Tightening pot shafts? Any tips?

[olddawg]

I have a resonator electric that has some weird ass controls. The guitar has a mini humbucker and a piezo pickup with a volume control, a blend pot, and a tone control... NO PICKUP SELECTOR SWITCH! It's very versatile when you have time to mess with it. But.. using it live with a timely guitar change on stage can be a real pain. What happens is the pots are too easily turned. I don't want to tear it apart and rewire it. Does anyone have any tips for stiffening up the pot shafts? I know StewMac makes these felt pads that fit under the knobs to affect some resistance to turning control pots. What do most people do?

[Chuck H]

Sometimes Alpha pot shafts will stiffen if I over tighten them. I can't say that this would be a good practice in general and try it at your own risk. I have attempted to tighten shafts by evenly pinching around with pliers. DON'T try that. I've had pots loosen after cleaning. The heavier grease gets washed out of the shaft. So if there was a way to get a heavier grease into the shaft bearing that might help. I'm thinking you could start with something like melted bees wax (because it's more sticky than others) and use a cheap syringe to inject it. If you can get it into the shaft bearing it might be quite stiff and resistant once it cooled.

[Enzo]

Try slipping a small rubber O-ring over the shaft before the knob. Now the knob has the rubber acting as a brake.

[olddawg]

Try slipping a small rubber O-ring over the shaft before the knob. Now the knob has the rubber acting as a brake.

That's a great idea! The O-ring will rest against the nut and washer. The StewMac things are felt.

[Mick Bailey]

Here's what I do;

Spray some PJ1 Blue motorcycle chain lube into the lid and let it thicken as the solvent evaporates. Then cut off at an angle the end of a cotton bud (Q tip) - the ones that have a hollow plastic straw. Dip it into the thickened lube and apply it to the shaft/ferrule junction. It needs just enough residual solvent to get in there, but not enough that it creeps everywhere. Leave it overnight.

I've done 100s of pots this way to restore the silky resistance to as-new feel. If I'm rebuilding a pot I let the lube thicken right up and apply it during assembly. This stuff is really viscous and stays put.

There are limits, though. If the pot is badly worn no grease will cure it.

[eschertron]

PJ1 Blue motorcycle chain lube

Cool! I may have to stop by the motorcycle store on my way home tonight, PJ1 indicates them as a dealer. Sounds like a good thing to add to the bag of tricks

[g1]

Maxima chain wax would probably give similar results, if your dealer doesn't have PJ1 Blue.
Mick, have you compared them?

[epis]

Tamiya 53176 RC Model Friction Damper Grease (Hard) | eBay

[Chuck H]

The idea of a stiffer grease seems fine. That was the direction I was going with the beeswax. I figured the beeswax would sort of marry with whatever is already in there and make a thicker goo. But not all pots can be disassembled in a way that allows access to the shaft bearing. I suppose products that start thin and evaporate solvent to thicken would be better if you have to just try and "get some in there". If the shaft can be removed you can pretty much use any sticky, heavy grease you like. It's not like a pot ever gets turned at any significant RPM's.

[g1]

Seems to me there was some specific Tapco grease for their mixer pots. Enzo may have a stash somewhere.

[Enzo]

Actually it was the other way around. Tapco pots over time got so stiff you literally couldn't turn them. I USED to have a can of solvent for whatever was on the shafts to loosen them up. It was not a commercial product, it was some chemical name like phenolallapastacarbonara.

[g1]

Ah, ok. Now you mention it I do recall them getting overly stiff. It was probably a particular Tapco branded solvent we had.

[Chuck H]

Actually it was the other way around. Tapco pots over time got so stiff you literally couldn't turn them. I USED to have a can of solvent for whatever was on the shafts to loosen them up. It was not a commercial product, it was some chemical name like phenolallapastacarbonara.

That reminds me of something a customer said to me while I was priming his trim... "Well, I'm gettin' outta here. It smells like whatever you're puttin' on is full of Dimethylsomthinawful."

[Mick Bailey]

Maxima chain wax would probably give similar results, if your dealer doesn't have PJ1 Blue.
Mick, have you compared them?

I've been using PJ1 for as long as I can remember (so that's at least three days.....). I've never compared it to Maxima, so I can only go on what I know. I did get a pot of the correct damping grease for pots, but I went back to PJ1 as it works better.

I guess most chain lubes will have similar properties (other than those maybe with PTFE, moly, or graphite). They go on thin, thicken up and have to resist flinging off, water and salt spray. PJ1 is also available in small cans.