Automatic Carriage Stop for precise threading.

I have come up with a solution to precision thread cutting without an undercut and making cuts within a few thou of a shoulder, without fear of wrecking the shoulder. My invention automatically releases the half-nut, thereby stopping the carriage. I built this automatic carraige stop several years ago and use it in my custom rifle shop everyday. I am selling a complete blueprint package including pictures for $100.00 per set. Will cost you less than $50.00 in materials to build. I have available a free VCR tape showing the "AutoStop" in operation. If you would like a copy of the video email your address to me & I'll get a tape in the mail for you. Email with any questions or call 540-890-8649. Thanks.


[This message has been edited by groundhoginc (edited 03-27-2004).]

Does it back out the threading tool also?

GGaskill, my thoughts exactly. Personally, I set up a 2" travel dial indicator on the ways and let it ride against the saddle. Just watch the dial, and when the time is right, back out and disengage. I've never hit the shoulder, and no relief cut.

Is this one anything like the Hardinge? That is a dream to use and the slide on the compound means you never have to back the cross slide out. Anyone have any idea which is stronger,pulling out at the end of the threads, creating a moment, or a full radius thread undercut? With a Blackhawk in fifty cal it gets a wee bit thin. Any thoughts or should I increase thread size? Good Luck and God Bless

im with RWS here ive used a travel indicator for over 30 yrs to thread up to a shoulder and can disengage the halfnuts and retract the cross slide w/in a couple thou.
this is a typical apprentice practice...jim

Jim
At 800 RPM on wee little parts the Hardinge will stop within .003 and with people walking up behind you and asking" how's it going, I loved it. And as to the people, a rolled up newspaper worked well, or the promise of some bubble wrap if they whistled when they walked up. Just my thoughts,God Bless.

while i really like a Hardinge to it still doesnt retract itself at the end of the thread.
i, if possible, use a radius thats at least 1 1/2 times the pitch to end the thread in.
works great for windage screws...jim

Jim,
The fifty in a five shot Blackhawk is still a lower pressure round, but it is still nice to try to get as much in your favor as possible. Off setting the barrel is one way to get some meat in a six shot fifty, really fifty special. The current project is a 41 special in a single six for a cohort. 270gr bullet at any speed is a tool. Anyway, a full radius relief seems to "balance" the load on the barrel. Thanks for the thought. Obscure, to me at least: when firing the 240MM howitzer, drifts left north of the equator, to the right south of it. Now I wonder if it increases farther from the equator? Good Luck and God Bless