Posted by Rocky Bivens on March 06, 2002 at 07:22:46:
In Reply to: ignorant about fiberglass techniques posted by js on March 05, 2002 at 09:29:02:
Joe, in a former life I attempted to make a living as a sculptor. In that regard, I had occasion to work with both polyester and eposy resins with fibreglass. Both are hazardous materials and the work area *must* be well vented.
I would approach this by making both an outer and inner mould. Of course the outer mould would not have to be very accurate, simply adequate to house the horn with a relatively even distance (about 4-5 inches, I would guess) from the outside to the inside (where the horn sits). If I wanted it smooth and presentable, I'd make this mould (the outer one) with wire mesh coated with some moulding material (like plaster or concrete). If I didn't care about the looks, I'd just coat it with plastic sheet. Once made, I'd use resin and fibreglass (cut into relatively small pieces) to make the outer shell of the case.
After this, I'd fill in the crevaces of the horn with foam and wrap it with plastic sheeting, trying to get it relatively even. Then use some stiff bailing wire and make "posts" to sit against the inside of the outer shell to hold the horn up an even distance (I'd guess about 3-5 inches) away from the shell.
Finally, I'd use polyurethene foam and spray it into the space formed by the outer shell and the tuba (encased with foam and plastic sheet).
I hope this gives you some ideas. Obviously, it would take some experimenting and probably modification.
Good luck!