Wide-Belt Sander Shutting Down

Troubleshooting a wide-belt sander that cuts out intermittently for no apparent reason. May 23, 2007

I have a 43" Timesavers sander and over the past month it has been shutting down both when Iím running material through it and when Iím not running material through it. This is a more recent issue that Iíve been having and it never used to happen at all. Sometimes the machine will run for 10 minutes with no issue and then it wonít last 10 seconds without stopping.

I checked to see if the belt was hitting the triggers (not sure of the exact name) on either side that automatically shut the machine down but thatís not the issue. Plus Iíve widened those both another 1/4" outwards to make sure the belt wasnít hitting the triggers. Iím wondering if its an electrical current issue or does it have to do with the machine itself since it just started doing this recently. Has anyone had an issue like this and if so how did you resolve it?

Forum Responses
(Solid Wood Machining Forum)
From contributor C:
I would suggest that you check to see if it is a matter of insufficient air pressure/delivery rate.

From contributor J:
We had that problem at a job I had. The infrared eye was getting too dusty, so they put a low pressure air line to keep it clean. The guys wood just hit a button every few minutes of operation and it worked great! It stopped screwing up work and destroying belts.

From contributor A:
Contributor J - that is a great tip.

From contributor B:
If you are comfortable doing so, open the electrical panel and check the tightness of all electrical components. It is fairly common for connections to loosen over time. If you have a connection that is loose in the contactor (start/stop) circuitry your problem is exactly what will occur.

Start first with the stop button connections. The stop button opens the contactor circuit subsequently stopping the machine. A loose connection in this circuit will have the same result. Also, if the machine has an emergency stop bar (like mine) look to make sure that isn't rattling into the stop button behind it.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor P:
There are several reasons for the machine randomly shutting down. When it shuts down, does the whole machine shut down or just the head? Some timesavers sanders used safety perimeter bars surrounding the machine. This is basically like a horn switch on a car with two copper strips separated by about a sixteenth inch air gap. Temporarily bypassing that circuit would isolate the problem to that. As for dust on the tracking eyes, excessive dust would cause the belt to mistrack and you mentioned that wasn't happening (belt hitting the mistrack switches). There is also a fork that straddles the mistrack switch on the motor side of the machine. Make sure it is not touching the mistrack switch with the belt loaded.

Another possibility; is the incoming voltage within 10% of the voltage the machine is rated for? Less than that and the control circuit could drop out due to not enough control voltage to maintain the control circuit relay.