The usual noobie mistake -help please

[retiredsoldier919]

So I of course tried to turn my speed control without the pulleys moving. So of course something is wrong. My Mark V 510 slowly spins then the circuit trips. Here's what I know so far:
1. I've got it plugged directly into a 20amp circuit . No extension cord.
2. I've manually rotated the spindle to spin the speed control back to slow setting. Starting in slow is no different. It slowing spins and trips.
3. I've removed the belt to the motor to start it without a load. No problems with the motor starting without a load.
4. Manually rotating the spindle while turning the speed control I notice that it gets very hard to turn as I get closer to the slow setting. Is that normal?
5. I don't know if I have damaged the speed control. It looks okay to me.

Any advice is very appreciated.

[reubenjames]

You said you removed the drive belt to start the motor without load; did you replace the drive belt when you performed the test in Step 4, then, where you manually rotated the spindle while turning the speed control? You'd have to pull the speed control and check it over, especially the teeth, to see if there is damage, and to what extent. But a damaged speed control shouldn't pop a circuit. If the motor is actually ok, it's usually bearings that are starting to seize on one of the shafts, or the belt isn't sitting right or tensioned correctly. If you've neglected oiling, then your sheaves don't always float as easily as they are supposed to, and that can cause speed changing problems and extra load on the motor. However, it sounds like you weren't having any problems before you turned the speed control with the motor off, is that correct? Or is this a new ShopSmith that you haven't tested before?

[JPG]

Lets start at the 'control' end.

Remove the motor belt. That removes the need to rotate the pulleys as the control knob is turned.

Have you oiled the control sheave recently?

The control knob should easily control the entire range slow to fast to slow. If not, a closer look is required. The motor belt must be kept out of the way during that.

A look inside may reveal why it is hard to turn.

Now if the control knob moves easily, we need to look at the motor shaft and pulley.

Have you oiled the floating sheave recently?

"Over"

BTW which direction did you turn the control knob? Towards fast, or towards slow?

Oh and I assume the control knob gets hard to turn towards slow, not the spindle.

[retiredsoldier919]

You said you removed the drive belt to start the motor without load; did you replace the drive belt when you performed the test in Step 4, then, where you manually rotated the spindle while turning the speed control? You'd have to pull the speed control and check it over, especially the teeth, to see if there is damage, and to what extent. But a damaged speed control shouldn't pop a circuit. If the motor is actually ok, it's usually bearings that are starting to seize on one of the shafts, or the belt isn't sitting right or tensioned correctly. If you've neglected oiling, then your sheaves don't always float as easily as they are supposed to, and that can cause speed changing problems and extra load on the motor. However, it sounds like you weren't having any problems before you turned the speed control with the motor off, is that correct? Or is this a new ShopSmith that you haven't tested before?

I did replace the belt after the no load test. I purchased this unit recently from a guy who said his father bought it in the late 80s and never completed setting it up. It appears to have never created sawdust in its life time. I did have the seller power it on before buying it. But at $200 I didn't do a thorough inspection. I would have bought it wven if it didn't power on. Too good a deal.

[retiredsoldier919]

Lets start at the 'control' end.

Remove the motor belt. That removes the need to rotate the pulleys as the control knob is turned.

Have you oiled the control sheave recently?

The control knob should easily control the entire range slow to fast to slow. If not, a closer look is required. The motor belt must be kept out of the way during that.

A look inside may reveal why it is hard to turn.

Now if the control knob moves easily, we need to look at the motor shaft and pulley.

Have you oiled the floating sheave recently?

"Over"

BTW which direction did you turn the control knob? Towards fast, or towards slow?

Oh and I assume the control knob gets hard to turn towards slow, not the spindle.

Yes. I did oil the two sheave holes, as instructed in Jacob's Youtube video. I will try your suggestions. I viewed Jacob's speed controller video on YouTube and will inspect it closer. Thanks for your quick reply.

[retiredsoldier919]

I followed JPGs advice and checked the speed control with the belt off the motor. The speed controller moved smoothly throughout the ranges. I also disassembled the speed controller and I see no damage. After reassembly, I reset the speed controller as described by Jacob's Youtube video. I did notice my saw ran longer when starting with the speed set to the middle range. It still trips the circuit. I think I need to:
1. Disassemble the motor and pulley. See if the motor is somehow dirty or defective.
2. Double check my circuit to see if there's a bad outlet, wire or breaker.

Speed controller

20160424_162621-600x800.jpg (97.43 KiB) Viewed 2121 times

[ChrisNeilan]

Does the breaker trip when the speed is set to the slowest setting? Start up on higher speeds can trip breakers, especially 15 amp circuits.

[JPG]

Take a close look at the floating sheave(motor shaft).

Remove the belt and manually pull the floating sheave away from the fan sheave. It should move somewhat easily(you are overcoming the spring tension).

DO NOT LET THE FLOATING SHEAVE SLIP AND BANG INTO THE FAN SHEAVE!!!

This will determine if oiling was effective. I am guessing it was not. It is difficult to get sufficient oil through the hole 'under the spring'.

With it in vertical position. dribble oil onto the keyway and let it sit overnite(to allow it to seep onto the shaft etc.).

[reubenjames]

I had the same issue with my '85--the fan sheave and floating sheave did not like to move, and this put undue stress on the motor when the belt was connected and you tried to move through the speeds. I had to pry the two sheaves apart with screwdrivers to even get them to separate--this is not normal! Of course, the cord in the ShopSmith had also ended up being damaged, so I would also carefully inspect the cord--the portions both inside AND outside the headstock. I believe the cord damage had also contributed to my issues at that time.

[JPG]

I had one that required 'live' blow hammering to separate. 'Less' than gentle persuasion!

Trick is to not break.