I bought a Bison backplate and 6 jaw chuck for my Myford lathe. The Bison back plate has burrs on it and and will not thread onto my spindle. I even tried a second one and it has the same problem.
Interesting fact is that the backplate will thread onto the spindle if I start the chuck side. So I could screw it onto the spindle and clean up the threads. I have done this before but it is such a pain and the consequence or a mistake is screwing up a 100 dollar backplate. Any chance of finding (or borrowing) a tap to clean up the threads. Another question: Will the tap produce a thread good enough for mounting a precision chuck?
chuck