Spindle cleanup

[wsippola]

While trying to center the 3D taster I got, I found I was getting about .0035 runout on the endmill holder. I turned it 180 deg, and the runout stayed with the spindle orientation, not the the holder. Upon inspecting, I found it had an area that had been dented with swarf.

I tried a scraper, but it was far enough in and hard enough, that I figured I would do more damage than good. I decided to tilt the head and use the head from my tool grinder to clean it out. Can't take much, as the taper will go in deeper by several times the amount removed. Here's a photo setting the angle on the head with an indicator attatchment.

I centered the grinding wheel by moving the table for and aft until the wheel touched, then centering it. The table feed was used to move the grinder in and out of the spindle. It started out pretty good, but at some point I bumped the crossfeed on the mill putting the wheel off center. This caused the inner end of the taper to be ground more. I re-centered, and cleaned most of it up, but the inner end is still large. I could have continued to clean that up, but I didn't want the tool holders going in too deep. I used a marker to "blue" a new tool holder and marked the spindle taper - you can see the far end does not touch. Overall, it came out fine but there may be a slight loss of rigidity with only the last 2 inches of taper contacting - doubt I will ever notice.

[spro]

This is one of those where enormous set up (in our way) to do this, has already been done. Kinda dum for me to say about an operation which I never did. I do understand your concern about the back end of the taper We can look at it as the drawbar may keep it orientated and the keys for drive remain. It would nag me also, that lack of contact at the end of taper. Better brains than mine around here. It could come down to "it's gong to be just fine if you don't push it" but that's not what you want. I can't tell you to do what I haven't had to. I recall the taper stands out, the tooling it stands out a bit so the internal could be ground the full length. Yet that is too easy for me to say.
I believe HV would have something to say about this, if we want the truth.