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bob ward
12th Jul 2020, 03:07 AM
I'm making cuphead bolts from 1" round and needed a method of indexing the stock while I milled the square shanks, 1" is too big for the ER32 collets and collet blocks that I have.
I turned the outboard end of the stock to 20mm, attached an ER32 collet block and propped it at the right height for the vice, in this case a piece of 1.25" hex was just right.

387548

387549

bob ward
26th Jul 2020, 09:14 PM
Whenever I move away for whatever reason from conventional RH single point threading to threading with the tool on the other side of the work, and/or upside down and/or threading away from the headstock I'm never sure which hand thread I'm going to end up with.
From a recent post on PM came this easy to remember method of knowing the answer.

If the spindle and lead screw are turning in the same direction you are cutting a RH thread, if they are turning in opposite directions you are cutting a LH thread.