Internal tool for external threads?

Without getting into a debate about the best single point threading methods, my question is this:
Will using a right hand internal lay down threading tool, with full profile inserts, cut correct external threads, when used on the back of the part, with the lathe running in reverse, feeding left to right?
 
Without getting into a debate about the best single point threading methods, my question is this:
Will using a right hand internal lay down threading tool, with full profile inserts, cut correct external threads, when used on the back of the part, with the lathe running in reverse, feeding left to right?
Yes
There are some differences between the internal/external thread forms but these are marginal, if the parts are being made for a Customer that has the capacity to measure these features then the answer is no.
If the Customer can not or does not measure at that degree of accuracy have at it, the parts are unlikely to return with a red tag and 5 pages of printed Non Compliance data.
Good luck.

I have done this in the past, do not tell anyone (-:
 
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Seems to me, the tool in the picture above was made to cut on it's lower left face. If cutting as above, it's cutting on it's lower right face. It doesn't have the correct relief on that cutting edge. But Yeah, it'll work.
 
Seems to me, the tool in the picture above was made to cut on it's lower left face. If cutting as above, it's cutting on it's lower right face. It doesn't have the correct relief on that cutting edge. But Yeah, it'll work.
Not a threading tool in this case just a triangle insert boring bar, it is the only picture that I have of using a boring tool for OD turning on the back side of a part.

The programming requires all X axis positions to be -0.000 moves in this case, I probably could have set the tool offset on the back side of the part but this often opens another can of worms with these lathes.

Recently I tried to program a gang tool holder in conversational mode, this machine simply would not run this way, had to FingerCam the entire operation line by line. This is cumbersome and time consuming at best.
 
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Without getting into a debate about the best single point threading methods, my question is this:
Will using a right hand internal lay down threading tool, with full profile inserts, cut correct external threads, when used on the back of the part, with the lathe running in reverse, feeding left to right?

Yes ! I do that all the time.

18-09-2018-2.JPG
 
the question would be "does the cutting edge have enough relief to clear the flank of the thread". If use, you're golden. If no, the flank of the thread will push the tool out of the cut and you'll get a crappy finish.
 
Hi Guys,

That picture above is me cutting a 4-48 thread,

26-09-2018-011.JPG
This is a M30 X 1.25 cut in the same way, lathe in reverse and away from the chuck.
 
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