Shopsmith Forums

I’m having a problem with a Greenie I rebuilt and I’m asking for your help in resolving it.

This Greenie had an “A” casting and I rebuilt it from the ground up with new bearings and belts.
I had spare sheaves from previous rebuilds in addition to what was in the Greenie and I don’t remember what combination of sheaves and control quadrants I used in the rebuild. I Installed everything in a “B” casting. I did a high speed adjustment completing the rebuild. It didn’t smoke or grind after the rebuild so I used it as a sanding station trusting all speeds were correct since a high speed adjustment sets all the lower speeds.
I used it that way until recently when I realized there was an issue.
So I started to checkout and correct it.

The original issue was the original “A” style speed indicator dial. With JPG’s help I got a “B” style dial.
I installed it I and went through the high speed adjustment process again using a tach to set the high speed.
But things were just not right. I’ll go through what I did and and what the results were.

The control sheave moves freely on its shaft. Things are clean and oiled. The bearing turns freely.
I filed the teeth on the quadrant to ensure the worm shaft turns smoothly.
I positioned the drive belt about 1/8” from the outer rim of the drive pulley.
I turned the worm shaft to set the quadrant resting against the set screw high speed stop.
I manually opened the drive sheaves so the belt was free to move.
I installed the speed control with the indent at 12:00 and new new speed indicator with “Fast” also at 12:00. (I’ve read the How to Reset The Outside Speed Dial instructions and don’t understand any of it.)(BTW someone is trying to sell a copy of that on eBay for $19.95)
Closed the drive sheaves so the belt would run properly.
I used the sanding disk to manually run the speed down to about “M”.
While doing this I turned the disk a lot relative to turning the speed control a little.
The speed control was hard to turn with my fingers wrapped around the outside of the dial thing.
I plugged in and turned on machine.
It didn’t smoke or grind so I turned the speed control slowly to a slower speed.
It was still hard to turn.
I hit a somewhat hard stop at “G”. More of a bind rather than hitting a stop.
Magnetic tach meter shows about 1560 RPM (Specs say “G” should be 1450 RPM).

My questions -
1. Why would the speed control be hard to turn?
2. Why would there be a hard stop at “G” and not at “Slow”?
3. Why would the speed at “G” be so high?
4. Is it possible there are sizing differences between the “A” and “B” castings such that A stuff can’t be mingled with B stuff?

Thanks in advance for your advice.

oddie wrote: . . .
My questions -
1. Why would the speed control be hard to turn?
2. Why would there be a hard stop at “G” and not at “Slow”?
3. Why would the speed at “G” be so high?
4. Is it possible there are sizing differences between the “A” and “B” castings such that A stuff can’t be mingled with B stuff?

Thanks in advance for your advice.

1 - Bind between the worm gear and the quadrant gear / Slow response of the floating sheave on the motor shaft.

2 - Bind between the worm gear and the quadrant gear.

3 - +- 100 rpm not excessive.

4 - None that I am aware of.

Your sequence and procedure puzzles me.

The high speed adjustment does not require pre setting the belt position on the motor pulley except as a rough initial setting.

Setting the high speed stop is performed with the speed control installed into the headstock.

"Fingers wrapped around the outside of the dial thing" makes no sense. The knob should be turned, not the speed indicator ring.

The speed indicator ring is NOT directly connected to the speed controlling parts. It is merely rotated by an idler gear that is rotated when the knob is turned.

You DO have a KNOB?

Perhaps some pix will reveal something that is amiss.

As for filing the quadrant gear teeth, when done you should be able to easily turn the 1/4" shaft with finger pressure(out of the headstock). The worm gear does need to be centered on the quadrant gear.

In reading your questions about how your speed control is not working correctly, I agree with JPG's answers. My concern with what you are describing and have done was filing the teeth on the quadrant. If the teeth were bad because they have even slight bends or other problems this could be the cause of the problem you are still having. Bent teeth indicate too much force was used a some point to turn the speed dial. This may also cause the "arms" on the Control Bracket where the quadrant attaches to bend. Misalignment of these parts will make the speed control hard to turn. If the Worm Gear is not in a straight alignment with the Quadrant there is a problem. Lack of proper maintenance is the number one cause of this. Because the "A" Headstock did not have the access hole to lubricate the upper sheaves and other parts this maintenance did not occur as often as needed in some cases.

Please recall I rebuilt this machine and all the shafts are smooth and the bearings turn freely. This pic (see the last one below) is from a Shopsmith document, Appendix E, Maintenance and Troubleshooting and is my reference.


When I said I wrapped my fingers they were wrapped around the Speed Control Handle not the Speed Control Dial. It took so much force to turn I was afraid to use the little knob for fear I’d break it.

See below for some pics.

About filing the quadrant- initially when I removed the unit and hand-turned the worm shaft there was some slight binding at the point where the mechanism would be positioned for the lower speeds. With the filing the mechanism now hand-turns smoothly. So while the teeth are now filed the SS binds up just like it did before they were filed.

I’ve gone through this repair seven or eight times with the same result. I’ve used a tach and I’ve used the manual process to adjust the speed control. The last time which I described was done manually. I set the drive belt at the 1/8” point and the quadrant at the high speed stop as part of this manual process. Since I had had the speed control out to clean it, I set the quadrant against the stop per the same Shopsmith document (para 28f).

Unless I loosen the belt by spreading the motor sheaves allowing the idle sheaves to close the speed control will not lie flat against the casting so I can fasten it.

Is there any more info I can give you that may help this process? Thank you for responding.

When going from slow speed to fast the spring on the motor shaft is de-compressing and works with the speed control assembly as the upper sheaves separate. When going from fast to slow the motor spring is compressing so the speed control assembly works against that force to push the upper sheaves together. I believe the wear on your quadrant is still causing the problem. I have no doubt you have everything else moving freely. If you have another speed control assembly that is working try it in this Mark 5 and see how it preforms. If it is from another working Mark 5 try the problem speed control assembly in the other Mark 5 to see if it works or not.

I notice you have installed the tension pin fix/bent legs. The worm gear appears to be centered on the quadrant gear.

Since you indicated that filing the teeth made the control easy to adjust(out of the headstock), I have to assume the hard to turn is being caused by something else. Do realize a very miniscule interference between the worm gear and the quadrant gear teeth will create this problem.

I would remove the belt and check for binds etc. with the control installed with only the motor belt missing.

I would also make sure the floating sheave is free to move(pull it out by hand, but do not let it slip and bang the sheaves together).

OVER

Two things I failed to mention.
1. When I started this fix a couple of weeks ago I did a high speed adjustment. In that process I found that when I adjusted the 1” set screw up against the quadrant to set the high speed limit there were not enough threads left to fasten the lock nut. I then cut 1 1/4” piece out of a 1/4-20 bolt and cut a slot on the end for a flat blade screwdriver. With that installed there is about 1/8” of the bolt exposed.

2. I did lube the worm shaft with a small amount of white lithium grease.

Now I did as JPG suggested and disconnected the drive belt and manually turned the speed control. The speed control is still a little tough to turn but not as bad. The speed dial turned down to “B” and bound up. This position could be the real lower limit with the dial simply mispositioned. When I put the belt back and repeated the process under power the speed dial bound up at “F”.

The belt I’m using is a Shopsmith 504193. The width varies from .461” to .481”.

Just for fun the following pics show the physical alignment of the speed control handle at “V” and “F”.

I can pull the motor sheaves apart with my hands and the spring appears to compress and expand without any problems.

Are there any other things I can do or supply?

My questions are why is it so hard to turn the speed control and why can’t I adjust the speed down to “Slow”? Thanks again.

I still believe the quadrant is part of the problem. The worn marks on the teeth go from center to one side and if now re-aligned so the worm gear travels down the center could be causing the bind. In the new pictures I am wondering why the Control Handle is not mounting even. Is something else bent?

We need to determine why the knob is crooked. Is the worm gear shaft bent? Is the speed control base mounting to the headstock correctly(not skewed).

I think a pix face on with the knob removed may provide clues. Also pix of the quadrant gear and the control sheave match up.

Before I talk about the pics I must tell you about the latest development. I’ve had the speed control off and on so many times I’ve stripped the screw hole at the 3:00 position. I’ve repaired it and put in new screws. I don’t know if this issue played any part in my original problem.

The first pic shows the parts in the high speed position. The second pic is from the slow speed position.(see below)

The third pic shows the spring in the slow speed position. The next two pics show the belt position on the idler sheaves at the high and low speed positions. Please remember the “slow speed position” is at about “F”. (see below)

The sixth pic shows the worm shaft which appears straight. (see below). I rotated the shaft several times with the same result.

I’m sending a second post showing the quadrant.