Interesting Threading Attachment

[John_Dennis]

Interesting threading attachment on craigslist. Overpriced.

How does this work? http://houston.craigslist.org/tls/5419089241.html

Snap-tap attachment for manual lathe. Mounts on any lathe. For threading with no relief. Retracts at within .005 every time without breaking insert. A rare find! Made in Sweden

 

[joshua43214]

expensive...
I saw this thing on YouTube a while ago, looks to be made from scrap

It won't retract the tool, but seems to stop it dead on.

 

[hman]

Im pretty sure that video (and an explanation of the mechanism) was posted on this forum a year or so ago. I recall the OP was a gunsmith, because he mentioned being familiar with triggers and sears. Don't know if the CL ad is for the same thing. They sure don't give a lot of detail, do they?

 

[Billh50]

That video is basically what I did on my HF 7 x 12 for an automatic stop.

 

[John_Dennis]

I could be wrong, but I think this device is somewhat more complicated. I think it moves the cutter out so that no relief cut is made.

 

[Billh50]

The Hardinge Lathes had a threading attachment that mounted off the back side that would automatically raise off the part when stop is set. Been a long long time since I used one. But I seem to remember you could set it to cut deeper each pass for so many passes. But don't quote me on that as memory isn't what it used to be.

 

[chips&more]

This could be it?

 

[joshua43214]

That is a pretty cool tool.

 

[omni_dilletante]

 

[omni_dilletante]

It looks like Model Engineer Issue 4177 includes plans for making your own.

It think it looks very interesting.

Here is a video of a home made version: