After installing a collet closer attachment to my Grizzly G4002 lathe, I checked the stock with an indicator, as theoretically speaking, stock held in a collet should run relatively true. The stock was found to be running out by 0.002. So I took the nose cone out of the taper and ran an indicator on that and found that the spindle itself was running out 0.002. Is there a fix for this? Or is it, as I suspect, insignificant enough as to not warrant any action at all.
0.002 Runout on Spindle, Fix?
- Thread starter MattMaie
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2 thou is a lot for the lathe spindle register.How important it is depends on what you are making.My chinese chucks have a nom runout of 2-3 thou
and for most things I am happy with it.
What lathe ,how old etc.If you know its there you can compensate when its required
and for most things I am happy with it.
What lathe ,how old etc.If you know its there you can compensate when its required
It's a G4002 lathe from Grizzly, and its about ten years old so it is no longer covered by warranty. I know that Grizzly isn't the greatest lathe out there, but at the moment I can't afford anything better, so I will have to make it work.
Grab a one-foot length of bar in the chuck. PUt the dial indicator on the spindle behind the chuck. Grab the end of the bar and yank it up and down. If the dial indicator moves more than a few tenths of a thou, your bearings need adjusting or possibly replacing.
Most of the Chinese lathes that size run taper roller bearings that need adjusting for slight preload occasionally. They are often mediocre quality bearings so if you have to replace them, get good USA made Timken bearings and they will last a lifetime.
Most of the Chinese lathes that size run taper roller bearings that need adjusting for slight preload occasionally. They are often mediocre quality bearings so if you have to replace them, get good USA made Timken bearings and they will last a lifetime.
If you find it is in the spindle and not in the bearings, then your only recourse is to borrow a toolpost grinder and regrind the nose taper true.
I have had to do this every time I fitted a new 5C collet chuck (4 up until now), the cheaper ones never run exactly true, and I have also reground commercially made ER collet chucks for friends as they are no better.
If you can get a friend to loan you his grinder and also get him to do the job for you (he should already have gone through the learning curve), once the correct angle is found, it only usually takes a few minutes to get things ground perfectly.
John
I have had to do this every time I fitted a new 5C collet chuck (4 up until now), the cheaper ones never run exactly true, and I have also reground commercially made ER collet chucks for friends as they are no better.
If you can get a friend to loan you his grinder and also get him to do the job for you (he should already have gone through the learning curve), once the correct angle is found, it only usually takes a few minutes to get things ground perfectly.
John
