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gregz gregz is offline
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Default Scratchy volume control.

Peter Jason wrote:
On Mon, 4 Mar 2019 08:32:56 -0000 (UTC), gregz
wrote:

Jeff Liebermann wrote:
On Sun, 3 Mar 2019 08:52:10 -0000 (UTC), gregz
wrote:

Jeff Liebermann wrote:
On Thu, 28 Feb 2019 05:05:05 -0800 (PST), John-Del
wrote:

The only problem was that I had washed out the spooze that Sony
filled their controls with to make them feel like they were of
high quality and had a heft and weight to them. The customer
returned the TV a couple of days later because he didn't like
how the control had craploads of endplay and almost no drag as
it was rotated. We ordered a new control from Sony to make
the guy happy.

Maybe next time, try damping grease:
https://www.nyelubricants.com/damping-greases
I use a similar Nye grease for lubricating microscope gears[1], which
I've also used successfully for potentiometers and controls when
necessary. The stuff is outrageously expensive, but a small tube will
last a long time. You can get a 5 tube sample of different
viscosities fairly cheap from the company. However, I suspect
ordering a new control from Sony might be easier and cheaper.


[1] https://www.ebay.com/itm/292959265795

Been looking for something like damping grease.
Greg

If you're thinking of making your own, forget it. I tried and failed.
The trick is that it should not evaporate, not creep, and has to be
constant viscosity over a wide temperature range. If you read the
optics forums, you'll find that volatized thread lubricant, deposited
on the internal optics, is a really bad idea. This is not much of a
problem with electronic controls, except perhaps security cameras
inside waterproof domes. Creep is having the grease melt and drip all
over the front panel and the owners fingers. Constant viscosity is
needed to keep the controls from feeling loose when hot, and stuck
when cold. I gave up on making my own and over-paid for the real
stuff.

I suggest you NOT use silicone grease, which will creep and land on
the resistance material of a potentiometer or contacts of a switch.
Silicone grease is a good insulator and might produce a bad
connection, especially when mixed with dust and dirt. If this
happens, methinks the best cleaning solvents are hexane or Coleman
camp fuel which is about 25% hexane, and a soapy water cleanup.


For sliders that sit upright. The particular plastic rails seems
problematic. I tried everything I had including silicone damping fluid, not
on resistance part. The only thing that works is absolute clean, or Deoxit
after it's fully dried. I kept thinking some kind of thick stable grease.
Silicone with TFE nope. Got kit ordered.

Greg


What about the conducting stuff they use for CPUs
on motherboards?


My experience shows it dries up. Sure is messy.

Greg