Tapping 4-40 on CNC

[petriej]

I have posted regarding this subject before, but I would like to know what tool holder shops are using to form tap 4-40 in 6061. I have done quite a bit of research, but can't pinpoint which holder would be the best for this application. Or should I run solid with a collet? My machine is older, but does have the tapping autocycle.

Any help is greatly appreciated.

Thank you

[djr76]

I use a rigid tap holder with quick change tap adapters for each size of tap. Any collet should work as well though.

[star-turn]

Depending on how used your m/c is and whether it supports rigid tapping i would go for a 'floating' holder - one that lets the tap either pull out or compress - you will have more control over getting the tap to cut without snapping.

PCM do a nice version that fits directly into an ER25 collet holder.

ST