Tapping fine over coarse threads
Tapping fine over coarse threads
(OP)
I mistakenly had a hole tapped 4-40 instead of 4-48. Normally this wouldn't be the end of the world. However, ball spring plunger only come in 4-48 in that size. Is there a remedy to this? I've attempted using a helical insert but the material is titanium and it just tore up the tap.





RE: Tapping fine over coarse threads
RE: Tapping fine over coarse threads
RE: Tapping fine over coarse threads
Double-tapping will not work. You will either be tapping "air" (the gaps between the original threads) or cutting and stretching criss-cross patterns through what little metal remains in the original thread.
RE: Tapping fine over coarse threads
RE: Tapping fine over coarse threads
And, for a nbr 4 tap in darn near anything, look also for the carbon-based-control-system-error between tap handle and floor.
RE: Tapping fine over coarse threads
It hurts my feelings when you talk about me that way. You know how sensitive I am.
Dan T
RE: Tapping fine over coarse threads
http://www.cimindustry.com/article/tooling/tips-fo...