[FuriousGeorge]

I'm considering buying the TTS ER16 tension compression tapping head for the purpose of tapping some small (m1.6) holes. Does anyone have experience machine tapping holes so tiny? Would the tension compression head even work on this, or would the spring just strip the threads?

[Freddy Bastard]

you should thread mill thoses holes.

[Don Clement]

I have had very good results with tapping small holes such as 2-56 blind holes shown here using a TTS mounted Procunier 1E reversing tapping head with my Tormach.

Don

Tapping 2-56 on Tormach video by miltons_stuff | Photobucket

[MichaelHenry]

I'm considering buying the TTS ER16 tension compression tapping head for the purpose of tapping some small (m1.6) holes. Does anyone have experience machine tapping holes so tiny? Would the tension compression head even work on this, or would the spring just strip the threads?

Material and tap type will make a difference. I've down hundreds of #4-40 through holes in aluminum with spiral point taps and had nary a problem.

I'm about to do some #3-48 blind holes in aluminum and will be trying a form tap.

Whatever you do, don't just use a standard tap, especially one from the HW store.

Mike

[Steve Seebold]

I would definitly use a form tap. By doing it with a form tap, you should be just fine as long as you don't hit the bottom of the hole.

[Don Clement]

For tapping small blind holes in 6061-T6 Aluminum I use a Balax form tap. The form tap doesn’t cut thread but rather forges the threads and therefore no chips— especially good for blind holes. I have tapped 10s of thousands of 4-40 blind holes in 6061-T6 using the Procuier 1E reversing tapping head, forming tap, and Relton A9 tapping fluid on my Tormach with excellent results. One of the reasons IMO that the Procunier tap head works so well with small taps is the double-cone "cushioned" clutch of the Procunier. Also the Procunier tap head stops within 1/3 rev and there is no need for dwell time. I also know that the 4-40 tapped formed holes work well because I am the one who installs the screw in each hole that I have tapped. I have my own quality control and can tell how well the 4-40 hole was tapped. In my experience the Procunier and Balax form tap make a very strong consistent threaded blind hole as proven by the 10s of thousands of holes that were made with a SS screw installed.

Don

[MichaelHenry]

I would definitly use a form tap. By doing it with a form tap, you should be just fine as long as you don't hit the bottom of the hole.

Thanks - there is plenty of room for a deep hole so bottoming out the tap won't be a problem.

[MichaelHenry]

For tapping small blind holes in 6061-T6 Aluminum I use a Balax form tap. The form tap doesn’t cut thread but rather forges the threads and therefore no chips— especially good for blind holes. I have tapped 10s of thousands of 4-40 blind holes in 6061-T6 using the Procuier 1E reversing tapping head, forming tap, and Relton A9 tapping fluid on my Tormach with excellent results. One of the reasons IMO that the Procunier tap head works so well with small taps is the double-cone "cushioned" clutch of the Procunier. Also the Procunier tap head stops within 1/3 rev and there is no need for dwell time. I also know that the 4-40 tapped formed holes work well because I am the one who installs the screw in each hole that I have tapped. I have my own quality control and can tell how well the 4-40 hole was tapped. In my experience the Procunier and Balax form tap make a very strong consistent threaded blind hole as proven by the 10s of thousands of holes that were made with a SS screw installed.

Don

I use a Procunier 1E on my manual mill and like it there, but the Tormach tension-compression head is more convenient for me on the Tormach and has worked well so far for through holes with gun taps. Hopefully, it won't have any problem with the Morse form taps that Mari Tool sells.

Mike