Tapping weight bolts

Bumlak

AzB Silver Member
Silver Member
So I was experimenting with tapping my own weight bolts using a 5/16-18 cap head and tapping to a 8/32". The problem I ran into is that once the bolt is drilled, it seems to want to turn in the headstock when I start to tap it. I guess I could just thread a nut on it and lock that down but I was just curious how it's actually SUPPOSED to be done.
 
Normally for holding threaded rod/ bolts/threaded things, making a split bush of that thread form works very well. It then clamps on the thread form itself, not the crests of the thread form. You could use a nut, but generally nuts are made to the loose side of the thread tolerance and often are not concentric to the hex of the nut itself.
 
Normally for holding threaded rod/ bolts/threaded things, making a split bush of that thread form works very well. It then clamps on the thread form itself, not the crests of the thread form. You could use a nut, but generally nuts are made to the loose side of the thread tolerance and often are not concentric to the hex of the nut itself.

So Neil,

Basically, make a delrin collet, thread it and then split it?

Erich
 
So I was experimenting with tapping my own weight bolts using a 5/16-18 cap head and tapping to a 8/32". The problem I ran into is that once the bolt is drilled, it seems to want to turn in the headstock when I start to tap it. I guess I could just thread a nut on it and lock that down but I was just curious how it's actually SUPPOSED to be done.

It becomes just another futile effort in mental masturbation............ just buy them......... move on to a better use of your time..................

Kim
 
Are you trying to tap these weight bolts with them chucked up in a Hightower lathe? The aluminum jaws won't be much of a friend if that is the case.

The split nut is your best move. Tommy D.
 
Back
Top