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Steve Kirincich
11-30-2020, 1:13 PM
Hello,

I recently purchased a used Jet JTAS10 table saw, and have noticed that the arbor binds up when raised to it higher height range. This happens whether or not the blade is installed. I can smell the hot rubber from the belts and do see a few sparks when making a cut, but when forcefully turning the blade by hand, I see no metal-to-metal points of contact. The shaft which gets turned for adjusting the blade height has some score marks and the arbor assembly becomes hot. Views from the top and bottom are limited and I am ready to remove the top to get a better view. Any suggestions before I take a deeper dive? The photos from above may not be helpful.

Thanks,
Steve

Bruce King
11-30-2020, 2:47 PM
My 1992 cast iron TS does not have an upper stop.
compare the rated cut height with what you can do without rubbing to see if there is a defect.

Jon Grider
11-30-2020, 2:58 PM
Is that belt rubbing on the height adjustment shaft? Looks like a possibility from your pics.

Bill Dufour
11-30-2020, 3:28 PM
don't raise it too high, problem solved.
Bill D.

Matt Day
11-30-2020, 3:38 PM
If this is at max height, the pulley may be running on the bottom of the table. Metal on metal = sparks.

That same pulley or the motor pulley or both is likely out of adjustment pushing the belts into the shaft of the blade raising wheel.

Steve Kirincich
11-30-2020, 3:50 PM
Thanks for sharing your thoughts. The arbor does not bind at the 3" maximum cut but does bind when raised at about 2". Somewhere below 2", the arbor once again rotates easily.

Richard Coers
11-30-2020, 4:14 PM
Sparks inside a table saw means a shop fire. Pull the top before that happens!

Lee Schierer
11-30-2020, 4:26 PM
Did someone put the wrong belts on the saw, pulling the motor up too high? That discoloration on the shaft is definitely not normal. Take a look at the pulley on the motor.

Bruce King
11-30-2020, 5:15 PM
Also check the adjustment shaft, might be bent where it rubs on same spot every one turn.

Steve Kirincich
12-01-2020, 2:10 PM
Update:

I removed the top of the saw today and noticed that there was an alignment issue between the arbor and motor pulleys. I thought I could loosen the set screws on the motor fully and give it a few taps but it did not move. Then the moment of clarity. I loosened the motor mounting bolts, gave the motor a good pull and checked the alignment. That seemed to improved things and moved the belts and pulley away from the adjustment shaft. This took way too long but I now know this machine much better! The photo below unfortunately was rotated when it was inserted in to this message, but the alignment issue can be seen.

Thanks again.

446086

Bruce King
12-01-2020, 11:52 PM
Good work, looks like Jon nailed it on one of the early posts.

Steve Kirincich
12-02-2020, 12:13 AM
Thanks Bruce. It was an easy fix done through an unnecessarily complicated route. While on this deep dive I learned a lot about the machine. Having found a few parts that are starting to show signs of wear, I have debated getting replacements for them before they become unavailable in the next few years.