Lubricate a pot

[Helmholtz]

..with an electro-conductive polymer...

This sounds interesting.
Can you measure a resistance after applying the stuff to a piece of paper?
None of the contact cleaners I ever tested showed any measurable conductivity (i.e. a resistance below 100M).
If a cleaner was conductive it would be problematic in high voltage or high impedance areas facilitating leakage and creepage.

[tedmich]

Stabilant 22 claims:

Stabilant 22 is an electrically active material which stays resident within a contact-pair, there enhancing conductivity without causing electrical leakage between adjacent contacts. Although Stabilant 22 does have a detergent action it is not sold as a cleaner, just as it has a good lubricant action but is not sold as a lubricant. Stabilant 22 is used to increase the reliability of contacts. Tenfold to one hundred-fold increases are not unusual. At the present time it is used in many different types of contacts, including card-edge connectors, D-type connectors, MIL-spec connectors, signal switches, etc. Stabilant 22 is an initially non-conductive amorphous-semiconductive polyoxyethylene-polyoxypropyline block polymer with a molecular weight of about 2800 that, when used in thin films between contacts, acts under the influence of the electrical field and switches to a conductive state. The electric field gradient at which this occurs is established during manufacture so that the material will remain normally non-conductive. Its switching speed is too slow to allow it to be used in the more traditional semiconductor applications; however, this means that signals at frequencies substantially above five cycles per hour will not be modulated by the switching characteristics of Stabilant 22. In its undiluted form at room temperature, Stabilant 22 has the viscosity of medium-weight motor oil, although it thins out with increasing temperature, starting to decompose into the two polymers it is formed from at about 240° Celsius. It has a very low vapor pressure and therefore there is no appreciable loss of material from evaporation. It has been in some applications for more than fifteen years without renewal, and it is probably safe to say that in the majority of cases, the equipment on which it is used will be retired as obsolescent before the Stabilant must be renewed.


All the data on this stuff suggests its basically BASFs Pluronic L-81 surfactant which costs $0.10 per mL and a transition from dielectric to conductive/semiconductor behavior sounds very questionable. If you like it and it "works" cool but the claims ("0.00139 Hz lower limit of conduction") look nuts.

[Tom Phillips]

Oh my!
I'm concerned about the low molecular weight.

[Mark Hammer]

The thing I just don't understand about it is this. If it is conductive, and I spread it on the surface of the resistive strip on a pot, why doesn't it conduct "sideways" (i.e., across the resistive strip)? Glad it doesn't. but perplexing nonetheless.

With respect to contact longevity, after application, I would imagine that depends on the extent of use of that control. Certainly today's 9mm mini pots can't be expected to have particularly long lives anyway. Most are sealed, such that cleaning or lubrication is essentially impossible. And my own experience is that the smaller the pot diameter, the crappier and more abrasive the wipers tend to be. Wipers on traditional 24mm pots are like a baby's bum, round and smooth. Wipers on smaller pots can resemble the old-fashioned "cow-catchers" on trains.

[Mars Amp Repair]

Thanks for all the replies. I have actually taken apart pots and lubricated them with Vasoline.

In my specific case, I determined the pot had a cracked wafer, so I replaced it; there was no need to lubricate a new pot.

Here's another old-guy anecdote from YEEEEEAAAARS ago.
As a teen, I worked for a tiny TV repair shop back in the early 70's. Some older TV's has what was called a 'Turret' tuner. Basically, when you turned the big channel select knob, it was internally turning a large barrel that housed individual 'turrets' or cards if you will that represented each local channel. They each also had the fine tuning coil for each channel that you could access from a front panel knob. The turrets had a number of contact points that connected to stationary fingers in the tuner assy.
ANYWAY, like any contacts over time they needed to be cleaned. My boss used Vaseline to do that job. He was so cheap that not only did he have me request paper towels from the customer, he also had me request the Vaseline towels to do the job!
In retrospect, I doubt I would have thought to use Vaseline, but I'm SURE I would NEVER request the customer let me use theirs!!!
As far as the efficacy of using Vaseline in a tuned circuit, I never had any issues arise from it, but If it were somehow to cause the frequency to drift, you always had the fine-tuning to compensate!
Things were pretty archaic compared to even 10yrs after that as far as technology goes. As I recall, most devices by the later 70's has closed loop circuits with varactor diodes, so no need for mechanical 'fine-tuning'.
Anyway, another old-guy anecdote!
Glen