Here's another scribing test.
Attached are two pictures of a threading scribe test which was done at 115rpm and 60
( 0.0001" deep passes ). I used a 30 degree angle so it was radialy cutting thus no Z offsets in the Gcode. Picture 1 shows finished scribing and there was a definite improvement. Picture 2 shows
the end of the passes and the total width of all the cuts was cut in half as compared to the same at
402 rpm and there are five distinct cuts.
Now i watched each cut under the microscope since i can see the actual tip point and what material is being removed. For the first 20 passes it tracked the first pass. Then there was a slight shift at pass # 30 about 0.002" increasing the lead. Then at pass #46 the cuts started oscillating, such the one would be on the first pass line, then maybe the middle of the width, and finaly further down the lead. Pass #53 opened up the width some 1 or 2 thou ( lead increase ) and then pass #54 opened the width up around 1 thou ( lead decrease ). Passes after that kind of tracked the middle of the of all the passes.
So it seems that the sensor is not constantly stable, maybe.......since that's what the o'scope's telling me, but i don't trust it. But then it could be the PC or combination of both.
If anything, i can say it dosen't take much to screw up a thread.
And for those following this, when you post and ask a threading question, and maybe you get so many different thoughts on the matter, some generalized comment, now you know there may not be a simple answer to a system of mechanical, electrical and software all trying to work in harmony!
RICH