07-16-2021, 08:30 PM
I started to cut the threads and soon realized they looked like saw tooths. WTF!
I know the gearing is set up right because the scratch pass showed exactly 16TPI. I repeated the attempt on some delrin I had and same problem. Had to be the angle I set the compound to. I had set it to 29.5 degrees but to the incorrect reference. I got bit by this same error when I first turned threads on my 14x40 lathe. Corrected the angle, still 29.5 degrees, and tried cutting on the delrin and perfect threads.
Since I butchered the original part I have to make a new blank and start over.
Ed
I know the gearing is set up right because the scratch pass showed exactly 16TPI. I repeated the attempt on some delrin I had and same problem. Had to be the angle I set the compound to. I had set it to 29.5 degrees but to the incorrect reference. I got bit by this same error when I first turned threads on my 14x40 lathe. Corrected the angle, still 29.5 degrees, and tried cutting on the delrin and perfect threads.
Since I butchered the original part I have to make a new blank and start over.
Ed