Keel Material

[lewisboats]

Looking for opinions on what I should make the keel out of on the boat I am building. First and foremost...the boat will be lucky to last 5 years. For everyone who wants to say something about it lasting longer...It is a proof of concept build (I am also developing plans and building method out of the build), it isn't being built out of materials that will last (too long), I don't want it hanging around all that long taking up much needed (to built other boats) space. It might even end up as mulch before it hits 5 if I don't like it or find something I just gotta build or I need to build something else to develop plans.

My options for keel material are limited in the middle of corn country. I have scoped out mahogany (1x6"x8' =$30 + lots of laminating and seams), 1x12x8 Ash ($50 and some laminating) and 5/4 Red Oak (1" true x 12" x 8' = $45/board) which would only require routing out for the swing part of the keel (3/8-1/2" steel) and is nice and heavy in itself. If I used PU glue to glue the faces together I could get the keel out of 2 planks of the 5/4, whereas I would need 3 or more of the other stuff. I know red oak has nothing on the white for rot resistance, but do you think it might last for 4-5 years if properly sealed and painted?

Steve Lewis

The boat in question is here...top picture:

http://www.angelfire.com/ego/lewisboatworks/html/GuppyIIbuildnav.htm

[capt jake]

Link gives me and error.

No to the Red Oak, it will rot badly.

Yes to the Mahogany, but it is costly.

Not sure on the Ash, I am thinking it rots also, but I can't remember for sure. Ash is somewhat in the same family as Oak.

[lewisboats]

link is fixed. Thx for the reply

Steve

[Dave R1]

Steve, could you get your hands on some yellow poplar (tulip poplar)? It's easy to work, easy to get in large, clear pieces and not too expensive. If it is painted it'll last longer than 5 years but that's ok too.

Or you ought to be able to get your hands on some cottonwood. That probably won't last longer than 5 years in a boat that you'd leave out in the rain. I think it can be a bit stringy but isn't all that hard to work.

What did you use on that little boat you brought to the messabout in June?

[lewisboats]

which one?? the ScoutCanu had plywood for the skeg, and the other one didn't have anything.

[lewisboats]

the ScoutCanu had plywood for the skeg' date=' other one [/quote']

Then again, many a Centerboard and Daggerboard has been made of plywood, I suppose the keel could be too. I don't much need massive strength and the edge grain would be well protected with a couple of layers of cloth. I already have some nice mahogany (luan) 3/4" to work with (the transom of Fisher10 is this stuff, and it has lasted nicely)

Steve.

PS: this is a trailer sailer and will most likely see maybe 50 to 100 hrs of water time in it's lifetime.

[Charlie Jones]

so for a short lived boat what's wrong with plain old pine? Of course, good hard yellow pine might out last the 5 years by a factor of 10, but I'm talking lumberyard stuff, well sealed.

Glue a couple of 2 x 6s together.

[lewisboats]

Good Point :shock: :roll:

Steve

[PAR]

Most Lowes/Depot stores sell 5/4's Douglas fur deck. The same store will also have select framing stock of yellow pine. The Douglas fir will be straighter grained and have less imperfections, but can't compete with the cost of select 2 by stock.

[Guest Oyster]

Pine is just becoming too unstable, and has for a very long time, unless you are able to pick quarter sawn stock, which is almost impossible. The narrow stuff is just not possible to saw like that, so you need to buy wide stuff, in most cases and use off the sides of the boards. Pine just twists and warps too much. The movement can ruin your complete project. my.02 worth

[Howard]

Maybe I missed it but what size does this lumber need to be? Do you plan to glue up 1x stock side by side like they do the Weekender keels or is this a stack lamination? The bottom of the keel looks like it might work with two 5/4 boards, but not with that wider section at the top.

How long, how wide, how thick, how many?

[John Weigandt]

On my weekender I found some doug fir 2x12 lumber at a local yard. I picked my lot, and had them planed down to the 1x thickness needed for the lamination. (3/4 inch actual)

The keel is not glassed just epoxy coated and painted and the boat is now about 8 years old.

the planing probably cost me 15 bucks for the boards, and the guy probably had a tear in his eye as he did it, but it gave me some relatively stable relatively clear stock..

[lewisboats]

It should run about 8 ft long, about 2" thick (the drawing is just that, looks good but will probably only be faired into the hull a little), and about 12" wide/deep maybe a bit less. I am leaning towards two 3/4" ply slabs with a 1/2" piece in the middle, then I could use a 3/8"-1/2" plate for the fin.

Steve

[Howard]

Plywood might be a good choice for your keel and you could glue a keel strip of something like yellow pine onto the bottom to seal it up. I wouldn't leave the edges exposed, even with glass. You can get clear yellow pine lumber at a lot of lumber yards. Ask for porch boards or what they call car siding. Plane the tongue and groove off and your piece should still be wide enough. Cover it all with Xynole and epoxy and you might be surprised how long it will last. Inside the trunk too.

Plywood could be used to test a fin design, but may not last long. It doesn't handle the side load flexing. Better to rip some strips of western red cedar or more yellow pine and laminate up a board.

[lewisboats]

Thanks... The fin is going to be 1/2" steel plate so there shouldn't be ANY problems with side loading... :wink:

Steve