Need help with bumpers

[M. Mellott]

Last year, with 4 seperate bumpers, we used 1/4-20 carriage bolts (large, smooth button head backed by a square shank before the threads begin) through a thru-hole in the spec-size plywood--4 bolts for the longer sides, 2 for the front/back. The square shank bites into the plywood and keeps the bolt from turning while being tightened. The bolts ran through holes drilled into the side frame members (1.5"x1.5" welded aluminum tubing frame) and fastened by wing nuts that are hand tightened (i.e. no tools). We used lexan panels for side shielding on the base frame held on by velcro, which allowed us to rip off the panels and have easy access to the wing nuts for quick removal of the bumpers. We usually checked between matched to make sure none of the wing nuts loosened as part of our pre-match checklist. There were some doubters at first on the wing nuts, thinking they would loosen and fall off during a match, but we didn't loose a bumper (or a nut) all season. The only issue we had was placing the bumpers back on and getting 4 bolts through the blind holes on the inside of the frame rail--takes a little practie to do it quickly.