Black locust - for a cold molded hull?

[santone]

We'll be building a 13'6 " Woodpussy and need to get the total weight of the boat up to 430 lbs. to make it class legal. We plan to use 2 layers of 1/8" cedar or mohogany veneer with carbon fiber cloth in between the layers and fiberglass cloth on the exterior. Since CEDAR OR MOHOGANY will yield a hull that substantially lighter than the 430 lbs. required in the class spec's we need to substitute or add heavier materials to bridge the gap without adding too much to the expense. Will black locust give us the additional weight we need and is it as builder friendly as the other two alternatives?

[JimConlin]

I can't imagine why you'd use carbon in a boat where lightness is decidedly NOT the problem. It's costly.
I won't comment on the materials mentioned 'cause I don't know the boat's construction.
With that kind of a weight target i'd be looking for ways to lower the CG. A solid lead keelson?

[santone]

The carbon fiber cloth is to make the hull "stiff". We plan to build with two layers of veneer instead of three, which is typical of construction of these smaller boats. This will simplify the construction process. We'll check with the USWPCA to see if we can use lead to add weight.

[JimConlin]

I was joking about the lead.

[Bruce Hooke]

The most desirable place to add weight is low down in the center so if the class rules allow you to get to the specified weight I would certainly go with added ballast rather than added hull weight.

[windfall]

Locust is decidely not a good choice for cold molding. It takes epoxy only moderstey well, becomes brittle in thin planks, and is virtually unavailable in long clear material of any volume.
Build the hull the way you want to, and then ballast her to acceptable wieght.
430lbs for a 13'6" boat is remarkably high....

[Wiley Baggins]

You may want to check the class rules carefully. Some rules do not allow the additional ballasting to be placed advantageously.

[Aramas]

Putting carbon fibre between the planks will have very little effect on strength or stiffness, since it is close to the centre of the material where it is subject to neither compression nor tension as the panel is loaded. The further away from the centre it is, the more efficient the laminate is in stiffness and strength - hence the high stiffness and strength to weight ratio of foam sandwich construction.

The most obvious constuction method for your situation is cedar strip - glassed inside and out, with extra layers of glass below the waterline to bring it up to weight.

[Ross M]

What Aramas said...

[santone]

The home/building plan is dead due to Woodpussy class members' concerns about possible obsolescence of existing boats. Builders are interested in providing new boats; one proposes to build a strip-planked hull with glass cloth on the exterior. A fiberglass builder is awaiting the results of an inspection of an old set of Woodpussy molds. At a session on 2/26 we'll explore these avenues. For information about the Woodpussy, visit the class website at www.uswpca.org (http://www.uswpca.org) & view some photos on my sailing site at http://24.47.49.176:8000/sailingworld/
Regards, Tony

[NormMessinger]

What Ross said!! smile.gif

[Dale R. Hamilton]

Santone- Epoxy and chopped strand mat are heavy- and add thickness and stiffness to the hull. Suggest you just build up your bottom with epoxy and CSM until you get the desired weight

[ssor]

You might consider using locust for the walk boards. It would put them at the low point of the boat and the thickness could be adjusted to adjust trim and overall weight

[Dave Fleming]

The Wood Pussy, a Phil Rhodes design of the late 1940's early 1950's was originally built in wood.
Oak ribs with Northern Pine or White Cedar planking.

I learned to sail in WP's in the 1950's on Shelter Island Sound,LI, NY,. At that time there were a number of them used by at least two summer camps.
Camp St. Regis and another camp supported by Doris Duke for youngsters from the inner New York City. If memory serves that second summer camp was near Three Mile Harbor. Maidstone Country Club of East Hampton again, if memory serves, also maintained a group of WP's.
The boats were all wood, masts were square/rectangular Sitka Spruce with no sail track on some just a milled groove to accept the roped luff of the sail others had conventional bronze sail track, no head sail, a 'barn door rudder, centerboard out of Oak with a lead insert ala Bob Smalser. ;)

Very forgiving craft for youngsters to learn to sail in. Not fancy, no seats, just slatted floor boards resting on the ribs and floors.
3 stay wires made up the standing rigging. Cotton Sails with 3 batten pockets and that was it.

To paraphrase the 'Gypsy' in For Whom The Bell Tolls...someday I'm going to build me a Wood Pussy and, you can believe that or not! :D

[ 02-10-2005, 02:01 PM: Message edited by: Dave Fleming ]

[Bob Smalser]

Originally posted by Dave Fleming:
....centerboard out of Oak with a lead insert ala Bob Smalser. ;)

:D Traditional drifted oak centerboards?

We do traditional drifted-oak centerboards. (...with some epoxy cheating, tho. ;) )

http://pic3.picturetrail.com/VOL12/1104763/6583947/84760753.jpg

http://pic3.picturetrail.com/VOL12/1104763/6583947/84771679.jpg

http://pic3.picturetrail.com/VOL12/1104763/6583947/84771686.jpg

[ 02-09-2005, 08:44 PM: Message edited by: Bob Smalser ]

[ssor]

Nice work!!

[ssor]

Nice work!!