speed control retaining clip

[sp99keeler64]

It's hard to turn going from slow to fast, harder to turn going from fast to slow. Maybe that's the way it's supposed to be. I don't force it. Usually going from fast to slow I take hold of the speed control knob instead of the post that sticks out, and that works a little better.

[wa2crk]

what is the condition of the speed control quadrant? If the teeth are bent and not meshing properly it will also cause the speed control to be stiff.
Bill V

[DLB]

Assuming the parts you've replaced are all good, what I would do is disassemble the motor shaft and thoroughly clean the shaft, key, and inside of the floating pulley. It sounds like you lubricated this and it helped but sometimes that gunk that builds up in there has to be removed. (Same on the idler, but you said you've replaced the control sheave and I'm presuming that is all working OK.) When clean both the floating sheave and control sheave should slide effortlessly on their shaft (until you put the spring back on). After cleaning lubricate as normal. The other parts likely to be hard to turn are the notorious pork chop (aka quadrant) as Bill mentioned and worm gear shaft, but it sounds like you replaced those.

Harder to turn Fast to Slow is normal, you are compressing that spring on the motor shaft. I regard it as a warning if I can't easily turn the control both directions with the knob, because whatever the issue, it is putting more pressure on the parts that wear and fail due to strain: the quadrant and its bracket.

- David

[JPG]

Going back to the original 'issue', was there a roll pin(loose fit) in the control sheave bearing button that the ends of the clip fit into?

Now back to the present. To isolate the cause of the stiffness, I would first take the motor belt out of the picture. With the belt not interfering, the adjustment should be quite easy. if not next take the speed control out and determine if it works easily. You should be able to turn the shaft with bare fingers.

The control sheave should move(slide) VERY easily on the idler shaft.

If all that seems normal, the next thing to examine is the floating sheave on the motor shaft. Ignoring the spring force(easier said than done), the floating sheave should also slide very easily on the motor shaft.

I do not think a worn belt will affect this.

Sorry being late to this discussion, but I bin away.

[epodietz]

Over the period of 30 minutes or so my speed control on my SS 510 was becoming increasingly inoperational. The numbered scale was loose although I was still able to adjust the speed. I decided to remove the speed control (which seemed to have been well secured) and I found that the speed control retaining clip was broken, and there was wear on the quadrant assembly. Once removed, the speed control did seem to be working properly although I am guessing the worm gear might be a little warped owing to some partial sluggishness when the screw just starts to engage the first 2-3 threads of the worm gear. The entire assembly seemed to be passable according to Jacob Anderson's video on speed controls.

I do have a spare retaining clip for the speed control, however I first need to identify the underlying problem. Any ideas? Is there a seized bearing somewhere? With the speed control removed the SS runs fine. I am a little puzzled b/c I am not sure how the clip is supposed to attach to the control sheeve shaft because that shaft turns. I am hoping to avoid an entire headstock teardown. I did replace the motor bearings a few months ago, but did not get into the upper parts of the headstock.

A couple of things to note:
- Before removing the speed control I was able to verify that the sheeves are moving in and properly. They have been lubricated fairly regularly.
- What may have contributed to the problem was that I was turning a fairly heavy, irregular, green piece of ash and there was A LOT of vibration until I got it rounded.

Thanks much for any insight you may have!
Eric in Philly

[DLB]

...
I do have a spare retaining clip for the speed control, however I first need to identify the underlying problem. Any ideas? Is there a seized bearing somewhere? With the speed control removed the SS runs fine. I am a little puzzled b/c I am not sure how the clip is supposed to attach to the control sheeve shaft because that shaft turns. I am hoping to avoid an entire headstock teardown. I did replace the motor bearings a few months ago, but did not get into the upper parts of the headstock...

This pic was posted by Marc in another recent thread and makes for a good explanation:

Button Bearing Assy.jpeg (32.36 KiB) Viewed 1174 times

What you have in the pic is the clip assembly, button, and button bearing. This bearing is located in the control sheave and decouples the shaft rotation so the button and clip do not rotate. If the bearing seizes it will quickly destroy the clip. The clip can also be damaged if the control sheave is resistant to moving toward a faster speed, it should not have to 'pull' the sheave hard, if at all.

Quadrant damage usually corresponds to a speed control that is hard to turn. It is very important that the quadrant run true to the worm gear. In my experience there is usually other damage, either enlarged holes in the 'legs' that the quadrant pin hinges on and/or bent legs themselves. See the Bill Mayo improvement plan as a guide: download/file.php?id=34357 If there is damage in this area the quadrant or the entire speed control may have to be replaced, but the improvement is a re-enforcement I would recommend even with new parts. Your best bet is to submit some pics so the members can give you recommendations.

- David

[epodietz]

David: Thanks, that picture of the button bearing tells the story: The top part of my button bearing (where the clip is secured) is no longer there. Now to figure out the cause and how to remedy. I will post some photos in a bit.
Eric

[epodietz]

Here are some pictures of the speed control and damaged control sheave with what is left of the button bearing. It does seem to be seized.

It turns out that I have a new button bearing in addition to a new clip. Any recommendations on best instructional video for doing this job? Time estimate for a newbie?

I really appreciate all the expertise out there and hope some day I'll be able to help someone myself.

Eric

[br549]

I don't know of any instructional videos, but here are two links that may help; one that shares my experience, and one that I wish had been posted before I did mine as I liked redleg's approach much better. Mine is still working and my repair has lasted.

viewtopic.php?f=10&t=19133

viewtopic.php?f=10&t=19238

[DLB]

Here are some pictures of the speed control and damaged control sheave with what is left of the button bearing. It does seem to be seized.

It turns out that I have a new button bearing in addition to a new clip. Any recommendations on best instructional video for doing this job? Time estimate for a newbie?

I really appreciate all the expertise out there and hope some day I'll be able to help someone myself.

Eric

The Jacob Andersen videos are still up though Jacob has now fully retired and his parts store is gone: https://jacobvb.wordpress.com/youtube-videos-2/ I like his videos, they are direct and to the point. Try 'Control Sheave Inspection' first. There are separate videos on this repair, headstock teardown etc.

Your speed control appears to me to be repairable, but may require a new quadrant. The legs are slightly splayed, not severe though. The metal face of the quadrant that the button bearing rides on appears, in the pic, to be damaged so repair or quadrant replacement depending on how serious the damage. That is from metal-to-metal grinding action from the button after the bearing seized. That surface needs to be smooth from the rivet to the end, the button slides on it as speed changes. IIWM I'd do the Bill Mayo upgrade with either a new or reworked quadrant. A small file will typically return the quadrant rack gear teeth to acceptable condition if you can smooth out that metal surface.

- David