I have a bass drum with a stain finish (no covering) that has about a 2-3 inch long crack in the shell from the bearing edge inwards. Due to the fact that a drum shell is basically plywood, although the crack itself is only centimeters wide, a lot of the inner plies have seperated a bit and the entire damaged area is about 1-2 inches wide. To fix it I plan to use a nylon strap ratchet tie down to wrap around the shell to bring the edges of the crack together, then glue it with carpenter's glue and calmp it...Now, here are my questions:

1. How do I clamp a curved surface like that to keep the clamped surface round but still put pressure on the entire crack? Remember, the clamped area is about 2 inches wide. Is there some kind of home made jig ideas anyone could recomend?

2. Since the clamp or clamps would have to be right on the actual crack and there will be some glue seepage, no matter how much I can wipe off with a damp cloth, how do I keep the glue from sticking to the clamps or any jigs I might have to use? This would be a real problem if I used the wooden clamp or wooden jigs I planed on using. Is there some material that I can insert between the jigs and the surface that carpenter's glue won't stick to?

Thanks for your help!

JA

John, March 2007

probably best not to use carpenters glue(pva). a better bet might be either polyurethane (which has gap filling ability if the joint isn't a perfect fit), which is wickedly strong and waterproof but, paradoxically, dries more quickly if the glued surfaces are slightly dampened or, a two part epoxy (WEST[for wet epoxy saturation technique] is a good one, which is a very high quality, marine glue). this particular epoxy is fairly 'runny' and so absorbs well and has a good working time (at least 1 hr).
the advantage of epoxy is also it's ability to cure without being exposed to the air. this allows you to place a polythene mask (any old shopping, carrier bag) between the work and the clamp so that things will release nicely when it's dry.
to get a near perfect clamping system you might create a former by first choosing an area on the shell which is undamaged and then make your former by roughing in a couple of wooden blocks which are big enough to cover the repair area, then clamping them in place with car bondo smeared on the face of the wooden blocks to recreate an exact form which you can clamp onto the area to be repaired. again, since bondo itself is an epoxy material, you will need to place a polythene mask between the drum shell and the former which you are making. once it is made, you apply the glue to the repair and clamp the former onto the shell with C clamps.
the ratchet tie down sounds like it might work but, i would try a dry run first to make sure the it will pull things tight enough. also, i think when you glue up, you should put the 'former' clamp in place but, don't snug it up until you have pulled the shell together with the tie down.
good luck.

adrian roddick, December 2007

rachet straps would do it

dazzlin, May 2007