> I am just beginning construction of an expedition single. In regards to
> the wood used for the forms, is it necessary to use plywood, or can I get
> by using chipboard as the form wood material?

I use particle board for forms. The cheapest I can find.

Staples don't get as good a grip on chipboard as they do on plywood. If you are using the longest staples you can get, and drive them in straight, you should have few problems. If your strips are fatter (thicker) than 1/4 inch you might have a few more problems, and if they are 3/16 or thinner you might have fewer problems -- all becasue of how much of the staple would actually seat in the edge of the particle board or chipboard.

In areas where the strips are flexed a lot the staples may not work. That is not a real problem. You can use 1 inch wire brads to hold the strips in these areas. A box of brads should be under a dollar -- a big savings over using plywood.

There are several ideas for assembly that do not use staples: clamps, straps, wedges, etc. With all of these particle board or chipboard works dandy.

Another possibility is to use lots of drywall screws driven into scraps of wood, as mini clamps to hold the strips in place while the glue sets. The screw goes through the wood scrap and on into the edge of the form. It is alongside of, and not through the woodstrip, so there is no hole in the strip. Tightening the screw causes the wood scrap to pinch the strip like a clamp, securing it. Back out, and reuse the wood scraps and screws. An electric screwdriver makes this a fast job. If you plan to reuse the forms a lot, all those holes will get to be a mess after 4 or 5 boats, though, so I wouldnt recommend this for a production shop.

Hope this helps

Paul G. Jacobson