I just recently purchased the set-o-matic double tom holder for my 1970s white diamond Slingerland kit. It fits fine; however, on the bass where the stem of the set-o-matic goes into the bass drum, there is a non-threaded hole used to keep the the stem from moving (At least that is what I think it would be for). I can't find the piece for this, and I don't understand how it tightens without there being any threading for the bolt (or whatever) to hold onto. If anyone could explain this piece to me and, perhaps suggest what could be used in place of the original bolt, I'd really appreciate it.
Thanks,
Brandon