Help with faceplate threads

[schemer]

Is there anyway the relief cut in back isn't large enough to fit the lathe boss or register it's called. If it's tight there it won't allow the threads to work . Try dykem on the inside before the threads . It may be there's not enough to allow the threads to enter. It looks like it's exact size to the pitch no room to move. Try spinning it on backwards .

Good thought. I didn't think of that as it doesn't screw on from either side and I assumed it was factory made for South Bend and should be perfect. But if someone else (or even the factory) didn't do that correct you would think there would be tool marks past the threaded area. On the back side anyway. But the adapter does contact the threads from either side but only turns at most 1/8 of a turn (like from 9 to 10 on a clock). I will give it a good look at though.

 

[schemer]

Just a followup. I ran the tape through the two adapters and my part only fit the first one so I guess the foirst one was cut sloppy. So I a tooled up and ready to make a new piece and do it right this time.