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Gadgets, Gizmos, and Dohickeys => Cutting, Grinding, Polishing => Topic started by: Talusman on August 15, 2016, 04:50:17 AM
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Last night my 10" slab saw jammed while cutting rough. When it happened the motor shaft stopped, but it sounded like something was still turning In the motor. After clearing the jam, the motor still runs, but instead of starting with authority like it used to, it takes 5 seconds or so to slowly get up to speed when starting. There's no obvious capacitor on the motor and there was no smoke/oil like from a failed cap. Ideas on what damage may have been done? Thanks!
-Jeremy
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Most likely a burned connection. Open the access plate and check all wire connections. You may have to do some internal disassembly. If all looks good and there is no capacitor, and it still doesn't start with no load then it's new motor time.
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Intrresting, waiting for the answer since I have one doing the same.
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Thanks for the help, but I'm not sure I understand. The motor starts and runs - it just takes several seconds to get up to speed. Prior to the jam it would start spinning fast immediately. Would a bad connection still allow the motor to run?
Thanks!
-Jeremy
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Hi Jeremy
It takes a lot more amperage to get the motor started than it does to run. That is why a lot of ac motors use a starter cap. If the motor does not have a starter cap then a bad connection could limit the current getting to the motor causing the slow start. This can also happen with a motor with a starter cap. A jam also can cause some of the wireing to get hot and melt just enough to cause this situation also.
I would agree check all connections and and if they dont look burnt then try to listen to it when you try to start it. If you hear some slipage you have a very bad problem. Also if there is no starter cap and all connections are good then the motor probally got hot enough to melt some of the insulation of the internal windings and the motor will need to be replaced.
Hope this helps
Bless
Shawn
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Thanks - I will check out the motor tonight. It was strange that it seemed to be moving internally like a clutch was slipping or something. Not the hum I'd expect from a stalled motor. No burnt smell either.
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Was it the shaft or the pulley that stopped? No smoke, no smell, check the pulley. If the set screw is loose, the motor will turn but the saw will come up to speed slowly as the shaft turns inside the sheave. This would be a blessing as it is very easy to fix and does not require a new motor.... Just another possibility.
Bill
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Ding ding ding... Bill's the winner. I actually figured this out myself (honest :idea1:). A turn of a screw and it's running again. The issue that caused the jam was that the vise base plate had shifted. Tightened that too. That's to all for the help!
-Jeremy