Thread forming

[crayner]

I have a job where I need to produce several thousand externally threaded 304SS expansion rods RH thread on one end, LH on the other. I'm wondering how to go about this properly. I have a great high-speed mill, a crappy manual lathe... wondering if there is something akin to a tapmatic that I can mount on the lathe... I've looked at geometric die heads, but they all seem to be specific to screw machines/automatics... anyone?

[lakeside]

Tapmatic Use The Idea That The Part Is Held And The Tap Is Spinning If You’re Looking At Doing It In A Lathe A Chaser Head Is Probable You’re Best Bet This Can Be Found Used On The Internet

[jderou]

Dont know how long the thread is, but you could do an external thread mill routine in the cnc. I would think that would be way too slow for several thousand parts, though.

[Rustybolt]

Yeah there is. Procunier makes a tapping head that takes acorn dies.

[CNC Pro]

I just purchased an automatic lathe. I’ve been looking at “box type” tooling. I wonder if this might be an option to run in a tailstock, as some are available with 5/8” diameter shanks? One consideration though is the length of the thread; as box tools are limited in this respect.

[Rustybolt]

"automatic lathe" you mean cnc, or automatic screw machine?

To answer your question; yes they make them in a self releasing style just for that purpose. 5/8 is the smallest I believe.

[CNC Pro]

Hey Rustybolt,
They call it an automatic “capstan” lathe. From what I’ve seen, automatic screw machines have multiple spindles. This machine has one spindle, with a 6-station turret, front and rear cross slides, and an over the spindle part off slide. It’s currently set up with pneumatic collet closer and pneumatic bar feed, but it’s also equipped with controls for a 6” pneumatic chuck (I have to order a chuck).