I have a set of the B&D air retracts (tri-gear). They work well for the most part, but I can't tighten up on one of the set screws. It's the screw that holds the strut into the base of the plastic housing. If I over tighten, the retract on that side won't come down. The allen screw does not go all the way through as far as I can tell, so I am guessing that it is deforming the plastic just enough to pinch the gear. It's a little annoying because the strut keeps turning because I can't tighten down on the screw. Any ideas?