Tapping Oil ? For tapping Acme thread in bronze.

[john b]

Regular milk. I also found that the original Tap Magic worked extremely well without a lot of cleanup.

[Ian B]

"Bronze". I've come across all sorts of bronzes over the years, some a dream to machine, others a complete nightmare. If it was hard brass, then simple - do it dry. But bronzes have all sorts of characteristics, you'll get a hint when you drill the stuff before tapping. Does it drill like softish brass, or does it let you get the drill in and then suddenly grab it and seize up solid, leaving you with a workpiece with a permanently embedded drill?

If the latter, maybe get some different bronze...

Ian