Having a bit of a problem with my air pump. Its a Blackburn floor pump. The issue is the end that goes on the schrader tire vale is sooo snug. I blame it for a popped tube (at home thank goodness!) that I just had to replace. The rim tape is in good shape and I used some emery cloth to smooth down the outside edge of the hole in the wheel. I really don't think that spot caused the cut in the stem, but maybe so.

Is a threaded chuck available, and from where? Just started looking today. Milton and Schraders websites were no help.

Considered some sort of lube, but the threads on the stem seem to keep that from working on a repeatable basis. I have not tried anti-seize.

What am I missing?