Cleaning and re-lubing potentiometers

[Alex SE]

Have two potentiometers from some Technics donor deck. Very, very little used, as new but still 30+ years old. They are kind a hard.
Anyway, I couldn't resist and opened one to see what can and need to be done with it. Electric side was as new. The part that need a little love is a shaft itself. Grease is hardened pretty much so I've cleaned it nicely and then the question came up: what grease to use on a plastic shaft.
Have a lithium, silicone, some mineral grease and Molykote EM-30L.
My thoughts:
Lithium and Molykote are too light, almost as Nivea hand cream.
Mineral, I think I have seen somewhere, somebody said that mineral grease have a bad impact on plastics.
Silicone, seems as a best choice of all I have. Lubed a shaft with it and it turns now much more smooth and easy.

Everybody talks about cleaning electronic part with a contact spray, but I've never seen anything about lubing a shaft. I'm wondering what's your opinions, what would you recommend.

 

[WOPL Sniffer]

Deoxit Fader GREASE

 

[J!m]

Yep. Deoxit grease.

And the track should be cleaned with Fader lube (F5) or F100. D5/D100 will destroy a carbon comp pot fast.

 

[WOPL Sniffer]

On the shaft, 1 small drop of

https://www.ebay.com/itm/2305269962...yFKYmOpHVvGlw7L57tu74TdrPB|tkp:Bk9SR4K0n8XJYQ

 

[J!m]

Dielectric (silicone) grease if nothing else is available.

 

[George S.]

DeoxIT Fader Grease, DFG-213

 

[62vauxhall]

A lifelong service tech, now deceased, told me to use Tri-Flow on rotary controls. I had an extremely stiff input selector on a Heathkit tube amp. The stuff worked like a hot damn.

 

[Alex SE]

Now that Deoxit Fader grease looks very interesting. I use to use contact spray on a graphite tracks, some PRF 7-78 which is of course unknown for you guys in the US, but that Deoxit grease looks nice. Price in Sweden for that little plastic can is about 30$ and for Deoxit D5 142gr (5 OZ) about 30$ too.


Anyway, the question was about shaft, not graphite tracks. I mean around a shaft. Good to know that dielectric silicone is OK for that job.

 

[Alex SE]

A lifelong service tech, now deceased, told me to use Tri-Flow on rotary controls. I had an extremely stiff input selector on a Heathkit tube amp. The stuff worked like a hot damn.

View attachment 74040

Is it some kind of oil or grease?

 

[George S.]

Now that Deoxit Fader grease looks very interesting. I use to use contact spray on a graphite tracks, some PRF 7-78 which is of course unknown for you guys in the US, but that Deoxit grease looks nice. Price in Sweden for that little plastic can is about 30$ and for Deoxit D5 142gr (5 OZ) about 30$ too.
View attachment 74038

Anyway, the question was about shaft, not graphite tracks. I mean around a shaft. Good to know that dielectric silicone is OK for that job.

The DeoxIT grease looks suspiciously like a little tub of Danco plumbers grease I have. Pretty sure it's just plain old dielectric silicone grease like Jim said.
His point about "dialectic" is spot on. Regular greases and oils will cause shorts.

 

[62vauxhall]

Is it some kind of oil or grease?

It is petroleum based liquid. I found it at an auto parts store but I believe it's marketed more towards bicyclists.

An online description:

Tri-Flow Superior Lubricants light viscosity allows for deep penetration into hard-to-reach moving parts. Its a great all-purpose lube that excels in any and all conditions. Use it on your chain, cables, derailleurs and all pivot points.

Features

• The drip bottle application, with a convenient straw, allows for deep penetration in hard to reach moving parts.
• High-grade petroleum oils provide optimum lubrication under extreme temperatures (-60 to 475°F) and humidity.
• Formulated solvents soften and remove dirt and contaminants, while special additives displace moisture and prevent rust and corrosion.
• Formulated with P.T.F.E.

 

[WOPL Sniffer]

all your questions have been answered, your choice. I do A LOT of faders and they get a half drop of the liquid bearing (On the shaft)

 

[George S.]

It is petroleum based liquid. I found it at an auto parts store but I believe it's marketed more towards bicyclists.

An online description:

Tri-Flow Superior Lubricants light viscosity allows for deep penetration into hard-to-reach moving parts. Its a great all-purpose lube that excels in any and all conditions. Use it on your chain, cables, derailleurs and all pivot points.

Features

• The drip bottle application, with a convenient straw, allows for deep penetration in hard to reach moving parts.
• High-grade petroleum oils provide optimum lubrication under extreme temperatures (-60 to 475°F) and humidity.
• Formulated solvents soften and remove dirt and contaminants, while special additives displace moisture and prevent rust and corrosion.
• Formulated with P.T.F.E.

We used Tri-Flow on firearms in the USAF. The bottles came in cardboard boxes with National Stock Number stickers on them. Think it's also popular as a "wet" chain lube, although "dry" wax based lubes seem to be more popular for cyclists these days. I prefer wet lube on my chains and pivot points.

 

[J!m]

Smells like bananas. I use it on chain and cables of the bikes.

 

[Alex SE]

all your questions have been answered, your choice. I do A LOT of faders and they get a half drop of the liquid bearing (On the shaft)

...and I'm really thankful for all advices.

 

[Alex SE]

The DeoxIT grease looks suspiciously like a little tub of Danco plumbers grease I have. Pretty sure it's just plain old dielectric silicone grease like Jim said.
His point about "dialectic" is spot on. Regular greases and oils will cause shorts.

That's it, dielectric it is

 

[WOPL Sniffer]

you just have to be careful, if you lube TOO much, it can run through the shaft and contaminate your pot inside so it will have contact issues. The Liquid Bearing stuff has a nice needle tip and allows you to be very stingy with your lube as you can always add more but you can't take it back. The dielectric stuff is hard to get where you need it but do as you wish.

 

[WOPL Sniffer]

I'd skip that big ass bottle of KY lube.... You cant get it to go where you want and the Liquid Bearings stuff will rinse out with deoxit spray the next time you need to clean your pot. Silicone grease won't go away when you WANT it to.

 

[Alex SE]

you just have to be careful, if you lube TOO much, it can run through the shaft and contaminate your pot inside so it will have contact issues. The Liquid Bearing stuff has a nice needle tip and allows you to be very stingy with your lube as you can always add more but you can't take it back. The dielectric stuff is hard to get where you need it but do as you wish.

I agree regarding contamination. When using a grease (no matter which kind), the best way is to put a little of it in to the hole and then push a shaft thru it. That way all excess will come out of, not inside a potentiometer. Putting a grease on a shaft itself will do opposite.
And yes, silicone grease can do a hell inside electronics.