I know this is an old thread but I believe the I have the same model diving head. I have not been able to find much literature on it due to it's age but it is in pretty good shape considering. That said, I have the same odd 2 1/4 x 4 1/2 spindle threads and the 7" Cushman Chuck has seen better days. Not being familiar with Brown & Sharpe Tapers, it was written here that it uses a B&S #10 dead center but can anyone tell me what size B&S collets it uses? I am guessing it would be B&S #10 taper collets but that is a guess any they do not seem to be available.... Any help, guidance, comments, literature, observations etc. would be most appreciated.
Thank you.
Joe