[Don Clement]

I use a Procunier reversing tapping head for small holes. The Procunier works especially well on blind holes using a cushioned double-cone clutch that stops within 1/3 rev. For larger holes and external threads I use thread milling. Here is an example of a 60mm-0.75mm external thread that was thread milled on my Tormach.

Don

[Moggot]

I use a Procunier reversing tapping head for small holes. The Procunier works especially well on blind holes using a cushioned double-cone clutch that stops within 1/3 rev...

Don

I'm interested in any other thoughts you have on the Procunier. I produce a part on my 1100 that includes a 0-80 threaded hole, arrayed several dozen at a time. Currently I hand tap each one. Doing this operation on the mill would be, for obvious reasons, awesome.

From what I gather a tap that small really has to be done with the reversing head. Justifying the investment isn't a slam dunk with the bean counters, though, and I need to know that it's going to be a net time and effort saver before I spend the good will with my boss by begging for it. Have you ever used it for very small holes such as a 0-80? I realize it's 'rated' for that size, but...

[Don Clement]

The Procunier is the perfect reversing tapping head for tapping small holes on my Tormach. I have tapped 10s of thousands of 4-40 blind holes using the Procunier. Here is an example of tapping 2-56 blind holes on my Tormach.
Tapping 2-56 On Tormach Video by miltons_stuff | Photobucket

Don

[FuriousGeorge]

From what I gather a tap that small really has to be done with the reversing head. Justifying the investment isn't a slam dunk with the bean counters, though, and I need to know that it's going to be a net time and effort saver before I spend the good will with my boss by begging for it. Have you ever used it for very small holes such as a 0-80? I realize it's 'rated' for that size, but...

I use a tapmatic tapping head with great results for #2 and #1 holes. I've never tried a 0-80, but I'm sure it could do it. You can find them used on ebay (Tapmatic 30 TC DC Reversible Tapping Attachment Free Shipping | eBay) for around 200 dollars, so it won't break the bank. What material are you tapping? This one maxes out at 2000 RPM which is a little slow for a 0-80, but I'm sure you could get away with it. The head that Tormach sells is loads better and maxes out at 3000 RPM; I would be shocked if you couldn't tap the holes you need with that.

[fizzissist]

I've tapped hundreds of blind 0-80 holes in 304SS with a Tapmatic. The Procunier is also an excellent tool. Used and maintained properly they're both great tools.