My spanner arrived from Enco along with my R-8 collets. I adjusted the alignment pin on my PM935TV, which was totally easy with the spanner. I then took a new 1/2" collet (import) and mounted a .500 gage pin (also imported). When I put a .0005" dial indicator on the pin, it was within .001" concentricity, just barely. Is that good runout for this kind of setup? It's the only collet and gage pin combination I've measured so far. When I measured my quick change MT3 collet and Glacern keyless chuck with a 1/2" drill, it was more like .003 to .004, which didn't excite me that much.
My only other milling machine was a Grizzly 6x26, but I never tried to measure runout on it, so I don't have much of a basis for comparison. I do know that the outside of the spindle on the 935 spins with no measurable runout on this dial indicator. I'd need one calibrated for tenths in order to measure that at this point. My mentor suggested the more useful test would be to measure the runout of the taper inside the spindle, but I've not had time to pursue that yet
My only other milling machine was a Grizzly 6x26, but I never tried to measure runout on it, so I don't have much of a basis for comparison. I do know that the outside of the spindle on the 935 spins with no measurable runout on this dial indicator. I'd need one calibrated for tenths in order to measure that at this point. My mentor suggested the more useful test would be to measure the runout of the taper inside the spindle, but I've not had time to pursue that yet