Jet Benchtop Spindle Sander - chatter

[Scott Bernstein]

I have the jet benchtop spindle sander. Fairly happy with it; constructed better than the
Rigid unit. I am having some chatter on the spindle, especially towards the peak of the
upward stroke of the spindle. Any other adjustments that can be made other than making sure
the sandpaper is on as straight as possible? It is not terrible, but far from
perfect. I haven’t checked the runout on the bare spindle, but I do
plan to do this too.

SB

[Robert Hayward]

I had one of those, a JBOS-5 and it did the same thing. Annoyed me so much I sold it and bought a Grizzly G1071. Smooth as silk. Besides the spindle also check the runout of the rubber sleeve that goes over the spindle. Check it with out any pressure on the top spindle nut and again with pressure from the top spindle nut. Do this check without a sleeve on the rubber piece and again with a sleeve. This will let you know if your sleeve is causing the problem or the spindle/rubber.