Shopsmith Forums

Could it be a cold solder joint on the motor? Did they "try" to repair a broken winding? Is the starting cap correct?

If its a split phase, is the centrifugal switch ok?

It all points to a motor problem.

I have found several headstocks with the sounds of a motor surging. These were all due to the motor floating sheave sticking as it tries to close when going from SLOW to FAST and stopping at any point for a while like when first starting the headstock. It was very noticeable when watching the motor belt jumping in the sheaves.

I have not found that any motor, switch or voltage problem(s) has caused a surging of the motor. Normally, either the motor hums or does nothing when turned on if there is a problem.

If it were me, I'd do what Dusty recommended in order to confirm what Bill said. Run the motor with the drive belt removed and see if it still surges.

If you turn the motor on and just let it run, does it continue to surge or does it eventual level out? Does it only go through the surge for a few seconds after being turned on or does it continue after it's been running and otherwise untouched after turning on?

You say the motor bogs down when you use the saw... what speed setting are you using?

heathicus wrote:You say the motor bogs down when you use the saw... what speed setting are you using?

I'll add is the saw blade SHARP and clean or the wood wet?

I have to agree with Bill Mayo, I can't think of problem in the motor what would cause a surge. My guess is it is either the pulley like Bill mentioned or power. I would probably bet on power until you said it worked fine then it began to rain and now you are having a problem. My guess now is pulley sleave bound up.

That all said have you monitored the power coming into your home. Perhaps there is a voltage drop when it rains. I would be tempted to measure the voltage and see how constant it is.

You start adding a voltage drop, a machines that needs lubed, perhaps a dull blade, humidity to effect the wood and coolness and it adds up to unsatifactory performance when cutting.

I have to agree with Bill Mayo, I can't think of problem in the motor what would cause a surge. My guess is it is either the pulley like Bill mentioned or power. I would probably bet on power until you said it worked fine then it began to rain and now you are having a problem. My guess now is pulley sleave bound up.

That all said have you monitored the power coming into your home. Perhaps there is a voltage drop when it rains. I would be tempted to measure the voltage and see how constant it is.

You start adding a voltage drop, a machines that needs lubed, perhaps a dull blade, humidity to effect the wood and coolness and it adds up to unsatifactory performance when cutting.

OK Ed....we got your point.....both times:D .

As usual Bill Mayo has the most likely answer! How freely does the floating sheave on the motor shaft move to and from the fan sheave. Although the spring is stout, you should be able to move it in and out by hand(with the belt off). Do NOT let it slip and bang into the fan sheave. Methinks in is crudded up and the higher humidity makes it 'stickier'. If the floating sheave is not free to move you will not have adequate tension and the motor belt will slip under load.

This is consistent with all your 'symptoms'!:)

Yeah, I agree with Bill too. Like I said early in this thread - clean it and lubricate it and adjust the belts for proper tension - after you check to confirm that the motor runs normally with the drive belt removed.

mickyd wrote:OK Ed....we got your point.....both times:D .

I don't know how that happened and I didn't know it happened to I came back to read Dusty's comment. I have deleted my duplicate.