 rpms -allowing for two 22 x 22 props @ 1:1, 412 ft lbs of torque!

but my props are 22 x 19 so thats what they will use.
the advantages of this is of course- agility in maneuvering, due to the quick response of hydraulics. but there is risk of an oil line break which is NOT pleasant.

but also one engine drives two powerful engines.-essentially what is happening in this system is the hydraulics act as reduction gearing. spinning the actuators at 500-700 rpms in the same way a gearbox reduces mechanically, the diesel.

and there is loss too- about 30-40% but in reality its apparently not that much. I also could conceivably eliminate stuffing boxes as the hyd. engines could be bolted right through the hull..or they could be set in a pipe with a gasket. the coupling of course would be inside the pipe. a simple double u-joint would solve coupling issues too...but they(u-joints) would be submersed in water--i have yet to solve that.

it would be a simple thing to have stuffing boxes....

so thats my take on what my options are--i wont be using a single diesel- unless to power two hydraulics motors...unless there is some other options ive not heard about..like safe nuclear power or, some mind bending way to charge batteries faster than they drain...

electrics-

i respectfully disagree on electric being unviable.
they way to do it would be again a diesel. and again only because i would need two props from one engine--how i would do it is this-- have two 48 volt motor - es 70 b's from D& D motors 6 inch dia x 15 inches long..weight about 90 lbs each. shunt wound. 70 ft lbs at 1361 rpms. create two battery banks. one for each engine--this also helps ballast the boat too.
these are connected to high output military alternators--or either 24 volt windmill motors -one for each two batts - or heavy duty 48 volt types which r very rare or you can have them built at a price! anyway you want high amps so you cna direclty run the diesel to run the electrics. you are charging the batts as you run. but the trick is to have more power going in of course than is consumed. so as long as the engine can turn 8 alternators, or four heavy duty ones--you should keep up with the battery drain. of course -you could just charge the banks and run two hours off them then stop recharge nd go on again...
this system is also redundant. but for turning one engine in two props it could work-depending on the set-up and it would take some tinkering...threy are using electric in boats now..hybrids too...



so what engine/hp have you decided on PdW?..i envy that you can afford to buy new...someitmes i think a single diesel would just make it all so simple ...or even a single steam engine...

 

If you're looking at steam,have you looked into wood pellets??

IIRC they're about 8500 BTU per pound...you'd have to compare the prices but I think the only thing cheaper per million BTU is coal.

 

westvanhan--hello from Prince Rupert! im here on vacation till the ground unfreezes in ontario... i believe oil has more btu's per weight- ......followed by coal...wood is last..but theres lots of it..i think its 5000-7000 btu's per lb for hardwood-oil fired boilers require complicated systems such as an oil nozzle and a blower.

i thought about wood pellets , but if im not mistaken i need a special stove for that..i know in ontario it works out to be about the same price to heat with wood pellets as it does cordwood-the pellets have the advantage of being lighter. but the pellet stoves ive seen are 2000.00!!
these eco-logs seem to be the answer...cdn tire sells them for 20 lbs i think its like 7 bucks or something but they burn hotter and last as long as hardwood. ill burn wooden pallets if i go with steam i can get them for free just about anywhere...
btw have you seen the "MASTER" steam tug--wow its so beautiful...should be in vancouver area...?

 

OK, on a quick scan over that I see you're aware of most of the issues with steam. I used to hang out with a bunch of live steam locomotive types (friend of mine has built a Shay) so I know a little about the issues.

I like steam engines myself, there's a well preserved gentleman's steam launch in Hobart. Often thought of building an engine of my own to play with but it has to be at least 15HP. I don't have the time.

With electric, I thought you meant pure electric drive. Diesel-electric (or steam-electric) is a different animal, quite viable if you can afford the weight & space. Catbuilder couldn't because catamarans are space limited and weight sensitive. I quite like the idea myself for a variety of reasons and one of my engineer friends & myself kicked around fitting it to my boat.

Consider getting a diesel gen set, one of the bigger ones with a 3 phase 4 pole alternator. Put a 7.5HP 3 phase motor on each prop and - provided the props are LH & RH - you've easily got your counter rotation, speed control via decent VFD's and easy reverse. You can water cool the gen set straight from the lake as you're in fresh water.

I bought a Bukh DV36 with a 3:1 reduction g/box. Cost a ton of money but as I'd been offered some consulting work on data from oceanographic instruments, something I would have done for free because it's interesting to me, I went ahead & bought it. Problem with spending $5K on the Yanmar was, that might not have been the end of it, the cost was pretty much all parts apart from an injector/head overhaul, and when finished I still had a 30+ year old engine.

I've got 2 quite functional Lister air cooled marine diesel engines with 3:1 reduction boxes in my shed. There are a lot of engines about the place if you start looking well in advance of needing one.

PDW

 

Hey Tug-enjoying the storms?

Yes,I've been on Master-I volunteered to help do maintenance,and then went out on a run. Simply awesome.
Every summer there's a great wooden boat show,if I go this year I'll take pix for ya.

Anyways what I meant was that pellets were best among alternatives to diesel,it seemed you were trying to get away from diesel.
I had a birch firewood business in high school..made a bloody fortune so I know a bit about birch.

Also look into space..looked it up for you quick:
-pellets at 8500 BTU per lb so 17 million per ton,40 pounds is one cubic foot,so you're looking at 50 cubic feet per ton.
So 340,000 BTU per cubic foot.

-hardwood cordwood lets say birch..is 3200 pounds per cord to get 20 million BTU ( I looked it up). A cord is 128 cubic feet.
So 156,000 BTU per cubic foot.
But in reality with the gaps in stacking you'd lose 15% or so of that.

With those eco logs you're looking $350 a ton,but i don't know BTU

So you have to figure the costs of the materials vs the cost of building a much larger boat to hold more wood.

edit> also consider the efficiency of pellet stoves at ~82% vs wood stoves at usually a lot less.

 

I like your idea- how big a genset would be needed for that way of doing it??
im not familiar with ac current in an ev application --how would this be set up? what would be needed to set it up??..three phase means some expensive controllers? any info on that i'd be interesting in learning more for sure..thanks...
maybe-is there way to convert tthe 3 phase ac -to dc power? dc engines are powerful and cheap, but of course there r no good sized alternators and they need high amps..like around 500 amps to get good performance--its these reasons--the complexity -that i would prefer hydraulics... or steam..

WOW--i think lister is the best diesel there is!--powerful slow turning- they last forever usually...

there was an ha3 for sale around here--i could have almost taken it away. but the engine was seized solid. the girl had no idea about engines and her father had passed.she didnt know to put oil into the cylinders...it was in great shape other than it was seized..i would have used that in my boat without hesitation--it even had a 3:1 gearbox - was a lister -blackstone.
I figured it would be too hard to unsieze it and a whole lot of headaches...
im wondering now---what youve got and what shipping would be to Canada if one were for sale!!?...just thinking aloud.
15 hp is quite large...there is a prop here that was for a 17 hp triple on a 60 ft fishing boat and it was huge like 4 ft diameter and probably 60 inch pitch..goes to show how big a wheel they can turn..15-20 hp in my tug makes it a monster...but if i can use two 10's ill have quite a lot of power..but it wont make the best use of it because again the aperture wont take a huge prop...i could get away with 2) 5 hp steam engines but then the torque is low and again - 2:1 give me a 40 inch prop..
and 1:1 has low torque for my needs...

Bukh is a great engine too- i looked at one that was used...but it was 20 hp only...wanted 3000.00 used. so i passed.

im guessing you'll use about a 18 inch or more prop at 3:1?--you made a wise choice in my opinion.. used to love watching yt vids of the canal boats with the old listers. the ha3 36 hp @ 1800 rpms i think...what a great engine...too beefy for a sailboat perhaps?
just listen to the raw power of this engine...!! an ha3 lister.

http://www.youtube.com/watch?v=fYDBhjy0OAg