> I have decided to build a box beam type stronge back for my
> Guillemot.Three things I would like to know are: 1 how long should the
> beam be.2 how do I attach the end forms to a box beam.3 is there any
> reason why Icould'nt fill the gap inthe center of the beam with plywood to
> make it solid all the way through.

> THANK YOU IN ADVANCE AND HAPPY NEW TO ALL J.D.

The boat itself it 17', the end forms have cutout section for the tapered end of the form to fit, so if you use 1/2 material for the forms, the beam ends up 14' 11" tip to tip. Your length may differ depending on how your notch your end forms.

I used a bunch of quarter-round trim pieces and hot glue to position and hold the stem forms to the boxbeam. In a few places where space allowed, I used drywall screws and scrap wood blocks.

I wish I would have either made a solid boxbeam, or used 3/4" plywood. I used 1/2" plywood, and hollow, the boxbeam wasn't too rigid. I tried to retrofit it by inserting plywood fill in the center, but that had limited effect. Build the boxbeam as solid as you can, especially if you intend to make more than one boat. (who can stop at just one?)