evening all, Im getting to the stage where I can actually use my mill (electricity arrives at the weekend :) so my thoughts turn to the drawbar. The mill is int 40 taper, and the drawbar that was in it is marked unc. needless to say my collet chucks are M16... (its never simple). My guess is that as the taper isnt a driving taper, there are two big dogs for the drive the drawbar only has to hold the tooling in place, and not with a large amount of force? I have some M12 studding (the drawbar nut is M12) and a couple of M16 bolts. thus the correct threads are already done :) but on 2 separate bits :( My plan is to unite these parts and hey presto drawbar. As I see it I can either drill and tap the M16 bolt for M12, or drill and cross drill and then pin the M12 studding in, or possibly drill through and rivet/weld over the end. Obviously the threading option is strongest, but also the most PITA, esp as I dont have an M12 tap, but would the cross pinning (quicker?) be strong enough? Or, where do I get a drawbar that doesnt cost an arm and a leg, which is M12 on 1 end, M16 on the other, and of the correct length for a TOS mill?
thoughts and opinions please