I applaud your ambition to build, but it seems like reinventing the wheel. There are several options, some of which you've noted. Martin uses HPL (high pressure laminate, often referred to colloquially as Formica). Cheap imports use all laminated tops along with the laminated bodies. The ultimate is a composite material like carbon fiber or eKoa, but it doesn't come cheaply. I suspect that most fiberglass lay-ups would have too much resin content that would heavily dampen any vibrations. CF is usually vacuum bagged during curing and uses "pre-preg" (pre-impregnated cloth) to achieve an absolute minimum of resin.
Your guitar won't necessarily crack just from getting cold. A nitrocellulose finish will crack (cold-checking) if thoroughly cold-soaked and then warmed quickly. Some of my guitars have traveled all day in the unheated back of a truck at -40°F between Anchorage and Fairbanks. As long as there was a dampened sponge in the case to provide some moisture as it was allowed to warm slowly, I did not have any problems with cracking.
|