Ok, Now What...? [Archive] - Boat Design Forums

Willallison

07-18-2002, 02:28 AM

OK, don't laugh (too hard). Here is my design for O-1. Sorry about the quality of the graphics. I don't have any good drawing programs at home.

Participation Rule #1
"Ye shall note laugh at another's drawings until ye hath posted something superior!"
:D

Duck - here come the darts!
Lets start up front shall we.....

For O-1, I prefer a relatively plumb stem. It increases waterline length for better rough water performance and maximises interior space.

I gather that you have incorporated a drop-leaf table, just aft of the helm? This would interfere with opening the fridge (which I am also assuming is located just aft of the helm). Your boat is capable of sleeping 3 (4 if the back of the 'lounge' flips up), but only provides seated dining for one - 2 at the most.

True, locating the loo in the salon allows for a lower overall height, but it restricts visibility aft. (I know Tom will have something to say about this...) If this becomes a necessary layout VCG reasons, then I would like a second helm located in the cockpit, or a hatch over the driver, allowing him (what! You guys let your wives drive the boat!?!;) ) ok her to poke their head out if necessary.

I'd also like a hanging locker for wet weather gear etc.

Oops - run out of sharp darts.......back soon

Portager

07-18-2002, 03:24 AM

OK, try this. I changed the bench seat to a booth. I like this better because you don't need a drop leaf table that is always going to be in the way and the passenger can look out the window while underway.

The skylight might be tooo big :D but I'm too tired to change it.

Cheers;
Mike Schooley

tom28571

07-18-2002, 09:54 AM

Got my supply of darts ready.

1. There is no comfortable seat for the mate to have a view forward. Your first layour seems to use Devlin's idea is the mate sitting on the port counter with feet resting on the port bunk. One of Sam's ideas that my mate and I don't like.

2. When the table is down there is no open passage. This will lead to much strife.

3. I also would extend the waterline to a nearly plumb bow. Besides, it suits a classic design better.

4. With as much window area as this, there is no need for a skylight and it restricts space on the cabintop for a dingy or solar panel or whatever. In southere climes, it would be too hot.

5. No hanging locker.

6. No drawer space for gear and clothing.

7. No anchor well forward.

8. Not enough light in sleeping cabin.

9. At this length, the boat should use all legal beam.

10. How wide are the side decks and is it possible to do mooring and anchoring work from inside the forecabin? Safe side decks will greatly restrict room in the pilothouse and need to be taken into account when laying out the interior.

Next dart chunker, step up.

Portager

07-18-2002, 11:32 AM

Originally posted by tom28571
1. There is no comfortable seat for the mate to have a view forward. Your first layour seems to use Devlin's idea is the mate sitting on the port counter with feet resting on the port bunk. One of Sam's ideas that my mate and I don't like.

The second revision changed the port bunk to a booth with seats facing fore and aft.

2. When the table is down there is no open passage. This will lead to much strife.

See comment above.

3. I also would extend the waterline to a nearly plumb bow. Besides, it suits a classic design better.

OK, rev 3 has a nearly plumb bow.

4. With as much window area as this, there is no need for a skylight and it restricts space on the cabintop for a dingy or solar panel or whatever. In southere climes, it would be too hot.

The skylight is optional, to appease the soft top crowd. It is much smaller in rev 3.

5. No hanging locker.

The hanging locker was added in rev 3. It is to starboard just forward on the pilothouse entrance. The floor of the locker is raised and drains into the cockpit. The space below would be used for electrical/mechanical equipment.

6. No drawer space for gear and clothing.

There would be drawers/cabinets below the counters and under all the seats.

7. No anchor well forward.

The anchor well is in the bow. The hatch was added in rev 3.

8. Not enough light in sleeping cabin.

Rev 2 shows a hatch/skylight in the forward compartment.

9. At this length, the boat should use all legal beam.

I limited the beam to 2.5 m = 8.2' for international trailerability.

10. How wide are the side decks and is it possible to do mooring and anchoring work from inside the fore cabin? Safe side decks will greatly restrict room in the pilothouse and need to be taken into account when laying out the interior.

They are 1 foot wide most of the way. Same as Devlin's Surf Scoter 25. Handholds would be on the pilothouse roof but I was too lazy to draw them.

I have also rotated the head to face aft. You should now be able to sit and close the door. The Admirable likes that :). The entire floor of the head drains into the shower drain so the shower door doesn't need to be water tight. The shower door just maintains a dry area where you can have towel racks and set you glasses while in the shower.

I have shown fore and aft fuel tanks in rev 3. There hold 67 gallons each or 400 lbs. I'm thinking this location is too far aft for good CG management. The only alternative I see so far is to raise the pilothouse to get enough room for the fuel tanks under the floor. Any comments?

I currently have the refer/freezer shown as 3'X3'. I think this is overkill but the engineer in me likes the optimum square dimensions :).

Cheers;
Mike Schooley

Portager

07-18-2002, 05:43 PM

I was working on the Phantom Boat today and I paid special attention to the side decks. They are about 8" at their widest and much narrower in localized areas. In addition there are no handrails and nothing to hold on to at all when the top is down. These always seamed marginally adequate to me, so I think the 12" should be good.

I have a collection of darts that I recently acquired and I am getting anxious to use them.:D When are you guys going to post something?;)

Cheers;
Mike Schooley

Willallison

07-18-2002, 07:23 PM

Definitely better Mike.
How do you prevent water from entering the main cabin from the cockpit? If there is a step down to inside, then the height of the rear door is already restricted, so lifting the bottom of the door up will only compound the problem......

Ok, time to put up or shut up so - based on the lines that I have drawn and the napkin sketch which I have previously posted, here is a section to give a better idea of my idea for O-1.
Note that the section lines (pink) are not to scale and the rest is only rough...

Preliminary specs are as follows:

Transom deadrise 12.5 degrees
Midship 23 degrees
@ stn#2 54 degrees
Displacement 1385 kg
Draft 0.25m
LWL 7.51m
Beam 2.5m
BWL 2.1m
LCB 63.2%

As previously stated, I like a plumb bow - longer LWL, more interior volume - and I think they look cool!
Anchor lock up front (I'd have a remote operation anchor winch too) I haven't drawn it but I'd also have a bowsprit with the anchor permanantly mounted on a self launcher. This also aids disemarking from the bow. I rather like the idea of a fold down ladder from under the sprit too, so you can beach the bow and step off....
V berths are 2 metres long with storage under. An infill creates a large double. A hatch up front provides easy access to the bow / anchor (not drawn). Removal of the centre section of cushions means you wont walk all over them with wet feet. Headroom in the fwd cabin is 2m.
Stbd side, aft of the berth is the head. Headroom here is slightly restricted (about 1.7m) but adequate. The shower is integral.
Port side, opposite the loo - In the drawing I have shown a tunnel berth with the aft section running back under the galley, creating 3 permanent berths. There would be storage under this berth. An alternative would be to replace it with a storage cabinet - a hanging locker and draws.
Up into the cockpit, a double helm seat is located stbd, the back of which flips forward to create the aft facing 1/2 of the dinette. The table drops to create another berth. The fridge is located beneath the helm seat, a 'wet' locker in the back support of the fwd facing dinette seat and stowage in its base and in the raised floor under the table. The raised floor at the helm in the hardtop model, allows the driver to stand up and poke his head out through a hatch above. A second, larger sliding hatch or canvas sunroof could be incorporated for those who desire it.
On the port side is another fwd facing seat. this flips fwd to create additional bench space for the galley which is located immediately aft of it. The gas water heater is located under the counter at the rear of the galley, with its 'chimney' running up through the radar arch support. The gas bottle I have located in its own externally vented locker, under the aft bench seat.
Twin transom doors provide access to the boarding platform, which surrounds the outboard, giving excellent access for servicing etc. The centre section of the platform lifts with the motor when it is tilted.
As the entire cockpit is raised, it is self draining. It also provides an extraordinary amount of under-floor storage and allows the location of fuel and water tanks at the LCB so they don't effect trim.
Side decks are 250mm wide. providing a reasonable compromise between safe bow access and interior space.

Now, I'll just duck while you guys start chucking!!:D

Willallison

07-18-2002, 07:38 PM

more images of my O-1 hull:

Willallison

07-18-2002, 07:41 PM

and another:

Willallison

07-18-2002, 07:42 PM

now I'm having fun!

Willallison

07-18-2002, 07:45 PM

and last but not least:

Portager

07-18-2002, 08:30 PM

Will;

Not bad, but:

Although there are obvious rear visibility benefits of putting the head forward and below the penalty is that everything aft must be raised for visibility. I am concerned about stability and the A/B ratio of such a light weight craft. You have a height to beam ratio of 1.2. This would be easier to accommodate if the engine CG were lower, but the outboard aggravates the CG problem. However, the soft top helps somewhat. I'll keep my fingers crossed.

For comparison, my height to beam ratio is 0.93, although I think it will be higher in rev 4;).

It looks like you have a tunnel berth on the port side (its hard to read). How does this work with the forward facing seat above? Where do you put your legs & feet?

It looks like your LWL should be 8 m and LOA is 9 m. You could increase length to 9.75 m which would make more room in the cockpit.

Originally posted by Willallison
How do you prevent water from entering the main cabin from the cockpit? If there is a step down to inside, then the height of the rear door is already restricted, so lifting the bottom of the door up will only compound the problem......

You have a good point. Look for rev 4 to correct this design flaw later tonight.

Cheers;
Mike Schooley

Nomad

07-18-2002, 09:07 PM

Please keep your hands and feet inside the ride and prepare for the darts...................Wel I only really have one that I did not see covered. Why cant the beam be 8'6''?? :D ;) Every inch adds up! :)
I think I'll have to sit on the sideline with Trouty for a while unless you guys need to call in the second string................

Willallison

07-18-2002, 09:27 PM

Why cant the beam be 8'6''?? Every inch adds up!
O-1 is a "world boat". Max beam in Oz (and a number of other countries who have converted to the modern world - oops! I mean metric system:p ) is 2.5m or 8'2 1/2".

You have a height to beam ratio of 1.2. This would be easier to accommodate if the engine CG were lower, but the outboard aggravates the CG problem. However, the soft top helps somewhat. I'll keep my fingers crossed.

My searay has the floor raised to the point where you can comfortably fit the engine (and an arthwartships double berth) under the cockpit floor. I've not found it to be unduly top heavy. The floor in O-1 would be lower than in my boat, so I don't think it would be a problem and this should also compensate for the higher CG of the outboard.
It looks like you have a tunnel berth on the port side (its hard to read). How does this work with the forward facing seat above? Where do you put your legs & feet?

I designed this berth for very short people!!:D :D
Actually, I have a step up to the companion seat. This should provide plenty of height for legs, as the berth would be located quite low down
It looks like your LWL should be 8 m and LOA is 9 m. You could increase length to 9.75 m which would make more room in the cockpit.

All the specs are taken from my CAD model. The sketch is just that - not terribly accurate. I agree, it might be nice to add another 0.5 to 1m to the length in order to increase the amount of room available in the cockpit.

duluthboats

07-18-2002, 10:16 PM

Will, Yours works for me. EXCEPT! Can we change that shear line, just reverse it, make it concave.

Mike, I really like yours. EXCEPT! Thats a lot of boat can we make it go.

Gary

Willallison

07-18-2002, 10:35 PM

Gary - I'll have a play with the sheerline, but I think the reverse sheer works best here. A more 'traditional' sheer would result in the cabin sides appearing higher - the reverse sheer and the ....the...... what do you call that thing...the sort of chine thing 1/2 way down the hull sides, where there is an abrupt change in angle.....(is it a knuckle?) anyway that thing and the reverse sheer help to disguise the height.

Willallison

07-18-2002, 10:52 PM

Mike,
A thought about your cabin entry. You could incorporate a hatch in the cabin roof, similar to the layout used on many snail boats (oops - that must surelly be a typo;)
But don't be thinking I'm pulling out one dart, without replacing it with another!
I haven't yet come up with a successful means of enclosing part or all of your cockpit. Even if just with a canvas roof extension, it's nice to have a bit of shelter in the cockpit. Side and/or aft curtains can then be added for those who want them.

Willallison

07-18-2002, 11:57 PM

Gary, Tell a lie - did a quick sketch and the boat looks quite good with a 'concave' sheer. It gives the boat a more 'traditional' appearance - but I know you old guys like that!:D

Mike, how about this for a means of allowing a cockpit overhang.
A radar arch of sorts would allow the installation of a small screen so a cockpit helmsman could see over the cabin roof in all conditions. It would also support a canvas roof for part or all of the cockpit.

Portager

07-19-2002, 12:54 AM

I figured the fix for the fuel tank location and the door height was to raise the roof of the pilothouse or at least part of it.

To keep the CG down I decided to move the head and galley forward. This allows them to be wider since they don't have to be within the side decks.

I copied Will's flip back helm seat and added a second booth. I also copies Will's wet locker behind the seat backrest.

I like the new arrangement, but I'm not happy with the looks yet.

Originally posted by duluthboats
Mike, I really like yours. EXCEPT! Thats a lot of boat can we make it go.

It's the same beam as Wills and only about 2 feet longer. It shouldn't be much heavier. Of course I do need to add an engine. I plan an arrangement like Will's but I just can't bring myself to draw an outboard. eek:

Cheers;
Mike Schooley:

Willallison

07-19-2002, 01:05 AM

I like the new arrangement, but I'm not happy with the looks yet.

Argh! Sorry Mike - but that's damned UGLY!!:eek: :D

I prefer the galley upstairs - more ventilation, better view, closer to both dinette and cockpit, free's up space downstairs for storage.

It's the same beam as Wills and only about 2 feet longer. It shouldn't be much heavier. Of course I do need to add an engine. I plan an arrangement like Will's but I just can't bring myself to draw an outboard. eek:

I wouldn't have thought that your 1st one would be any heavier than mine - apart from the length. If anything it would be lighter as it isn't as tall....

Portager

07-19-2002, 10:50 AM

Originally posted by Willallison

Argh! Sorry Mike - but that's damned UGLY!!:eek: :D

You hurt my feelings:(.

I was soooo insulted I stayed up all night redesigning, NOT. Well I did have an idea for improving the looks. Check this out. I reversed the galley/head and the pilothouse. I had to add a "dog house" to allow a full height door. I have shown stairs instead of ladders because the admirable and my dogs prefer stairs, but this is a builder preference. There is room under the pilothouse for large fuel and water tanks close to the lateral CG and a small fuel tank can be provided under the cockpit (if necessary) to correct trim.

I also increased the height of the forward deck. It improves the looks and provides 5' of freeboard.

I prefer the galley upstairs - more ventilation, better view, closer to both dinette and cockpit, free's up space downstairs for storage.

With the galley aft, I can accommodate large window to provide plenty of light and the distance from the galley to the dinette is only two steps up.

Cheers;
Mike Schooley

Portager

07-22-2002, 01:39 AM

Here is my latest version. LOA is 32', beam 8' 2", height overall is 10', freeboard is 5', headroom in the galley, head and pilothouse is 6' 4". Head room in the forward cabin is 5' 4".

I raised the pilothouse seats so that you can see out the window. The forward seats on both sides would have reversible backrests to face forward during transit and face aft to form booths with seating for 4. The booths will convert to bunks so it will sleep up to 4.

I lowered the galley and head area to reduce the CG and to provide better visibility from the pilothouse.

Wet lockers are provided at the forward end of the cockpit on either side of the door.

Access to the bow would be through the hatch in the foredeck or over the roof of the galley/head and down around the pilothouse. A ladder would lead from the cockpit to the room of the gallery/head. The side decks beside the pilothouse are 10" at the rear and taper to 6" at the front of the pilothouse.

So tell me what you think. I can take it.

Cheers;
Mike Schooley

Willallison

07-22-2002, 06:53 PM

Well, Mike I would have to say that your 'raised pilothouse mini-express trawler' is a breath of fresh air. Something different - inspirational even!:D
Alas, I still have a few darts in my box so.......
I'm concerned that at 9.75m (32ft) we may be getting a little on the large side to meet all our weight / performance guidelines. LWL for your boat looks like being about 30ft. And of course (even though you can't bring yourself to draw it!) that there will also be an outboard sticking out back (and probably a boarding platform) so the LOA will be closer to 10.5m. We could always lop 1/2 to 3/4 of a metre off the cockpit, I suppose....

Then there is the relationship between the living area(s) and the cockpit. Head and galley access will of course be excellent (no trapsing through the boat with wet, sandy feet to grab a drink or take a pee...), but conversation and sightlines between those in the cockpit and those sitting inside will be difficult. The trick with a small boat is to make it feel big - that means open plan wherever possible. By compartmentalising the boat as you have this is hard to achieve. Also with everything at such widely different levels, moving about may prove to be cimbersome.

Lastly there is the height - at just over 3m it may prove to be a problem for our CG.

But like I said to start with - you've certainly been thinking outside the box.

Now, I've just spent 3 lovely days away on my boat - cool at around 14C during the day and 6C at night - but calm, sunny and generally rather pleasant! Inspirational conditions of ever there were some - so here is my latest bid. An "Extended Cab" cruiser.

Starting at the front. We have a conventional v-berth, but with a short ladder to the (sunken) foredeck providing excellent access up to the bow. The ladder would fold up much like a swim ladder does to allow an infill to create a large double berth. Behind that is the head to starboard and a large set of draws and hanging locker to port. Up just one step to the galley on the port side and the helm (raised) and refrigeration / storage on the starboard side. Up another step and there is a large (convertible) dinette and a facing settee (also convertible). A flip up leaf increase dining when necessary. A huge sliding sunroof overhead and either flip up rear windows, or simple roll up 'clears' will 'bring this area outdoors'.
Over a small step (to prevent water ingress) and out to the oversized boarding platform. This takes the place of a cockpit - with the main seating a virtual outdoor lounge, this seems quite practical. There is still sufficient room to stow a small tender or for a couple of people to fish. Steps make access to the side decks simple an safe.
Ok - lets hear it - all criticisms will be taken to heart - so congratulatory messages of support only please;) :D :p

Portager

07-22-2002, 09:04 PM

Originally posted by Willallison
Well, Mike I would have to say that your 'raised pilothouse mini-express trawler' is a breath of fresh air. Something different - inspirational even!:D

Thanks. I'll take that as a compliment. :D

Alas, I still have a few darts in my box so.......
I'm concerned that at 9.75m (32ft) we may be getting a little on the large side to meet all our weight / performance guidelines. LWL for your boat looks like being about 30ft. And of course (even though you can't bring yourself to draw it!) that there will also be an outboard sticking out back (and probably a boarding platform) so the LOA will be closer to 10.5m. We could always lop 1/2 to 3/4 of a metre off the cockpit, I suppose....

My intent was to take the space for the swim platform and outboard out of the cockpit. You might be right about the weight getting a little heavy. I think the proportions might look a little better if it were a foot or two shorter.

Then there is the relationship between the living area(s) and the cockpit. Head and galley access will of course be excellent (no trapsing through the boat with wet, sandy feet to grab a drink or take a pee...), but conversation and sightlines between those in the cockpit and those sitting inside will be difficult. The trick with a small boat is to make it feel big - that means open plan wherever possible. By compartmentalising the boat as you have this is hard to achieve. Also with everything at such widely different levels, moving about may prove to be cimbersome.

This is a valid point and I think an unavoidable aspect of the design. Every design has it's advantages and disadvantages and this is a disadvantage.

Lastly there is the height - at just over 3m it may prove to be a problem for our CG.

Nothing an inboard diesel engine wouldn't fix :D O did I say that out-loud? Same comment I had on your previous design I think. Although in mine, only the pilothouse is raised and the galley and head, with their heavy contents, are very low. I think this should compensate for the height of the Pilothouse. The benefit is good 360 degree visibility and a multi-functional space i.e. pilothouse/salon. The fact that my design has evolved to look a lot like "Portager" wasn't lost on me. :D

Now, I've just spent 3 lovely days away on my boat - cool at around 14C during the day and 6C at night - but calm, sunny and generally rather pleasant! Inspirational conditions of ever there were some - so here is my latest bid. An "Extended Cab" cruiser.

Your not getting any sympathy points from the boat-less land-locked crowd. :D Although our temps were 26C highs and 20C lows, but I did yard work. I have accumulated a collection of darts, mostly extracted from my backside, and I dying to use some of them.

I like your "Extended Cab" cruiser much better than its predecessor, although it is a little too "Clorox bottle" for my taste.

I like the ladder access to the fore deck. I was/am trying to incorporate one into my arrangement, but it has to be taller. The angled hatch may be hard to seal. Could you make the seal surface flat? The head looks a little, um, little! What is the headroom in the head? Would I have to sit down to pee? If a head doesn't have standing head room, is it still a head?

I like the hardtop/sun roof. It makes the boat lockable and I like the looks better than a soft-top. You might have removable panels that get left on the trailer to secure the aft end.

It is nice to combine the helm galley and salon into a large open space, but... I find that underway, people seam to gravitate to the helm. I don't know if it is to distract the pilot or to see where you they are going or both. The Admirable likes to sit across from the me facing forward when it is just the two of us. Also, I don't like people swing pots of hot liquids too close to me when I piloting (we chartered a boat like that once). I guess what I am saying is, for the way I operate my boat, I like my arrangement better. I'm sure you feel the same about yours. In the absence of user inputs we tend to substitute our own desires.

It appears that the longitudinal CG will be about at the helm/galley location. Do you have sufficient space for the fuel tanks under the sole? It looks like there is lots of volume under the salon and cockpit but mass placement requirements may not allow you to use some of it.

The cockpit seams a little too small. I was trying to allow space for fishing and for two divers to gear up. I think my cockpit is larger than necessary, but yours seams a little too small to me.

I like the built-in stairs leading to the side decks. Have you thought about handholds yet?

Cheers;
Mike Schooley

Portager

07-23-2002, 12:52 AM

OK, here is my O-1 rev 7 with an outboard motor.

I added a swim step or boarding platform. I didn't want to shorten the LWL so I kept length and added the platform above.

I embedded the outboard into the stern to keep the classic look.

Cheers;
Mike Schooley

Portager

07-23-2002, 01:03 AM

I know we voted on outboards, but it occurred to me that it would be quite easy to accommodate an inboard engine into the "'raised pilothouse mini-express trawler" so I had to see what it would look like.

The red striped boxes are fuel tanks. Shifting fuel between the forward tanks and the aft tank should provide adequate trim control as fuel is consumed. The blue tanks are water tanks.

The yellow blob is the Steyr diesel engine scaled to the scale of O1.

An with the outboard version, there are transom doors in the stern. There would be a rubber flap at the bottom that will allow the cockpit to self drain, but oppose waves that hit the stern from flowing in unimpeded.

Cheers;
Mike Schooley

Portager

07-23-2002, 01:06 AM

As long as I drew an outboard I figured I might as well do a stern drive version.

I shifted the stern drive as far aft as I could to retain as much space in the cockpit as possible.

Cheers;
Mike Schooley

8knots

07-23-2002, 01:33 AM

I have no darts to cast. only a few observations. I really have no right to post on this project, but I hope you all do not mind. I think she needs a little more beam up foreward She seems a little needle-like. I think at speed she will be a wet ride. This is a multifaceted + the added flair will create added interior space in the foreward cabin and reserve boyancy in a following swell. If you get cought in some ugly stuff! Back to the foreward cabin. I noticed the cabin sole is very close to the keel and ribs. Dont forget your structural elements. I have fought with this for years I have crammed everything down in the hull so far to keep good stability that I left no room for fuel, grey, black watertanks, batteries and so on! Let alone the very structure that will hold her together. I hope these observations are taken in the right context. Happy noodling! I like the profile and the Volvo DP Outdrive. 8Kts:)

Portager

07-23-2002, 01:52 AM

Thanks for the comments and compliment. I think they are right on track. Constructive criticism is always welcome. Compliments are even better. :D

Cheers;
Mike Schooley

Willallison

07-23-2002, 03:33 AM

Welcome back 8knots - far from being unqualified to speak on the subject we welcome your input - in fact we could do with a bit more....the more the merrier as they say.

In fact, how about a couple more of those lovely "1 hour sketches" of yours......

Willallison

07-23-2002, 04:09 AM

:( Sorry to hear about your butt, Mike. I feel somewhat guilty that most of those little bruises were caused by darts with my signature on them....:p

I like the ladder access to the fore deck. I was/am trying to incorporate one into my arrangement, but it has to be taller. The angled hatch may be hard to seal. Could you make the seal surface flat? The head looks a little, um, little! What is the headroom in the head? Would I have to sit down to pee? If a head doesn't have standing head room, is it still a head?

I've achieved relatively easy foredeck access in 3 ways. 1st the freeboard up fron isn't as high as yours and the front cabin top is raised. 2nd I have included a forward 'cockpit' which also makes for a more secure foredeck (drains o/board). 3rd there is a step up before you get to the ladder. This means that access to the hatch is easier and would also allow you to poke your head out before venturing on deck. Sealing the fron hatch shouldn't be too much of a problem - some decent lips and a couple of clips to dog it down against rubber seals should do the trick.
Headroom in the head is about 1.7m - not exactly palatial I agree - hopefully I can squeeze a little more in when I (if) I do some more accurate drawings. And no - if it were any less, I think I'd refer to it as the 'shoulder'!:D

The Admirable likes to sit across from the me facing forward when it is just the two of us. Also, I don't like people swing pots of hot liquids too close to me when I piloting (we chartered a boat like that once).

At 1m wide my helm should accomodate two - though if my (now 20 weeks pregnant) wife gets any bigger, I may have to revise that!;)
With a cruise speed in the mid-twenties I don't envisage doing much cooking on the run, so I don't think having the galley helm-side would pose much of a problem.

It appears that the longitudinal CG will be about at the helm/galley location. Do you have sufficient space for the fuel tanks under the sole? It looks like there is lots of volume under the salon and cockpit but mass placement requirements may not allow you to use some of it.

I would expect the CG to fall somewhere near the aft end of the galley. At the centreline, there is about 0.5m under the galley sole and 0.75m under the lounge sole. Should be more than enough room for all the tanks (approx 1.5 cubic m under the galley alone). With O-1 meant to be a relative lightweight, placement of added weight will be an issue regardless of design. There is indeed a huge amount of space available for storage under both cockpit and lounge areas. There is also plenty throughout the rest of the boat - under lounges, the v-berth, helm chest of draws etc. It will always come down to the owner to ensure that it is placed sensibly.

The cockpit seams a little too small. I was trying to allow space for fishing and for two divers to gear up. I think my cockpit is larger than necessary, but yours seams a little too small to me.

The cockpit is a little on the small side. But for most people I thought that the extra accomodation would be a higher priority and you can only squeeze so much into 30ft. Actually, there is about 1.25m in front of the outboard, so whilst it might be a little tight putting on the scuba gear, it should still be possible and with storage under the cockpit sole, there is plenty of room to store the gear when it's wet without taking it inside. The length from the aft of the boarding platforms to the forward end of the cockpit is 1.75m
From my rough measurements your cockpit is about 2m long (2.6m including the platforms which are more 'external' than mine) and you have 1.4m in front of the outboard well, so whilst it is larger, there isn't that much difference between the two.

So far, between just the two of us we have shown at least 4 completely different variations on the same general theme. All have their pro's and con's - perhaps on a single hull, we could offer a couple of different arrangementts......

Portager

07-23-2002, 10:14 AM

Originally posted by Willallison
Sealing the fron hatch shouldn't be too much of a problem - some decent lips and a couple of clips to dog it down against rubber seals should do the trick.

Don't under estimate the difficulty of sealing an angled surface. It has proven to be a complex task over the years, but for some reason we keep designing them into out designs and then crushing them after we are committed. Just a thought.

Headroom in the head is about 1.7m - not exactly palatial I agree - hopefully I can squeeze a little more in when I (if) I do some more accurate drawings. And no - if it were any less, I think I'd refer to it as the 'shoulder'!:D

I was think if it wasn't ahead it must be behind. :) Sorry, I'm a sucker for bad puns. The problem with the head forward is everything tends to stair steps up from there. If you raise the roof on the head it raises everything from there aft. If you move the head aft you have visibility and/or cockpit isolation problems. It seams to me that it all revolves around the head. I think I remember someone telling me that once, but it didn't register.

At 1m wide my helm should accommodate two - though if my (now 20 weeks pregnant) wife gets any bigger, I may have to revise that!;)

LOL. My gorgeous bride has at least 20 years and 2 kids on yours and we don't fit in a 1 meter seat either.

The cockpit is a little on the small side. But for most people I thought that the extra accommodation would be a higher priority and you can only squeeze so much into 30ft.

True.

From my rough measurements your cockpit is about 2m long (2.6m including the platforms which are more 'external' than mine) and you have 1.4m in front of the outboard well, so whilst it is larger, there isn't that much difference between the two.

Also true and I'm at 32'. My cockpit internal dimensions are 6.75' X 6' without the motor incursion. My cockpit shrunk after I wrote my previous post. Must have gotten wet.

So far, between just the two of us we have shown at least 4 completely different variations on the same general theme. All have their pro's and con's - perhaps on a single hull, we could offer a couple of different arrangementts......

True, although my first arrangement didn't have room for fuel and the second was UGLY! I think we are really left with a midget head (shoulder) forward or the head aft. I think it would be is possible to do multiple arrangements on the same hull, but every time we decide not to decide we compound our work load. Maybe eventually we could go back and do a variation if there is enough interest (internally and externally), but I think we need to focus on a primary design.

By the way, I like your hull form and I was hoping to use it for my arrangement, if it goes forward. :)

Cheers;
Mike Schooley

tom28571

07-23-2002, 04:11 PM

Mike,

I had a suspicion from the first that you would try to sneak a diesel in under that pilothouse. If that is not your reason, why did you make the pilothouse so high? Excellent visibility can be had with a much lower profile and I'd personally need a really good reason to put up with the up and down of the fore/aft passage.

Speaking of visibility and heads, having the head directly behind the helm has minimal effect on steering visibility and avoids the problem choices being discussed. Having the head aft on the opposite side of the helm does have greater effect on helm visibility since the pilot can't stick his head out of the port side to look aft.

As mentioned by 8 knots, drawing the interior without reference to the hull shape and structure will surely lead to some problems fitting things in later on.

I am still concerned about hulls that are very fine forward and very full aft in following waves. Been there, experienced that , don't like it much.

And speaking of fine bows, by the way Will, the Wally boat got some mention in the latest Professional Boatbuilder that came today.

Portager

07-23-2002, 05:21 PM

I wish I could take credit for making the pilothouse that high so that I could put the engine under the pilothouse. In reality, I did the UGLY version first and I needed the height to high to see over the head. When I moved the Pilothouse forward I decided to keep the height the same for visibility aft. You are correct, I could lower the Pilothouse a foot or so but then you couldn't see behind as well. At about 1.5' you would start running out of room for fuel and/or having to shift it some of it forward, which would cause CG problems.

As 8knots pointed out, I probably didn't make the pilothouse quite high enough to accommodate the diesel under the sole. I think I need another 6 to 8 inches to make it work. The other problem is the engine is a little too far forward so it is going to tend to be nose heavy. OTOH the outboard will be stern heavy, as would the stern drive.

As far as I am concerned the O-1 baseline is still outboard powered. I did the inboard and stern drive versions for my own edification and I welcome comments on them. If anybody objects to me posting them, then I'll delete them.

Cheers;
Mike Schooley

Willallison

07-23-2002, 06:48 PM

I did the inboard and stern drive versions for my own edification and I welcome comments on them. If anybody objects to me posting them, then I'll delete them.

No objection on my part - indeed I admire your tenacity!:D
Of course, with the sterndrive you lose 1/2 your cockpit and with the inboard you've screwed up your weight distribution and no longer have room for any fuel - but then I've been trying to tell you that for ages! He, He, He.....

Tom,
Speaking of visibility and heads, having the head directly behind the helm has minimal effect on steering visibility and avoids the problem choices being discussed. Having the head aft on the opposite side of the helm does have greater effect on helm visibility since the pilot can't stick his head out of the port side to look aft.

True, if the head is aft (without a raised pilothouse) then the best place for it is probably directly behind the helm. But you still can't compare the visibility with that achieved if it is up fwd. It isn't only for berthing etc that being able to see aft is important - being able to keep an eye on people (and particularly children) in the cockpit whilst underway is an often overlooked safety issue.
And as I was saying earlier, it also compartmentalises the spaces, making the whole boat feel smaller. Personally - provided adequate headroom can be found without excessive overall height - then I am convinced that the fwd location is best.

As mentioned by 8 knots, drawing the interior without reference to the hull shape and structure will surely lead to some problems fitting things in later on.

I am still concerned about hulls that are very fine forward and very full aft in following waves. Been there, experienced that , don't like it much.

I can't speak for Mike, but I have based all my drawings on the hullform which I have posted previously. Though with the extended cab, I have altered the bow shape a little as the completely plumb stem didn't look too flash.

Incidentally, what did you all think of that hullform? Since I posted it, I've played around with the shape a little - giving the mid-hull-side-chine-thingy (which nobody has told me what to correctly call) a little more flare. This should make the boat drier and less prone to burying the bow in a following sea.

Portager

07-23-2002, 08:22 PM

Originally posted by Willallison
Of course, with the stern drive you lose 1/2 your cockpit and with the inboard you've screwed up your weight distribution and no longer have room for any fuel - but then I've been trying to tell you that for ages! He, He, He.....
Not so fast flash! Although I am somewhat concerned with the forward CG of the inboard configuration, I am much more concerned with the aft CG of the outboard and even more concerned with that of the stern drive. It is true that the stern drive eats up a lot of space in the cockpit, but the outboard eats some too and the inboard has the best cockpit. As for fuel, I located the fuel tanks outboard of the engine so all configurations have the same fuel capacity (each tank is 60 US gallons) and water capacity (each tank is 30 US gallons). The outboard does have more storage space under the raised pilothouse though.

I think the main advantage of the outboard/stern drive configurations is the pilothouse could be lower. Tonight I'll try lowering the pilothouse on the outboard (don't think the stern drive is worth the bother) about 8" (one step) and see what that does to the looks. probably need to lower the bow too. The downside will be rear visibility and fore cabin headroom.

I can't speak for Mike, but I have based all my drawings on the hullform which I have posted previously. Though with the extended cab, I have altered the bow shape a little as the completely plumb stem didn't look too flash.

Incidentally, what did you all think of that hull form? Since I posted it, I've played around with the shape a little - giving the mid-hull-side-chine-thingy (which nobody has told me what to correctly call) a little more flare. This should make the boat drier and less prone to burying the bow in a following sea.
I was planning to use your hull form also. I like your hull form just fine, but that isn't my forte (I don't know squate about hulls:)). I was planning to use your hull form, but I need guidance.

Cheers;
Mike Schooley

Portager

07-23-2002, 11:05 PM

OK, here is the outboard version with the lower raised pilothouse. The height is now 9' overall. I had to lower the bow to make it look better. Headroom in the fwd cabin is now 4' 4". There is also a torturous jog between the pilothouse side deck and the galley/head roof.

An unrelated change is I had to narrow the head. I hadn't left enough clearance for the curvature of the hull.

Cheers;
Mike Schooley

Willallison

07-23-2002, 11:38 PM

Here's another variation on the Raised Pilothouse theme.
The main salon is of a wide-body configuration, giving excellent internal volume. However, it means you must climb a ladder from the cockpit and go over the salon to reach the foredeck. The raised helm is only a step or two up and contains nothing more than the helm and companion seats. The v-berth is in the bow, with the same foredeck ladder access as before.
The heghts need to be played with a bit - the whole thing could be a little lower - though as it is with the salon floor at chine level there is ample room for tankage beneath.
Whaddayathink?

duluthboats

07-24-2002, 01:24 AM

“what do you call that thing...the sort of chine thing 1/2 way down the hull sides”

To me it is just a chine.

“It gives the boat a more 'traditional' appearance - but I know you old guys like that!”

You shouldn’t talk about Tom that way. ;)

I won’t bore you with any excuses as to why I haven’t been helping. Let’s leave it at, “I’m busy.” I have been watching from the side lines. I must say, you two have been tearing up the field. I was leaning towards Mike’s troller. Then Will posts this layout that is perfect, for me anyway. Not much I would change. Maybe the pilot house windshield could be vertical. A few old guy things like that and I could like this one.
Gary

Willallison

07-24-2002, 01:54 AM

Couple more thoughts on the raised pilothouse front.
The first is a modification on the wide-body salon - you often see it on bigger 'trawlers'. There is a side deck running the full length of the stbd side, but only as far aft as the salon on the port side.
I've also included space on the outboard bracket for an auxhillary, which we've conveniently been omitting up till now.The 2nd is a variation on both. With the narrow (250mm) sidedecks running down both sides of the salon and wider (about 400mm) from the pilothouse fwd.
In both cases I've drawn a ladder leading to the side deck just aft of the helm - could be handy, but if not you could put a small cupboard there.
Both are also a little shorter at 9m (hull)

These are just ideas - personally I prefer my extended cab idea - too many steps etc in the raised pilothouse for me.......

Willallison

07-24-2002, 01:55 AM

“what do you call that thing...the sort of chine thing 1/2 way down the hull sides”

To me it is just a chine.

Suppose so - what's a knuckle then?

Portager

07-24-2002, 02:24 AM

Will;

I like the arrangement. I think the full width cabin is a good approach for such a small boat. Interior space is worth having to climb the ladder and go over the roof.

One thing you might try is to use just one step going into the pilothouse and then another step up to each seat. This allows through traffic to only go up and down one stair. You could also use a flip up foot rest to allow standing headroom at the helm and lower the roof, but then the aft pilothouse windows would be very small.

Here is my latest version. I added a one foot grid pattern and I incorporated a ladder into the vee berth fill. The fill is hinged at the forward end and the ladder steps are on the bottom side. The fill pivots up to the hatch where it latches in place.

With the lower pilothouse roof the are only two steps up to the pilothouse and two down to the forward cabin. There is a third step up to the seats in the pilothouse.

Cheers;
Mike Schooley

tom28571

07-24-2002, 04:37 PM

Mike, I think that your boat is becoming, how can I say this, less ugly than the original. I know that is only a backsided compliment but it is my feeling about it. I still see no need for the high pilothouse and expect it to be a problem on a long, narrow high windage hull like this. I think you fear about both visibility and outboard weight on the stern are not real problems.

Take a look at how Devlin sets up his boats. They don't suffer from poor visibility and don't have such height, even on more beamy and heavy hulls.

Another thing is that I consider my crew mate important enough to have a good forward facing seat with good visibility.

I think that there is a consistent push to steer the O1 concept toward a bigger, faster and more complicated boat than the original concept. If the current proposals are for O1, what will the more extensive concept be like and where will a simpler boat fit in.

The 120 gallons of fuel will run my boat over 1000 miles, not 300. 60 gallons of water might last me a season. Together, the tankage is over 1400 lbs!! How will the boat handle in empty versus full tank configurations?

Rant of the day.:D

Portager

07-24-2002, 05:34 PM

Originally posted by tom28571
Mike, I think that your boat is becoming, how can I say this, less ugly than the original. I know that is only a backsided compliment but it is my feeling about it. I still see no need for the high pilothouse and expect it to be a problem on a long, narrow high windage hull like this. I think you fear about both visibility and outboard weight on the stern are not real problems.

Well I am sorry you feel that way, but thanks for the feed back. If you go back to my original configuration it was very similar to the Devlin Surf Scooter and much lower and better looking. My problem was I had no place for fuel, and equipment so I had to raise something. I'll admit that I probably went overboard, but it was kind of a natural progression.:) Know that I understand your concerns, I'll try and address them.

Another thing is that I consider my crew mate important enough to have a good forward facing seat with good visibility.

So do I and I like to her to be able to sit abreast of me. That is why the port side seat slides fore and aft and the backrest reverses. With the table down and the seat slid aft all four seats in the pilothouse face forward and are at the same level as the helm. The two front seats can slide forward and by reversing the back rest and raising the tables, you have two booths with seating for four separated by an isle. With the table lowered to seat height and a cushion fill-in you have two berths. I thought this was a very functional arrangement.

I think that there is a consistent push to steer the O1 concept toward a bigger, faster and more complicated boat than the original concept. If the current proposals are for O1, what will the more extensive concept be like and where will a simpler boat fit in.

In my mind the difference between the low end and the high end is the equipment. I don't think you can reduce cost much by reducing structure on a home built boat. If labor is free then cost is a driven by material cost, so to reduce cost you need to eliminate high cost items or replace them with low cost items. In my mind; the low end gets a small engine and the high end gets a bigger engine. The low end gets an ice box instead of a refrigeration system. The low end gets a camp stove instead of a Yacht type stove/oven. I was also considering a sun shower in the cockpit or a solar water heater on the roof instead of an expensive water heater. OTOH if O1 is going to be upgradeable, you need to design it to incorporate the high end equipment that could be installed some day. It is much easier to leave something out that was designed in than to add it as an after thought.

The 120 gallons of fuel will run my boat over 1000 miles, not 300. 60 gallons of water might last me a season. Together, the tankage is over 1400 lbs!! How will the boat handle in empty versus full tank configurations?

I thought the goal was a weight of 5,000 lbs and cruise at 22 to 24 knots. For that weight, speed and range plus reserve I calculated that you would need between 100 and 120 gallons of fuel. I provided for 120 gallons forward and 60 gallons aft to allow for trim adjustment. Maybe I am being over concerned, but I haven't calculated the numbers yet. The requirement was to maintain 2 people for a week cruise. I know when I take a week off I use both weekends, so I assumed 10 days. With 2 people for 10 days I allowed 3 gallons per day per person. With showers I think this is comfortable but not extravagant. Am I wrong?

Cheers;
Mike Schooley

Willallison

07-24-2002, 06:53 PM

I think that there is a consistent push to steer the O1 concept toward a bigger, faster and more complicated boat than the original concept. If the current proposals are for O1, what will the more extensive concept be like and where will a simpler boat fit in.

You make a valid point here, Tom. The more complex the design becomes, the more difficult (and probably) more expensive it will be to build - narrowing its appeal somewhat. Further, it will add to the weight, which is going to be the enemy throughout this project. OTOH you really have to define what 'cruising for a week' is to be. People like yourself (and I say this somewhat admiringly) are prepared to do without a number of things in order to achieve a simplicity of design and to kepp weight to a minimum. Others won't leave home without every conceivable knick-knack and appliance. They are prepared to wear the cost of lugging all that stuff around.
I lie somewhere in the middle. I like to be able to shower - perhaps every 2nd day (though I'm reasonably frugal with my water use). I like to be able to light the heater, the bbq and the cooker. I like to take my dogs and my dinghy (lightweight, roll-up inflatable) etc etc. I'm still mindfull that everything I take aboard, I have to cart around and will adversely effect my economy and performance.
Some of the concepts that Mike and I have shown so far may lean a little too far to the condo end of the scale - my extended cab, for instance (still my favourite) is shown with a nice swoopy, curved cabin roof. Makes for a nice drawing, but I'd hate to try and build it out of plywood!
But it is equally important to make sure that we not restricted to a boat which by its design can only lie at the camping end of the spectrum.

I thought the goal was a weight of 5,000 lbs and cruise at 22 to 24 knots. For that weight, speed and range plus reserve I calculated that you would need between 100 and 120 gallons of fuel. I provided for 120 gallons forward and 60 gallons aft to allow for trim adjustment. Maybe I am being over concerned, but I haven't calculated the numbers yet. The requirement was to maintain 2 people for a week cruise. I know when I take a week off I use both weekends, so I assumed 10 days. With 2 people for 10 days I allowed 3 gallons per day per person. With showers I think this is comfortable but not extravagant. Am I wrong?

I've been aiming for an all-up weight of around 1800kg (4000lbs). I'm sure Tom would like us to shave a few hundred more out of it too!:D At 5000lbs I think it becomes too cumbersome as a trailer boat and (though I haven't done the numbers) I'm not sure that we'd meet our performance goal with just one motor.
If O-1 is to be at all economical, then a fuel capacity of 80 US gallons should be enough (4 nmpg) If we could achieve 5 nmpg then 60 would be enough, if you don't allow any for reserve. As for water, I reckon your pretty much on the money - with my two dogs (who consume quite a bit of water), my wife and I can last about 5 days on the 30 gallons aboard my boat.

Willallison

07-24-2002, 07:05 PM

Tom,
thinking about the weight and getting back to the bottom loading.
My hullform has a waterplane area of 9.7 sq.m
At fully loaded displacement of 1800kg, you have 185 kg per sq.m
Or at 65% of AWP, you have 285kg per sq.m
Too heavy?

tom28571

07-24-2002, 10:48 PM

Mike,

I meant no insult, just wanted to jerk things around a bit and see if I could determine where the design was headed. At this point, there is no design, there are just kind of wish sketches. I think there is a strong possibility that many of the things in this wish sketch are not compatible with a trailerable boat to go to sea in.

Many NA's would say that to go to sea, a planing hull should have a bottom loading of at least 75 lbs/sq ft loading on the planing waterplane (367kg/sq m). That makes Will's boat over 5000 lbs and Mikes about 6700 lbs, I expect. I think that is incompatible with the supposed simplicity of O1. I have trailed a 4500 lb boat and don't like to do it other than on short trips. Such required loading for operation in an offshore environment also pretty much eliminates any economy or comfort of planing ability at the lower speeds. "Liz" runs about 41 or so lbs/sq ft, so, even if we do take her into some rough water at times I know that she is not suited for the big stuff and make no long planed excursions into it.

This has been part of my argument. I just don't see an 8 ft 2 inch beam, 30/32 ft monohull that can operate at 30kts and cruise at 22-24kts in any substantial seas as being compatible with the simple goal of short week end to a week cruises with a substantial trailing distance on each end. If you want to go to the same nearby places all the time, then a larger non trailerable or merely transportable boat will do. Then the higher speed goals make more sense as you may want to extend your range more.

The smaller boat that is more easily and economically trailed greatly expands the cruising range without the complications.

We found this out when I was transferred to a city too far from our cruising keelboat on the coast to make weekend trips. We sold the keelboat and bought a 22 ft swing keel Catalina as a compromise. Turned out to be the best thing we ever did in boating. We went farther, faster and cruised areas that we could never have been able to get to in the bigger boat in limited vacation times. We did not mind the smaller size and more limited acommodatio since we were on the boat for much shorter times. Water and fuel and showers can be had at intervals.

This experience led us to buy a campervan when I retired. It has all necessary ammenities other than a shower. In it we have visited all 49 states, all but one Canadian Province and Mexico. We travel rather than set up camp as the owners of the big rigs tend to do because of the complication of setting them up. Around the campfires, our discussions are about our travels and what we have seen and experienced rather than about our camping rigs and how to fix the many things that go wrong with them. We see the same thing among our cruising boat friends, both sail and power. The bigger and more complicated the rig, the more people seem bounded by them and their problems and limitations. In our small boat we cruised the Florida Keys for five days without backtracking and then hauled our boat 700 miles back home and still had a day to rest up before going back to work, all in one week's vacation.

It isn't that I don't like air conditioning and a furnace but we can take our small boat to Georgian Bay in the summer and Florida in the winter. For nearby cruises it's easier to just pick suitable weather than to provide for all eventualities in one boat. I've traveled on boats with other peoples dogs/pets and they also tend to dictate the limits of what and where you go, so we forego them also.

Sorry to run on for so long but I think the background may make my comments more understandable. And Mike, I still think your boat is too high on a long, narrow beam hull.

Willallison

07-24-2002, 11:47 PM

At this point Tom, I think it is time I riminded you about participation rule #1:D
Participation Rule #1
"Ye shall not laugh at another's drawings until ye hath posted something superior!"

I understand your desire for simplicity and lightweight, as I've said before - so come on - it's time to put up - let's see your sketch(es).......

Disclaimer: As always, the above is put forth in a lighthearted manner, I hope you receive it as such

I agree that the heavy bottom loadings that you refer to would probably make for a more comfortable high-speed rough-water performer, but I don't think anyone is suggesting that the 22 knot (max) cruise and 28 knot max that we have set for O-1 should be achievable regardless of sea state. One of the fundamental objectives that we set ourselves was that the boat should be able to maintain planing down to about 12 knots - partly in order to allow economical speed variations to suit the conditions. (That doesn't preclude a slightly finer entry to improve rough-water performance).
That is why I've worked on a displacement of 1800kg. I believe that it will allow for a reasonable compromise between utmost simplicity (and light weight) and lard-assed complexity. If he was prepared to do without things like hot water etc, a clever builder could probably pare that back to about 1500 and install a smaller motor.

To some extent I agree with your thoughts on towing large boats - I reguarly tow our dive boat (at a combined weight of 4300kg - note kg not lbs) all over the state. And I've trailed my own 27 footer (LOA is actually 29'10") up and down the East coast of Australia. It is a more involved process than tossing a ski boat on the back, but with the right vehicle it isn't a particularly big deal. However, it requires a far greater investment in tow vehicle, trailer etc etc. Which brings me back to the 1800kg displacement I've had in mind - on trailer its combined weight would probably be around 2200kg - I think a reasonable compromise.

At this point, there is no design, there are just kind of wish sketches
By preparing preliminary sketches we aren't exactly breaking new ground - it's certainly how my Westlawn course says you should go about designing a boat.
So as I said up top - show us your ideas - and bare your ass for the darts that will surely follow!!:D :D

Portager

07-25-2002, 02:06 AM

Tom;

I'm not insulted. I understand your point and I agree with Will. If you have a big enough truck and deep enough pockets then towing a big trailerable boat is no problem, but O1 isn't for the deep pockets crowd.

In Dave Gerr's book "The Nature of Boats" on page 107 he provides a curve of comfortable heave on a graph of waterplane area versus displacement. At 2.5 tons or 5,000 lbs he shows that the waterplane area should be below 120 sq ft. This equates to 41.67 lb/sq ft. At 12.5 tons, 25,000 lbs the waterplane area should be <330 or 75 lb/sq ft.

If we use Dave Gerr's curve and Will's waterplave area of 9.7 sq m or 104 sq ft, then we should have a weight >2 tons or >4,000 lbs for comfortable heave. Treating this as the minimum or empty weight and adding 100 gallons of fuel (600 lbs) and 60 gallons of water (480 lbs) puts you at 5080 lbs. With personal equipment and gear I figure the maximum weight would be 5,500 lbs. If you used a "Fastload" aluminum trailer http://www.fastloadtrailers.com/model_sheet.htm the trailer would weigh 940 lbs. This brings the total weight with trailer to 6,500 lbs. Now I agree that this is too much to tow with an average vehicle, but it isn't too much for a large SUV or pickup.

Now to go to an empty weight lower that 4,000 lbs, I think you should reduce the waterplane area. If you go to a lighter loading then you need to flatten the bottom and then it is going to start pounding.

Cheers;
Mike Schooley

Willallison

07-25-2002, 02:52 AM

As one of the greatest all-time fence-sitters, I'm going to partially jump ship here and side with one leg on Tom's side of the fence.
It is true that if one of your objectives is to be able to maintain a given cruise speed almost regardless of the conditions, then heavier is almost always better. But heavy also comes at the cost of economy.
By running a reasonably low bottom loading and with a relatively light displacement you can vary your speed without falling into semi-displacement mode and suffering much higher fuel consumption. This boat would be very unpleasant running at 25 knots through a 3 foot slop - leaping out of the water and pounding like mad. But being able to slow down to 12, 15, 18, 20....whatever means that you can slow to the point where the boat no longer flies off the waves, but simply goes up one side and down the other.
My father often relates how the best sea boat he ever owned was an 18 foot runabout with a small cabin. It had a very shallow deadrise and was quite light - able to maintain very low planing speeds, you couldn't discern the transformation from displacement to planing.
Anyway, I digress...
As always, there is a compromise to be suffered here. At 1800kg (or thereabouts) the boat is not as light as it could be, so it won't be as economical as it ultimately could be. It won't be heavy enough to run fast in rough water. It won't allow for every conceivable option to be carried because that would make it too heavy.
But it will be easily manageable. You will be able to tow it behind a mid-size 4wd or large sedan. It will be reasonably economical. It will offer enough creature comforts for those who don't want their boating to be confused with camping. It's a compromise and I still think it's about right;)

tom28571

07-25-2002, 08:59 AM

In designing a couple of houses, I've found it much better to start with a small plan that meets minimal requirements and then adding space and features where they are most needed to satisfy desires while ballancing the added costs (all kinds of costs). Starting with the ultimate and then backing off to reality is a much more difficult process and far less satisfying since the feeling that we are continually giving up something grates a bit.

OK here is the boat that I now use. It's been on the forum since before the O1 project started. Why do I reintroduce it? Because all in all, I don't want to add very much to meet the O1 goals, at least to my satisfaction. It has all we need now and with minor modifications meets all but high speed in rough water.

http://a7.cpimg.com/image/75/66/8756597-960b-0200016B-.jpg

What to add or change?

*More power - a 90hp max I now can get 24-25mph in ripply water so 90hp will easily push it over 30.

*More tankage - My range is now 200miles and fuel load will need to be increased to about 36 gallons plus the differential for the bigger engine.

*Water tankage is now 30 gallons and I don't see the need for more.

Hull changes -

*A bit longer to support added engine and fuel load. Increase bottom thickness to 3/4 inches by laminating a layer of 1/4 ply over the formed bottom to handle added stress in rough water.

*Increase the aft deadrise a bit as the added displacement allows to, say, 12 degrees.

*Maybe look into adding a pad under the aft keel and increasing deadrise further.

*Reduce longitudinal angle of the planing chine flats if they introduce handling problems in high speed maneuvers (chine tripping).

Whether this boat will have the excellent low speed performance of "Liz", I don't know, but I have doubts.

Portager

07-25-2002, 10:28 AM

I can tell I'm going to loose this argument, but this battle has raged for decades and has been lost by better engineers than me. I'm not going to build O1 anyway, so I'll just go with the flow.

Tom;
Can you add a shower to the list of changes? I thought we had agreed on a hot shower.

I guess how you equip a boat depends on how and where you intend to use it. When I go to Mexico, once I leave San Felipe I'm not going to get a shower or potable water until I get back. The next fuel is 225 miles and the gulf doesn't get interesting for until you go 400 miles. It is worth it, the diving and fishing is spectacular. O I forgot, no air refills for 800 miles.

If I built O1, I'd get the Admirable to go with me once. They when I went boating I'd be a bachelor. This might work for a weekend now and then, but not for 5 weeks of vacation a year. I see no value in building a boat that I'll never use. I should either waste, I mean invest :) more money of none. That is why Portager is 36' long, has all the comforts of home and a SCUBA tank compressor onboard.

Cheers;
Mike Schooley

ErikG

07-25-2002, 10:47 AM

Mike, it's good and well if you can spend that much on a boat.
For O1 I believe we set a price of no more than 50K$ if you do it yourself. To me that is still quite a lot of money. Personally I'd like it to be a lot cheaper than that for homebuilt, but hey, I might not be totally realistic here....

I also think that there is a huge difference how we all use our boats.
I for one use mine in the baltic sea (swedens east-coast). We also have one of the worlds finest archipellagos here, thousands of islands. And I might not (typically) go more than say 100 NM on a cruising week, probably at lot less. Because when I go on a powerboat the goal is the largest goal. I go somewhere anchor in a beautiful bay, fish some swim some, take a long walk looking around the island e.t.c.
Just "powering" around is not my idea of cruising (in a powerboat that is). Sailing, well thats a differnt story.

Mike on the otherhand needs to go to Mexico during the cruising week. Probably 'cuse there's not to much to see on the way. So he'll need a whole lot of fuel.

We need to decide who (what kind of user) O1 is supposed to appeal to.

My own sketches will follow in a day or so

Erik

tom28571

07-25-2002, 12:44 PM

Mike,

I don't think it is possible for you to "lose" the argument since we are really just tossing ideas at each other. Naturally these ideas reflect each persons bias and preferences. If everyone agrees with me, then I don't learn anything.

Reading about your proposed cruise, I understand what you want in a boat although I did not view that as our intended scenario. I have not been in the north Baja area but in the area between Santa Rosalia and Loreto we had no problem finding drinking water in gallons and tank quantity. A lot cheaper than in the US too. Even ice was readily available. The road along northeast Baja is dirt and pretty rough so we avoided it. I hope you intend to go in the winter since summers can be brutal there. Mexican officialdom can sometimes be overbearing also. It's a beautiful cruising area though and certainly not crowded.

ErikG

07-25-2002, 07:40 PM

I haven't been that unvolved in the O1 so far, much to much sailing to take care of :). Now I've started working again, so here's my first sketch.

It's just a computer sketch nothing fancy. Interior pic speaks for itself except the helm seat, it can fold up to make space for a standing stearing position.

One could use a top like on Tom's "Liz" but that depends on what look we want O1 to have, I like Tom's distinctive "retro" styling. But I think this project should be "sellable" to normal people and not just to us, so I think a more modern styling would "sell" better.

I have included a large galley because it's nice to be able to cook properly.

I still thinks it looks way to much like a rocket! But I don't think theres to much one could do while being legally trailerable.

Aaaahhh, I can't wait 'til I hear thoose "zzzzziiiinnnggg" sounds with the occasional "Ouch - aim at the drawing will ya".

Erik

b_rodwell

07-25-2002, 08:47 PM

Could the hull form be changed slightly?

I don't have a lot of experience with motor boat hull forms. However.....

Will's shape looks fine except for building it in flat sheet construction. The horizontal flat next to the chine would add to the complexity of construction in flat sheet. This would translate to extra time, cost and probably slightly more weight. Would there be a lot lost if this flat was taken out.

One other question - are all the surfaces developable?

________________
Brian

:)

Portager

07-26-2002, 12:37 AM

OK Tom I try this one more time.

First, my purpose in mentioning the conditions in Mexico was to point out that not all people share your or my needs and requirements. Most are probable somewhere in the middle. I think the intent of O1 should be to satisfy the middle part of the bell curve of those requirements, thus satisfying the maximum number of potential users. If we design for either end of the bell curve we will satisfy a very small group. Now all that being said the real problem is finding the middle of a curve we can't see.:)

Now to address the waterplane area to displacement ratio. My understanding is that through years of experience Naval Architects have determined that people find excessive heave to be uncomfortable. Heave is defined as the rate of change, or the derivative of acceleration, or the third derivative of position, the first derivative being velocity and the second being acceleration. In boats heave is primarily in the vertical direction and worst on the fore deck. Acceleration is equal to force/mass and assuming constant mass, heave is equal to the rate of change of the pitching force. The rate of change of the pitch force is a function of the slope of the waves, the relative speed of the wave relative to the boat and the change in waterplane area versus depth. If all this is too complex, go to http://pws.prserv.net/fmyers/HCFactor.html and use the Heave/Comfort factor calculator. Put in 28' to 31' ft length and 8.2' beam and adjust height until you get a comfort factor of 64. Now ask yourself if you want a boat that is comfortable on the road or comfortable on the water.

Will;
Slowing down and going over the waves sounds good but what about when the waves are coming at you fasted than you want to go over them? Or what do you do at anchor when the local ferry hits you with a wake?

There is no substitute for mass to make a boat comfortable on the water. A light weight boat is fine for small lakes, rivers and shelter harbors and water ways, but for comfortable ocean cruising you just can't cut corners.

The best news is we have gotten some more contributors. Maybe we should argue more. :D

Cheers;
Mike Schooley

8knots

07-26-2002, 01:39 AM

Just a quick note. I plan to have the 2 hour sketch by the weekend. so get em honed. Mooooore great sketchers out there I see. Great work. Mike...do you have a job or are you retired? It would take me days to compile all the great info and stats you provide! 8Kts

8knots

07-26-2002, 01:43 AM

Hey
What construction method did you all decide on?
FRP or ALUMINUM or does it matter at this stage in the game?
:confused: 8Kts

Willallison

07-26-2002, 02:58 AM

Will's shape looks fine except for building it in flat sheet construction. The horizontal flat next to the chine would add to the complexity of construction in flat sheet. This would translate to extra time, cost and probably slightly more weight. Would there be a lot lost if this flat was taken out.

One other question - are all the surfaces developable?

Brian - all the surfaces are developable, so all can be produced from flat sheets. It's true that the chine adds a little complexity to the construction - though not really any more than any of the other sheets and yes it adds greatly to the design - stability, efficiency, spray deflection etc etc. You only have to take a look in any marine - there ain't too many planing hulls that don't incorporate chines.....

What construction method did you all decide on?

I plan to have the 2 hour sketch by the weekend. so get em honed.
We decided on flat panel construction - leaving the material up to the builder (at this stage anyway).
I spent all day sharpening my darts, so I look forward to your post.....;)

First, my purpose in mentioning the conditions in Mexico was to point out that not all people share your or my needs and requirements. Most are probable somewhere in the middle. I think the intent of O1 should be to satisfy the middle part of the bell curve of those requirements, thus satisfying the maximum number of potential users. If we design for either end of the bell curve we will satisfy a very small group. Now all that being said the real problem is finding the middle of a curve we can't see.

I think you have hit the nail on the head Mike - this is what I have been saying - and hello! - I am the middle of the bell curve!:D

Slowing down and going over the waves sounds good but what about when the waves are coming at you fasted than you want to go over them?

Leave the boat on the trailer.

Or what do you do at anchor when the local ferry hits you with a wake?

Pick a better anchorage.
There is no substitute for mass to make a boat comfortable on the water. A light weight boat is fine for small lakes, rivers and shelter harbors and water ways, but for comfortable ocean cruising you just can't cut corners.

In the end, this is true. But life - especially on boats is all about compromise. And O-1's primary design considerations included economy to build and operate and easily trailerable - not ocean crossings. With a boat like this you go where you want, when you can - not where you want, when you want.

I think we probably need to define our "one week cruise" a little more definitely. To me it means cruising mostly in 'sheltered' waters, coastal hopping and occaisional trip in exposed waters when conditions permit.

Tom,
OK here is the boat that I now use. It's been on the forum since before the O1 project started. Why do I reintroduce it? Because all in all, I don't want to add very much to meet the O1 goals, at least to my satisfaction. It has all we need now and with minor modifications meets all but high speed in rough water.

I don't actually recall a decision requiring high-speed rough water operation. My desire to increase fwd deadrise is simply to improve all round rough water performance.

None of us would argue the success of "Liz" - she has obviously met all of your design considerations, so could not be considered otherwise. And as I've stated any number of times I admire your single-minded pursuit of lightweight and simplicity. But, given that O-1 is not a design based around any one person's requirements (as Liz and Portager both are) she must satisfy the needs of a greater market. I believe that market would want a little 'more' in their boat.
I think the raised pilothouse concept goes too far, and Liz doesn't go quite far enough - the compromise (there's our favourite word again!) is to be found somewhere in the middle. (And I still think that both my original "express cruiser" and "extended cab" concepts lie in that middle ground {water?})
;)

Erik,
Welcome to the dart board!!
With a little imagination, your boat is very similar to the hard-top version of my original "express cruiser" concept. I agree that we should consider more modern styling - it's very much a matter of taste - but I don't know if you've noticed, but all these other blokes like the older tubs....;)
You might want to raise your chine up forward of about amidships. As you've drawn her, your boat would slam shockingly in rough water.

Willallison

07-26-2002, 03:07 AM

Just had a thought.
Once we've finished O-1 (in 2020:p ) perhaps we could move on to some other projects - we could stick our beaks into 'Portager' and give Mike some much needed assistance;) . Or perhaps we could work on 'Big Liz' for Tom, maybe a wooden masterpiece for Gary to carve out, or a triple engined super-peedster for Jeff (am I the only one who's noticed his obsession for all things big, fast and thirsty?!?:D :D

tom28571

07-26-2002, 08:20 AM

OK Mike,

I ran that heave calculation and found that I could make "Liz" into a nice riding boat by increasing the displacement to 7800 lbs or by reducing the waterline beam to 2 ft 4 inches. Neither is acceptable.

Having spent almost three years on a Gearing class Navy destroyer, I expect I know what the term heave means. It means leaving your stomach about 30 feet above your head and losing your dinner over the side.

I have driven "Liz" into waves coming faster than I wanted to go and can readily agree that it's tough and would take Will's advice and stay in port unless I just gotta go. A 35kt northeaster in water only 15 to 19 feet deep with the crests confused, very close together, very steepfaced and moving at over 10kts at me. Such conditions keep any sane person in any boat in port but we were trying to get back to homeport and crossed a piece of water recognized as one of the worse on the east coast that we could have waited out in a sheltered anchorage. This is pilot error not equipment or design error.

You are right about the comfort zone though, even if the formula is too simple minded to actually use without already understanding the process.

I know that my boat is not acceptable to the mass of boat buyers but, thinking back, that is exactly why it was designed and built in the first place. There are no boats like it on the market so I clearly am missing the center of the bell curve or even high up on the side of the bell. A sucessful boat dealer tells me that you can not make a boat too fast or too powerful or have too much stuff on it or make it look too spacey to appeal to the the mass buyer. Will, that IS the center of the bell curve.

Portager

07-26-2002, 04:54 PM

OK, as long as we all understand that O1 is intended to be an economical boat intended for sheltered water and/or fair seas.

Originally posted by Willallison

"O-1 is UNLIKE any other express cruiser on the market. She (Loyds may have dropped the title, but buggered if I'm going to!:D ) is a lightweight, comfortable mini-cruiser: home buildable and legally trailerable world-wide - by design, O-1 will be economical to build, own and operate."

I guess comfortable here was referring to the accommodations and not sea keeping? In my way of thinking lightweight and comfortable don't really go together.

I think we need to start defining a weight budget for O1. It is all pie in the sky until you start adding up pounds and dollars and then reality starts sinking in (O, bad wording:)).

By the way "Portager" with half full tanks rates a perfect 64 on the heave comfort calculator. That is what Portager is all about. I like to think lots of people would appreciate Portager if they could afford it. Since I can afford it why should I compromise? I was asked once what boat I would get if I won the lottery. I have given that much thought and I decided I would get Portager. It can go anywhere I want to go and portage around where I don't want to go. One more thing. I would appreciate into on Portager (although I won't loose any votes on Portager) but I hope to have many miles on her before 2020.:D

Cheers;
Mike Schooley

Willallison

07-26-2002, 09:24 PM

I know that my boat is not acceptable to the mass of boat buyers but, thinking back, that is exactly why it was designed and built in the first place. There are no boats like it on the market so I clearly am missing the center of the bell curve or even high up on the side of the bell. A sucessful boat dealer tells me that you can not make a boat too fast or too powerful or have too much stuff on it or make it look too spacey to appeal to the the mass buyer. Will, that IS the center of the bell curve.

As is so oft the case, I sadly must agree with you Tom - I say sadly because that is the centre of the bell curve. There is no doubt that we should be aiming O-1 at a niche market. You can't compete with the likes of the Brunswick corporation who build for just that buyer.
And there is definitely a niche for boats like 'Liz' - but I think there is a bigger niche for a slightly up-specced and up-sized 'Liz', which is where I think we should be aiming. By necessity, that would result in a slightly different and marginally heavier boat.

I think a target displacement is a good idea - even if it just a ball park figure to more accurately define the design.
Once more, I suggest 1800kg - 820 lbs

Portager

07-27-2002, 12:21 AM

Originally posted by Willallison
And there is definitely a niche for boats like 'Liz' - but I think there is a bigger niche for a slightly up-specced and up-sized 'Liz', which is where I think we should be aiming.

I agree, Will.

It occurred to me that the market niche for Portager is probable smaller than the market for 'Liz' or should I say 'BlueJacket'?

I think a target displacement is a good idea - even if it just a ball park figure to more accurately define the design. Once more, I suggest 1800kg - 820 lbs

I think you divided when you should have multiplied. 1800 kg should be 3960 lbs. Is this fully loaded or empty? If the fuel capacity is 80 gallons that is 480 lbs. 60 gallons of water would also be another 480 lbs. I don't know if these quantities are correct but if it adds then the fully loaded weight is ~5,000, if it subtracts the empty weight would be ~3,000. I can agree with the 4,000 lbs empty and 5,000 lbs fully loaded, but I think 4,000 lbs fully loaded and 3,000 lbs empty would be too low to meet our stated objectives.

Cheers;
Mike Schooley

Portager

07-27-2002, 01:03 AM

Erik;

I appreciate your participation. The more participants the better.

I really don't want to "zzzzziiiinnnggg" you, but I am concerned with the headroom in the shower. I thought one of our objectives was a standing headroom shower.

Originally posted by 8knots
Just a quick note. I plan to have the 2 hour sketch by the weekend. so get em honed. Mooooore great sketchers out there I see. Great work. Mike...do you have a job or are you retired? It would take me days to compile all the great info and stats you provide! 8Kts

You smooth talker, you don't need to worry about my darts. The tips are all bent from hitting my hide. Appreciate the compliment. I do have a job. I am a full time engineer. I am just very experienced at using search engines.

Originally posted by tom28571
I ran that heave calculation and found that I could make "Liz" into a nice riding boat by increasing the displacement to 7800 lbs or by reducing the waterline beam to 2 ft 4 inches. Neither is acceptable.

The 7,800 lbs sounds OK to me. If you restrict it to displacement speed it wouldn't take much power or fuel, just a lot of time. If I were retired, I'd find it acceptable.

Cheers;
Mike Schooley

duluthboats

07-27-2002, 11:31 PM

“Will's shape looks fine except for building it in flat sheet construction. The horizontal flat next to the chine would add to the complexity of construction in flat sheet. This would translate to extra time, cost and probably slightly more weight. Would there be a lot lost if this flat was taken out.”

b_rodwell

Well we all know I don’t know a thing about planning hulls but this is my take on the small horizontal flat. With out this O-1 would have trouble planning at slower speeds. It will not increase the difficulty of construction and will act as a stringer down the side, increasing the stiffness of the hull.
:eek:

Gary

8knots

07-28-2002, 01:04 AM

The two hour sketch
O.K. here we go…. This is the first attempt at 01 for me in quite a while. I will post and leave you to critique her as you all see fit. I must admit I have not done any real math or numbers games on her YET! I am waiting for the reaction of you all before wasting any time on that sort of fun.
PARTICULARS are as follows
LOA 33’5”
LWL 29’3”
BEAM 8’2” (really needs to be about 10’3” or so)
DRAFT 1’6” (drive up)
DISP ???????? we will wait and see I haven’t even done the body plan yet!

NOTES:
I have read a few articles on OB’s and I feel this boat would meet the speed requirements with a Yamaha 225hp some numbers that I have run across state 8.1GPH @3500RPM
And 24.9 @WOT @ 5500RPM Seems to be plenty of power and at about $15.000.00 within the budget of 01 Of course there is room for a twin of said engine. If at a later date or her owner has deep pockets!
I will need to revise the fore-ward cabin arrangement I can see that there is not the width required for the berth as drawn in relation to the sweep of the chine at the stem.

Portager

07-28-2002, 01:20 AM

OK, here is my next submission for the dart board. I went back to my original concept and raised the floor of the cabin to accommodate fuel and water storage balanced around the longitudinal CG.

I shortened the length to 31' because most trailers have a break point at 31'. I looked at reducing the length further, but according to Dave Gerr's book, "The Nature of Boats" O1 is better off with a higher length to beam ratio. Dave shows that the higher length/beam will allow it to go faster with a given power level and the longer length will provide better sea keeping.

The helm seat has a drop bottom to allow the pilot to either sit or stand. The forward seat of the booth on the port side slides fore and aft and the backrest reverses to allow the passenger to face forward or aft.

There is a ten inch wide side deck on the starboard side. On the port side the head extends to the full beam to maximize head room. A large galley is provided aft of the helm.

There is a wet locker at the front of the cockpit on the port side and a propane locker on the starboard side. This locker accommodates a Worthington 6 lb propane tank that is 6" in diameter and 22" long http://www.worthingtoncylinders.com/aluminum.html .

The outboard well is laid out to scale to accommodate a large outboard and an auxiliary. The main engine is on centerline and the auxiliary is on the port side leaving room on the starboard side for a transom gate and a small boarding platform. The forward end of the outboard well is closed off and a removable cover over the engines minimizes noise in the cockpit and cabin.

Cheers;
Mike Schooley

8knots

07-28-2002, 02:57 AM

Hey there Mike I like her. I like what you did to the bow in plan view. I to read a lot of Gerr as a matter of fact Just this morning while drawing the 2 hour My wife while playing catch with our 3 year old Irish Setter managed to knock over my cup of coffee on my copy of “The nature of boats” I was studying the Sea brights and I have always been into the idea of building the “H.M.POPE IIII” As you know I am a slow boat guy like yourself but There IS something to tooling around with 1600hp under the floor!!!!!! Maybe after a few decades of overtime I could afford the fuel bill. But I will say if a guy were to have a pair of these up here he would own the 6-pack charter business. 8Kts

Portager

07-28-2002, 01:04 PM

Originally posted by 8knots
Hey there Mike I like her. I like what you did to the bow in plan view.

Thanks, I am sure someone will complain about the windage of the high bow, but I like the high freeboard. It looks like it could plow through some rough water if you needed to.

I to read a lot of Gerr as a matter of fact Just this morning while drawing the 2 hour My wife while playing catch with our 3 year old Irish Setter managed to knock over my cup of coffee on my copy of “The nature of boats” I was studying the Sea brights and I have always been into the idea of building the “H.M.POPE IIII” As you know I am a slow boat guy like yourself but There IS something to tooling around with 1600hp under the floor!!!!!! Maybe after a few decades of overtime I could afford the fuel bill. But I will say if a guy were to have a pair of these up here he would own the 6-pack charter business. 8Kts

Your right about the 6-pack charter business. One H.M.Pope III would change that world overnight. Imagine a 42'9" (13m) sports fisher capable of cruising at 30 to 45 knots. I'd like to do a patrol boat version of H.M. Pope III and change the drives to surface drives. H.M. Pope weight 19,500 versus our Phantom Boat at 18,000. HP is the same but the Phantom is 40' long without the swim step and has a 12' beam. Even though Phantom has surface drives and H.M. Pope III has inboards (much less efficient at 35 to 40 knots) Phantom can only do 45 knots max versus H.M. Pope III's 55 knots. The reason is the L/B ratio of Phantom is 3.3 compared to H.M. Pope III's 4.2. H.M. Pope III power efficiency is 0.21 lbs/HP/knot and Phantoms is 0.25. The higher L/B of H.M. Pope is more than making up for the propulsion efficiency advantage of the surface drives on Phantom. Now how fast would H.M. Pope be with surface drives? I think 60 to 70 knots is possible.

For my high speed short range cruiser, I'd go with "Needle Senior". LOA 55', DWL 49' 4", beam 8', displacement 9,000 lbs. It will cruise at 35 knots on 300 HP and with her 55' length it would slice through chop much better than a shorter boats. I'd change the open cockpit to an enclosed Pilothouse :) and change the jet drive to a surface drive. With an 8' beam Needle Senior would meet the trailerable width requirement but would exceed the allowable length in most states. I'd design a gooseneck trailer and extend the bow up over the neck to minimize the trailer length.

Cheers;
Mike Schooley

8knots

07-28-2002, 05:06 PM

Why get rid of the jets? A small loss in speed will be paid for with intact fish and loss of tackle in those surface drives! My opinion (admittedly inexperienced) Is that surface drives have no place on a family or commercial charter boat. There is just too much potential hazard there. Granted, a reasonable skipper would have no problem with safety.
Anyway that is just my opinion. I have somewhere the lines for a patrol boat built for the Cuban coast guard 60’LOA or so built in ply and covered with FRP seems to me she was speedy with modest power. I will dig her up just for fun. 8Kts

8knots

07-28-2002, 05:08 PM

Sorry I will post those pics over in the gallery (http://www.boatdesign.net/gallery/showphoto.php?photo=164) so as not to clutter this thread. 8Kts

Portager

07-28-2002, 06:35 PM

I went back and reviewed my propulsion efficiency graphs. It turns out that Jets are generally considered to be more efficient than surface drives until 40 to 45 mph. Therefore, for Needle Senior, which cruises at 35 knots, your right, it would be better to stay with the water jet.

I have a hard time seeing myself fishing off Needle Senior. The last 8' is all engine room with a flush deck.

The boat that my employer owns and most of the boats I work on have surface drives. They all have swim platforms extending aft of the props. This makes for a large swim platform, but effectively eliminated the risk of injury and fish/tackle damage.

Cheers;
Mike Schooley

Willallison

07-28-2002, 08:16 PM

Well, with the weekend came the opportunity for me to sharpen up a few more darts - and now two more targets!:D

8knots -

The spilt galley is an interesting idea - though it seems terribly short on bench space. You could maybe have the backrest of the helm seat fold down to create additional bench.....

With so much rake to the stem and because the double berth requires a fair amount of width at the fwd end, you have been forced to have a fairly large anchor locker - a more vertical bow would assist to a certain extent. It also results in making the head look too small.

I don't know how carefully you've drawn your underwater shape, but as you currently have it, the deadrise increases towards the transom - not a happy state of affairs.

The cabin roof over the helm / galley area is too short - people going fwd to the front cabin, or aft to the salon will bump their heads

Other than that it is an interesting twist on the raised pilothouse concept.

Mike -

Hiding the outboards is probably a good way to go if you're after a more traditional appearence and should result in a substantial reduction in noise levels. It'd also make a nice spot to sit. Your cockpit though, is now shortened to 5 1/2 ft, which is only marginally more than my 'extended cab' - not necessarily too small, but worth hurling a dart in your butt's general direction nonetheless:p

The galley is huge, but the dinette, I think, is too small. The boat would sleep 3, but only seat 2. For O-1 to be successful, I think we must incorporate plenty of 'lounging' space - how many 31ft boats do you see where only 2 people can sit down (excluding helm)?

I don't have too much problem with your high bow - it would create headroom up fwd. Though it might adversely effect vision from the helm and would make the fordeck ladder from the v-berth a long, steep climb.

As far as the weight goes you're right - I goofed on the calculation. I was thinking 1800kg at half load - so around 2000kg fully loaded, 1600kg light.

Willallison

07-29-2002, 06:45 PM

Thank heavens we are hurling darts at one another & not the boats - they'd be so full of holes none of them would float......:p

This is my "if you can't beat 'em" concept. It runs with the 'head up' layout favoured by Tom and Mike. I'm still not convinced that this is the best approach, given the compromises that must be made to sightlines and the feeling of openness, but anyway....

I've extended the cabin roof forward to the point that it will provide full headroom to the head of the berths, which are open to the salon, increasing the feeling of space. A three-sectioned windscreen will allow for the centre section to swing up, creating access to the bow similar to that in my previous proposals. There is storage / hanging lockers aft of each berth. A double helm to stbd, the backrest flips fwd to create additional seating at the dinette which is just aft of it. Opposite is a lounge and a section of this creates further dining space with a leaf on the dining table. The head is aft with the galley opposite. A large cockpit and what we call a 1/2 pod for the outboards (part of the outboard well intrudes into the cockpit but most is 'stuck out the back') and a boarding platform with transom gate. There is a seat running down the port side of the cockpit, creating extra storage and easier side deck access.

You guys must surely have blunted your dart tips by now - pretty soon they'll just start bouncing off - give it your best shot...:D

Portager

07-29-2002, 11:39 PM

Will;

I hate to say this but I think our designs are converging. Other than cosmetic differences, our designs are not that far apart.

Maybe I'm overly paranoid, but I don't like having windows too far forward. I get concerned about green water coming over the bow.

I'm not too fond of seats facing inboard. When the going gets rough its a full time job just holding on and I get a stiff neck trying to look forward all the time.

Here is my latest revision. I shortened the galley and added a bench on the starboard side behind the helm. By sliding the helm forward and reversing the backrest you get a second booth and a forth berth.

I have extended the deckhouse on the port side and widened the port side booth. There is a side deck on the starboard side, so why do I really need one on the port side?

Cheers;
Mike Schooley

Willallison

07-30-2002, 12:08 AM

Hah! Step ahead of you there Mike - knew you old fella's would prefer something a bit more traditional......

The sheerline needs a bit of work - too straight and needs to sweep up to the bow more....

The short foredeck could be a bit of a problem - in the first one it is about 1.75m to the base of the screen (in the trad one it is 2m). Your boat has 2.75m. but in order to get headroom and foredeck access it was necessary. It could probably come back another 0.25 or so without too much problem.

As far as the ideas converging - don't get your hopes up just yet - I still think the head should be up forward where it doesn't interfere with the sightlines....:p

One quick thought on the curved nature of your bow shape - don't know how that would go from a developability point of view.... It would either be very blunt, or need to incorporate considerable flair, which would be difficult to build with flat panels...

Portager

07-30-2002, 12:56 AM

Will;

Who you calling old! Just because I like retro style boats doesn't make me old. I used to like sleek looking go fast boats too, but then I grew up.:D

I understand the headroom aspect of moving the windshield forward. It is a cleaver idea, but ...

You can have the head forward if you like. The raised pilothouse works good for that, but you will need more beam to keep the smooth side down.

I don't have much experience with developable surfaces, so I'll take your word for it. Although it seams a little counter intuitive.

Cheers;
Mike Schooley

Willallison

07-30-2002, 01:10 AM

LOL:D Sorry couldn't help myself - I find that the darts fly truer if they are attached to a personal insult or two!!:D

Portager

07-30-2002, 05:04 PM

I think we should try and list the things that we agree on for example length, maximum height, head room, stand up shower?, seats and bunks, ... Maybe we can start to converge a little faster that way.

Cheers;
Mike Schooley

Willallison

07-30-2002, 09:55 PM

Sounds reasonable - though I suspect it might be easier to list those things on which we all differ, so we can come to a compromise position on them. Looking down the following list (of things that I consider important) you'll see the we (at least Mike and I) would agree on most of them - and most of the sketches we've put forward satisfy most of the points - there's way more than a dozen ways to skin a cat......

However, for what its worth here's my list - from bow to stern:

Anchor
Bowsprit
provision for winch
safe foredeck access

Cabin
2 x permanent berths, storage under
sufficient storage for clothes etc for 1 week
standing headroom @ head of berth (1.75m min)

Head
Fulle enclosed separate head with basin, wc and shower
standing headroom (1.75m min)

Galley
sink, 2-burner cooktop, fridge (freezer?)
plenty of storage
reasonable amount of bench space
easy access to both dining table and cockpit

Helm
Sitting and standing positions (stand up with head out roof?)
Min 2 people facing fwd (double helm seat preferable)
Good sightlines to all areas of boat a priority

Main Salon
Full standing headroom (1.9m min)
Comfortable dining / lounge area for 4 minimum
able to see out whilst seated

Cockpit
Sufficient rope / fender storage
easy side-deck and boarding platform access
large enough tha 2 crew can fish etc
seating of some sort - even if just on wide cap-rail

Others
wet locker for oilskins etc
provision for tender storageprovision for auxhillary o/b
ability to place fuel / water etc in best place for CG / CB

I'm sure there's more - but it's a start....

Willallison

07-30-2002, 09:57 PM

...and just to add a little more confusion, here's yet another dart target - a trawler style O-1

Portager

07-31-2002, 01:41 AM

Originally posted by Willallison
However, for what its worth here's my list - from bow to stern:

Head
Fully enclosed separate head with basin, wc and shower
standing headroom (1.75m min)

I think that should be >=1.85m (6')

Galley
sink, 2-burner cooktop, fridge (freezer?)[/B]

You can make an effective freezer by putting salt on ice and putting it in an insulated compartment. It is best to put it in a sealed conductive container so salt water doesn't spill. If you decide you don't need a freezer, then you have two ice boxes.

Helm
Sitting and standing positions (stand up with head out roof?)

Head out roof is OK if it is my option. I want to be able to stand up without having the stick my head out.
Enclosed - weather tight
Good ventilation
Room for mounting instruments (GPS, compass, UHF/VHF radio, optional radar?)

Anchor
Self draining anchor locker
Anchor chain wash (raw or fresh water?)

Sea keeping
Capable of making short open water passages in good weather and able to survive unexpected changes in conditions.

Helm
Enclosed - weather tight
Good ventilation
Room for mounting instruments (GPS, compass, UHF/VHF radio, optional radar?)

Cabin
Energy efficient lighting
Location for small stereo/TV/VCR (I gotta watch the Lakers!)
Heater

Cockpit
Self draining
Raw water wash down
Fresh water shower

Equipment
Vented battery bank
AGM batteries (spill proof, high charge acceptance)
AC battery charger (to recharge off shore power)
Fresh water tank
DC water pump
Pressure accumulator
Water heater

Cheers;
Mike Schooley

Willallison

07-31-2002, 02:31 AM

quote:
--------------------------------------------------------------------------------
Originally posted by Willallison
However, for what its worth here's my list - from bow to stern:

Head
Fully enclosed separate head with basin, wc and shower
standing headroom (1.75m min)
--------------------------------------------------------------------------------

I think that should be >=1.85m (6')

6' would be nice - I'd be prepared to cop a little less if necessary - I'm exactly 1.75m tall and I can only just stand in the head of my Searay. It works fine (though it's rather short on elbow room...)

Head out roof is OK if it is my option. I want to be able to stand up without having the stick my head out
Guess it depends on whether you have a step up to the helm or not. Without it you could stand at the helm, with it you could stick your head out (of course if we went for a soft-top this wouldn't be an issue)

AGM batteries (spill proof, high charge acceptance)
AC battery charger (to recharge off shore power)

I think items like these should be regarded as optional add-ons - some will install them, some won't.

Portager

07-31-2002, 10:15 AM

Originally posted by Willallison
6' would be nice - I'd be prepared to cop a little less if necessary - I'm exactly 1.75m tall and I can only just stand in the head of my Searay. It works fine (though it's rather short on elbow room...)

How about we set 1.75 m as the minimum with a goal of 1.85 m?

Guess it depends on whether you have a step up to the helm or not. Without it you could stand at the helm, with it you could stick your head out (of course if we went for a soft-top this wouldn't be an issue)

I was thinking a hinged platform could allow you to stand head out or in. It also might be a foot rest while sitting.

I think items like these should be regarded as optional add-ons - some will install them, some won't.

I agree on the type of batteries, but I batteries are a necessity and the design should plan for their location and proper venting. Its a safety thing. As for the battery charger and shore power cable. I think it should be allowed for in the wiring plan. By the way where should the breaker panel be located? I'd like to be able to reach it from the helm.

How about we start on the things we might not agree on?

I think the length should be 31'. I'd like to make the length to beam higher to improve efficiency. I select 31' because to go to 32' would require a step up in trailer size with minimal value.

I think electrical power should be DC. If you need AC, like for a microwave, then use an inverter. If the builder decides he wants a generator, they could use a small DC generator. Balmar sells a 1.2 Kw DC gasoline generator for $1,995 http://www.balmar.net/PDF/BC00002.pdf 60 lbs, height 14", width 15", length 18".

Cheers;
Mike Schooley

Willallison

07-31-2002, 07:03 PM

was thinking a hinged platform could allow you to stand head out or in. It also might be a foot rest while sitting.

Excellent idea.
By the way where should the breaker panel be located? I'd like to be able to reach it from the helm.

I think that's probably a little further down the design track, but anywhere within a step or two of the helm would be best.

think the length should be 31'. I'd like to make the length to beam higher to improve efficiency. I select 31' because to go to 32' would require a step up in trailer size with minimal value.

I suspect Tom might have a thing or two to say about winding up this big - I'd like to restrict the length to the the minimum required to comfortably fit everything in. But taking a look at the various proposals put forward so far, they are all approaching that sort of length.....certainly we shouldn't go any bigger

Polarity

08-01-2002, 07:29 AM

I was all ready to join the fray with and catch a few of those darts when I had a rather terminal hard disk crash. - Ironicaly whilst burning a back up disk image onto CD!

So alas I am back to square-one of option-1. :mad:

Will be a few days !

Cheers

Paul

Willallison

08-01-2002, 06:53 PM

Our sympathies lie with you Paul......it will give us more time to sharpen the darts!:D

I think the biggest decision we have to make at this point is whether we should go for a head-up, head-down and forward, or raised pilothouse configuration. Pretty much everything else will be based around that.......

Portager

08-02-2002, 09:43 AM

Originally posted by Willallison
Our sympathies lie with you Paul......it will give us more time to sharpen the darts!:D

If I sharpen anymore I'll have nothing but nubs. They'll be like those child safe darts with Velcro for tips. What would be the fun in that? :D

I think the biggest decision we have to make at this point is whether we should go for a head-up, head-down and forward, or raised pilothouse configuration. Pretty much everything else will be based around that.......

I think your right. If the head is forward of the helm, then it has to be down and if we stick to the standing height requirement then you need a raised pilothouse or some king of raised helm. If the head is aft of the helm, then I think it is just a question of how far aft.

I think the raised pilothouse comes down to a stability question. Can you do that in a 8'2" beam? We can guess and speculate or we can do a lot of calculations. What is out stability criteria? How stable is stable enough?

Cheers;
Mike Schooley