Lubricant for pots?

Radio Shack sells a small white spray can with cleaner and lubricant. I've had good luck with it.

Bob

--
== All google group posts are automatically deleted due to spam ==

Try WD-40

Peter

"pawihte"

** Pots do not need lubricating.

How about you post a question properly for once ?

What is the actual problem with the pots ??

.... Phil

This is not about a problem with a particular pot. Many inexpensive carbon pots develop intermittent contacts and scratchy sounds in audio. This happens both with pots fitted in a product by a manufacturer and with pots bought from a shop. Some become defective within a couple of months of regular use, especially in a dusty environment and/or if they have dc current passing through them. Replacing them with better quality pots is not always an option. Flushing with a solvent usually makes them OK again for a while, but this also takes out the lubricant and makes the track wear out more quickly.

** Totally mangled nonsense - the track of a carbon ( or other) pot has no lubricant applied during manufacture.

Any lubricant that resided on the track would prevent operation - cos lubricants are insulators.

Rapidly evaporating solvents are rarely any use for fixing noisy pots while slow evaporating ones that leave a thin oil residue are very good at the job.

Also, rotary pots do not get " dust " inside them.

What actually causes all the trouble is a when a mix of fine carbon particles from the track and grease from the shaft bearing accumulate on the fingers of the two wipers and render them partially non conducting. Also, the metal to metal wiper contacts suffer from surface contamination by the moisture and sulphides in the air - a thin oily film helps prevent any recurrence of this. The oil must be thin that rotating the pot displaces all of it from the contact areas.

A mix of oil and petroleum solvent has a very low surface tension so easily travels by capillary action to cover all the insides of a pot.

There is a very famous product that fits the bill exactly ...... W something ......

One uses only a small amount ( a few drops) and then rotates the pot many times to help it do the trick - repeating the process only if necessary. If the pot is still noisy - replacement is the only option.

BTW

Some 100mm fader pots I looked at a week back did not respond to the above treatment - when opened up I found the finger contacts on the slider were worn completely away !!!

.... Phil

Maybe not within your experience, but some manufacturers certainly do apply lubricants on the track. As a hobbyist, I've opened up many varieties of vulume control type pots, both rotary and slide. I opened some of them when they were quite new and there's no time for the fine grease-like substance to migrate from the support mechanism to the tracks.

That's why I had to ask about suitable substances. Some of them were still working flawlessly with "grease" on the tracks when I opened them. In most cases, the lubricant had been pushed into a ridge right beside the wiper path.

So, if "a thin oil resude" works, why not some other lubricant?

They most certainly do. There are often enough gaps in the housing to let dust in.

As I said at the beginning, it is sometimes difficult to get a replacement of the same type. Gone are the days when most volume control pots were of about one-inch diameter, with a 1/4-inch steel shaft and eyelet solder tags, secured to a metal chassis with a nut.

I've come across such wear effects too, but that's not what I was talking about. What I did mention was that they wear more rapidly without lubricant.

"pawihte"

** Bollocks.

** Then there is NONE lubricating the conducting surfaces !!!!

You earlier claim is 100% bogus.

** Utter bollocks.

** Your problem.

** There can be NONE on the conducting surfaces.

Your thinking is totally irrational.

And you're an arrogant pig.

..... Phil

Not at the point of contact at the time of contact, at least not in enough thickness to prevent conduction.What about oil-filled switches and contactors, eh? The oil or grease simply gets squeezed out of the way at the point of contact and then flow in again.

At least you're consistent. Did mommy forget to give you your medicine again? Good. Don't ever change. You're good for comic relief.

"pawihte"

Your thinking is totally insane.

And you're a pig ignorant turd.

Drop dead.

..... Phil

I've been using WD 40 since the days of turret TV tuners without problems. But WD is a branded product . . . how about some light machine oil or kerosene?

[...]

Did someone already mention "contact cleaner" for this purpose?

Relay contacts, TV tuner contacts, and pot wipers. I still have my father's old can of De-Ox-Id, and it still works (heck, I'm impressed that it still has usalbe propellant ). When my old (c.1974) Kenwood stereo receiver's volume control picks up a little bit of scratchiness (erratic contact when rotating), one squirt cures it.

Frank McKenney

-- The ultimate result of shielding men from the effects of folly is to fill the world with fools. --Herbert Spencer, English Philosopher

-- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all)

I think you have that right. It wouldn't surprise me that the contact cleaners that "leave no residue" are less effective for that reason.

Particles rubbed off the pot as a cause are probably secondary to oxides on the contact fingers.

I have a lot of, way too many, old Tektronix scopes and plugins, some dating back to the all-tube days. The pots get noisy after a few decades on storage. A small spritz with contact cleaner - the RatShack stuff works fine - and a few good twists fixes them right up. If the back has openings, I spray it in there; if not, it can usually be blasted into the shaft bushing.

John

Thanks to those who posted helpful replies. It's been a long time since I had to bother with noisy pots. When I did such things regularly, contact cleaners were just things I read about in foreign magazines. I think they're available in local shops now. Anyway, the stuff I found inside pots were accumulated dust, lint and unidentified fuzz and grit that were sometimes so thick that I'd still prefer to open up the pot, wash it with a solvent and then apply the lubricant manually.

Back when I kit-built my radio control gear, the pots got lubricated with petroleum jelly (Vaseline, to violate your "no brand name" rule).

Don't blame me if you find a brand of pot that gets dissolved by it, though.

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

Vaseline is so common that I'll count it as generic. Thanks for the info.

Be careful, your poking a stick into Phyllis's cage. As you can see this aggravates the beast causing a fit of Tourettes. Communicate with caution!

I accept you did not want a brand name but some products have a very limited range of suppliers. Servisol was a good contact and pot cleaner years ago but I have been away from that area for too long to know if it still around.

Of course steel wool is still a very common POT cleaner.

John G.

My wife already told me that. But she uses it less often since she stopped using a wood-burning stove.