C clamp glue up (what's the secret?)

[tim-flood]

I have used rubber bands cut from truck innertubes.  and they work everywhere around the shop too and are free from tire places and good big sissors.  put lots on the mold and then heat it up some will give up but with lots it still works just fine and the pressure is still there in the oven if something shrinks

[Tom Leemans]

I've only glued up bamboo backed bows. Never done glass, but I use c-clamps. I bought some rubber from McMaster Carr (they're on the web)and cut strips from it. You can probably buy a roll of it in the size you want also. They're good folks to deal with. Anyway, I lay the rubber against the bow surface, then top the rubber with a wooden pressure strip, about 3/16" thick, ripped from a clean 2X4. The wood sucks up the dents from the clamps and spreads pressure to the rubber. The rubber spreads the pressure out evenly. Tighten the clamps with your thumb and two fingers, and you shouldn't overtighten. When it feels like it wants to stop, then stop! Don't crank down. I clamp approximately every 2". Throw away the wooden strip or cut it up for some other use when done.

That said, if I were to crank out a bunch of glass bows, I'd use an air hose.