balsa skimboard project

I plan on making a balsa skimboard from layered sheets of 1/8th inch balsawood, kinda glued together somehow. The sheets im using are gunna be 3 ft long by six inches wide, and the dimensions I want on the board are 50"x18 1/2x3/4. If anyone can help me with this that would be great, I kinda have no idea of what im getting into working with balsa.

Should I use thicker sheets? Otherwise thats the longest and widest I can get.

How should I glass it? Would 3x2 four ounce work and how should I do the laps?

Do I need to use a stringer or will the glass job hold it togeter?

How should I glue together the individual peices, should I use something like elmers and try to make a big peice and shape that, or try and do some sort of composite thing with a layer of glass sandwitched somewhere in there?

I would try a surfboard, but I think with the size peices im using it would be extremeley hard, and im pressed for money (each of these is like a few bucks each and im guessing im going to need alot of them.)

If anyone could give me any hints or advice about this it would be great, thanks!

If they’re only 1/8" thick and you want final thickness of 3/4" (which is a little thick for a skim), you definitely want something else in the core. You could find a piece of core-cell or divinycell like Bert uses, or use a piece of plywood, or experiment with some other kind of foam. If you use foam, bend in the little bit of nose rocker you want as you laminate the balsa to the foam, probably doing the top first with some epoxy resin and putting it on 2 sawhorses with a brick in between for the bend.

If you go with plywood, here’s how we used to make 'em in high school: Put the cut out plywood ‘blank’ in a tub of water, kids pool etc. weighed down with bricks for 2 days. Then get it out and put it rightside-up on 2 sawhorses, close together. Put a couple of bricks on top until the bend looks right. Put it in the sun so the top dries faster than the bottom, because that will help set the curve. When we wanted them thick & heavy, we then laid them up top & bottom with 4 oz glass. If we wanted them light, Marine varnish was all it took. Either way, 1/2" plywood was the material. 1/2" plywood with a balsa skin would be plenty strong & beautiful. But you’d have to make sure it got really dry before you glued on the balsa. For wood to wood, don’t use Elmers, use yellow glue like Titebond.

Now, I’d probably figure out some kind of foam. Even if its just 1/2" EPS from Home Depot…

well I was going to try 3/4 because I was going to try and get some float in. If I epoxyed just a balsa shell over some eps, that could be glassed with poly then afterwards right? If the poly couldn’t get in? Like if I shaped an eps blank, and just covered it with a shell of balsa, would that work?

Sorry I have so many questions, I just don’t want to screw this up, I hope someone has done something like this before.

How about end grain balsa core with an epoxy glass job? Usually used in boat construction. Comes in 2 x 4 foot sheets in various thicknesses. Google search on all four words: end grain balsa core. Here’s one of John Galera’s paipos using end grain balsa core.

interesting… I tried looking it up and only found stuff that was cut on one side, and glassed on the other to let it be flexible, and its the only thing I can find. If I did use this, how would I go about glassig the other side? Im guessing don’t use it at all, but what if I did like benny said and just put a shell around some other foam, could I put a shel on the other side of it somehow?

Those loose blocks glued to a thin, flexible fiberglass scrim is the same stuff used in the picture Poobah posted. It is also possible to get end-gran balsa in plain sheets where all of the blocks are glued together, but it isn’t used as often so usually then you have to buy it by the case instead of one sheet at a time.

Both kinds need to be fiber-glassed on both sides to make them usefull. The best way to do that is to use a rocker table which is basically just a mold where the surface has the same curve as the rocker you want in the finished board. It’s pretty eaasy to make a rocker table, just use a good smooth sheet of plywood or mdf for the top surface and build a scrap lumber frame on the bottom to make the top surface bend to the shape you want. Then cover it with something that will keep your resin from sticking. If you are using epoxy, a piece of 2 mil or thicker flexible plastic sheeting works fine for that.

A rocker table is the way to go if you decide to use foam too. Skim boards are too thin for any of the core materials to hold their shape - untill after you glass both sides. So you glass one side, then set it in the rocker table and use weights or better yet a vacuum bag to hold the board in the proper shape untill the resin cures, the do the other side. The scrim-backed blasa is so flexible that you probably won’t need weights, just set it on the table, glass the top, then cut out your shape and glass the bottom and rails.