Bridgeport spindle issues

[kaderick]

I am having issues with a bridgeport boss series I with a centroid retrofit. Surface finish is ****e. Had is trammed within .0005 or less.

T.I.R. is .0015 to .002 inside the taper of the spindle. If i put a guage pin in an endmill holder it's about .005.

Can anything be checked or adjusted. Or do I need to look at new bearings/grind job?

Any advice would be appreciated. THanks

[NC Cams]

Check P/M sent earilier today.

Also, do a search on this website for "bridgeport spindle" or the like. Quite some time ago, I gave a detailed explanation on what is involved in changing spindle bearings in Bridgeport mills. Perhaps someone has bookmarked the post link as I don't have it anymore.

The spindle bearings are NOT simple remove and replace items due to BPT's selective sizing and fitting of spindle bearings on their earilier spindles.

From your comments, public and private, you'd better plan on at least inspecting the bearings and, more likely, doing an ID grind of the spindle taper in an as-assembled condition.

Agani, completing the above search successfully should explain more fully why....