Adapting a dial thread gauge Metric Vs imperial

Hi ya Vasco,
Sorry I was a bit slow getting to this.
Hi Phill, If you could try it would be great. Please let me know.
The thread chasing dial will work on any thread, provided you only use the one same mark on each engagement of the 1/2 nuts. The leadscrew/carriage relationship does not care whether you are machining a 3TPI acme, 14TPI whitworth, or 1.0 mm, (which in effect is just a 25.4TPI) anyway.
--->JT The point of the exercise is to avoid having to wait for the carriage to travel back to the starting point to recommence the next pass, not to reduce nut wear. Also something that is a pain to do if you dont have reverse on your lathe. Cranking the drive pulley backwards gets real old real fast.

Cheers Phil
 
Phil, just out of curiosity, did you do this experiment on your lathe? If so, please remind me of what kind of lathe you ran it on. I've not done the Imperial on a Metric lathe thing before, but on an Imperial setup Mazak, even using the same number on the chasing dial, it never tracked the Metric thread the same way twice.
 
Tony,
I have a change gear Hercus 9". It is an imperial lathe, and has had some mods done to it over the years, (some by me, others not by me). My chasing dial is not original (I dont think). Yes I did run it on my lathe. Although I only scored the thread on some ally rod, disengaged, wound back, re-engaged, and followed the previous score exactly. No compound movement. I didnt complete the full thread. Now you got me thinking maybe I was just lucky :thinking:

Cheers Phil
 
No Phil, I doubt it. I was just working over in my mind how the Mazak could have been geared differently. Of course, Yamazaki lathes are Japanese built, so I would presume they are natively Metric, and those sent to Imperial-land are geared to cut Imperial threads. But then, it's been quite a while since I scrapped....I mean re-worked those parts for Bell Helicopter. I took 2 or 3 passes before I saw it was not re-tracing the thread. Ended up doing the forward and reserve thing to cut the parts.

There was probably more to making that lathe properly cut Metric than I knew at the time.
 
No Phil, I doubt it. .....There was probably more to making that lathe properly cut Metric than I knew at the time.

Nontheless Tony I think I will go back and redo that test, but actually cut a full thread......Dont want to be putting wrong info out there....

cheers Phil
 
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