Buck, your knocker should make contact with
the end of the crankshaft putting the impact of
the blows there. If it doesn’t then your putting
the impact on the crankshaft threads which
could distort them. If your knocker is in fact
making contact with the end of the crankshaft
ignore this response.
Tubs.
Tubs, I understand what you’re saying, but there’s no practical
way to tap threads to the very bottom of a bind hole, even with
a bottoming tap. I did tighten the knocker nice and snug until
it ran out of threads, so it was nice and tight on the threads.
I actually thought about looking for a ball bearing to sit atop
of the crankshaft, then tighten down the nut, but then I was
wondering if it might flare out the top threads and jamb my
knocker.
I possibly could chuck the knocker in the lathe, and try to
bore out the top of the hole above the threads, using a boring
bar, so the knocker would screw on all the way, hitting the top of the crankshaft.
Thoughts?
Prepare to be boarded!