Builders' Forum Archives
Re: question on deck glas
Posted by Laszlo on Mar 12, 2006
As Lee says, the hull deck joint on a standard Chessie doesn't require glass to hold it together. However, I built my wife's without the deck nails, so I brought the deck glass down 2 inches onto the hull. This converts the torsion stresses along the diameter of the deck camber (which would try to peel the deck off) into radial shear stresses which the glass fibers can resist very well.
The nails work by converting the torsion to tension which is resisted by the rings on the nail shafts embedded in the sheer clamps. I like the fiberglass solution better because it results in a more even distribution of stress. The nails can act as stress concentrators.
The final thing to keep in mind is that either way works well since it's actually the epoxy/woodflour glue between the deck and the sheer clamps that provides most of the attachment strength. The glass or nails are only backup at best, or construction process artifacts at worst. Using the nails is probably a lot easier for the first time builder, and many people actually like the looks.
The way I avoided that messy wrapover that Lee rightly points out is a problem is by putting a line of packing tape 2 inches below the deck joint. Then when the glass had cured to "green" stage, I ran a razor blade along the hull at the top of the tape and just pulled the tape and excess glass right off. A quick touch up with a scraper gave me a nice neat edge.
In Response to: question on deck glass by Joe Oliver on Mar 10, 2006