Jet 1642 - Strange Noise

[Edward Weingarden]

I've got a Jet 1642 that's about 10 years old. It has always run without any issues. Today I mounted between centers a log 12" diameter x 12" long to turn an end grain hollow form. The log was well balanced so I took the lathe up to about 800 rpm slowly and there was minimal vibration. When I shut the lathe off there was a scraping sound as the log was slowing down. It only lasted a few seconds; the noise stopped before the lathe came to a stop. I took the speed up slowly again but brought the lathe to a stop by turning down the variable speed control. As I slowed the lathe, the noise occurred again, only for a few seconds. Next, I repeated the slow start but turned the speed down very slowly to a stop; there was no scraping sound. I went ahead and turned the log into a cylinder and the scraping sound no longer occurred when stopping the lathe. Anyone have any thoughts as to what was making the sound? Should I be concerned? Thanks.

[Len Mullin]

Edward, from what you describe, I think that you may have a bearing going bad. On one of my older lathes I had the same issue with noise, as soon as I changed the bearings the noise was gone and never returned. It was like a grinding or scraping type of noise, and it only occurred at certain speeds.
Len

[Phil Rose]

It has been quite a while since I had a noise in my Jet, but it turned out to be a loose hand wheel. Once I tightened the hex nuts a bit more it went away. I can't recall exactly the noise, but I'd check for loose screws first.

[Thom Sturgill]

I agree with Phil. On the other hand the Jet uses shielded not sealed bearings. they are relatively easy to replace and there is an old thread on here about how to replace them: http://www.sawmillcreek.org/showthread.php?155720-How-I-Changed-Jet-1642-Bearing

[Russell Neyman]

I've worked on several of these. Open it up and tighten all the set screws on the various pulleys and fittings, for sure, but this really sounds like a bearing. Changing them out (not a bad idea after ten years anyway) isn't too hard and they can be had at most machinists supplies. PM me and I'll send you a
link on an tutorial.

[Edward Weingarden]

I tightened all of the set screws, although none felt to be loose. I'll reassess once I mount another large log. Thanks for the feedback.