CNC cutting internal threads - GIF

[Altair]

CNC cutting internal threads.




Previously:

External thread cutting - GIF
Thread rolling a bolt - GIF
Machining a multi-start thread - video
Threading a large shaft - GIF
Dual-threaded rod - GIF

[Elizabeth Greene]

I know this as "Threadmilling".

[marksbug]

just milling around in my new threads....
we used a tap, well I thinks it was a tap made for doing this, not what you see hear.I presume it was varring size od and every thread got multiple cuts.( back in the 90's when I was doing cnc machining)

[Elizabeth Greene]

( back in the 90's when I was doing cnc machining)

They have indexable insert tooling for it now; It seems like they have them for everything. If you have a one-off or oddball thread you can use a single cutter like this, or if you want to machine faster you can use a tool that cuts multiple threads simultaneously. (See: https://www.kennametal.com/us/en/pro...p.1280548.html)

My novice understanding is that the big advantage is it's a lot easer to get one of these tools if it breaks vs. burning out a busted tap. I don't have a tapping head or a spindle smart enough to work without it, so that's a factor too.

[marksbug]

the taps were not std type taps, the table went ossolated around the spining tap as it raised quickley. not a regular tapping opp,wehre your screweing the tap in then out. so not many got broken...I dont remember any getting broken. the tap was smaller than the hole.