I recently acquired ( thanks Iazz!) A B&S .0005" dti and have taken some preliminary measurements of the spindle of my approximately 140 yo Stark #4 lathe/mill. I measure .0005 - .0010 variance on the inside taper of the spindle. There are 2 noticeable and repeatable lobes, one high, one low about 180 degrees apart. This is perfectly fine for my use but I was wondering if the huge 3 jaw chuck that was attached to the spindle for many years could cause this?
I also measured the run out about 2" from the headstock with a 1/2" ground test rod held in a collet. Got a nicely repeatable +- .0005, so .0010 in total with the high & low spots in about the same place rotationally as in the spindle test.
I also measured the run out about 2" from the headstock with a 1/2" ground test rod held in a collet. Got a nicely repeatable +- .0005, so .0010 in total with the high & low spots in about the same place rotationally as in the spindle test.
