Noisy Switches

[Cursitor Doom]

has anyone got any tips as to how to deal with these? Some of the pots
and rotary switches I come across seem (at first sight at any rate) to be
fully encased and consequently very difficult (and some) to get any
lubricant into. I reckon there must be some old trick or knack I'm not
familiar with. Is there any alternative to removing them outright and
soaking them or drilling tiny holes in the casings to squirt lube in
through?

 

[pfjw@aol.com]

On Tuesday, November 22, 2016 at 4:39:35 PM UTC-5, Cursitor Doom wrote:

has anyone got any tips as to how to deal with these? Some of the pots
and rotary switches I come across seem (at first sight at any rate) to be
fully encased and consequently very difficult (and some) to get any
lubricant into. I reckon there must be some old trick or knack I'm not
familiar with. Is there any alternative to removing them outright and
soaking them or drilling tiny holes in the casings to squirt lube in
through?

I have this wonderful little device made from a bit of brass tubing, a threaded fitting soldered onto it and a small piston that seals with O-rings - almost like a very primitive syringe.

How it works: The threaded fitting has a small O-ring inside and is threaded onto the switch or pot until it seals. Lubricant is introduced and the piston inserted. By activating the piston, the lubricant is then forced around the shaft into the guts of the pot or switch.

Works like a charm. The tube is a few inches long to accommodate different shaft lengths, but one does not have to fill the thing. The piston (if made correctly) seals the tube so that the lubricant is directed into the pot. The pot just needs to face UP.

Peter Wieck
Melrose Park, PA

 

[Cursitor Doom]

On Tue, 22 Nov 2016 13:54:35 -0800, pfjw@aol.com wrote:

How it works: The threaded fitting has a small O-ring inside and is
threaded onto the switch or pot until it seals.

What thread are you talking about here? The one the shaft revolves inside
of that's used for securing the pot/switch to the front panel?? Can't see
how that would work. :-/

 

[Phil Allison]

Cursitor Doom wrote:

has anyone got any tips as to how to deal with these? Some of the pots
and rotary switches I come across seem (at first sight at any rate) to be
fully encased and consequently very difficult (and some) to get any
lubricant into. I reckon there must be some old trick or knack I'm not
familiar with. Is there any alternative to removing them outright and
soaking them or drilling tiny holes in the casings to squirt lube in
through?

** Drilling a small hole is your safest bet.

It always works and will not remove the grease packed into the shaft bearing and ruin the control's nice feel as with the other idea posted here.

FYI;

just serviced some early 60s UK made valve audio that used fully sealed, ganged pots for volume, balance, bass & treble.

Not a sign of noise in any of them.



..... Phil

 

On Tuesday, November 22, 2016 at 9:10:35 PM UTC-5, Michael Terrell wrote:

A guy named Bill Turner used to sell an injection tool of that sort,
and also sold oleic acid (which can be diluted in naptha to create
something a bit like the original Cramolin Red contact cleaner). I
don't think he's still in business, though.


Someone else now has the domain name for Turner's website.


--

Bill's health was always been nebulous since he started on the web. I think he's still alive, but with his eyesight being what it is and other health issues, he had to give up the hobby. Too bad. A very innovative guy who sold wares for barely more than it cost him, and he gave his knowledge freely.

 

[Dave Platt]

In article <o12lki$gvd$15@dont-email.me>,
Cursitor Doom <curd@notformail.com> wrote:

How it works: The threaded fitting has a small O-ring inside and is
threaded onto the switch or pot until it seals.

What thread are you talking about here? The one the shaft revolves inside
of that's used for securing the pot/switch to the front panel?? Can't see
how that would work. :-/

http://www.premierguitar.com/articles/a-pot-cleaning-miracle-1
mentions a somewhat similar device.

Consider the simple case - a hollow tube, with inside threads that
match those around the outside of the pot's bushing (the one you screw
the retaining nut onto). Screw this on, hold the pot with the tube
pointing upwards, and pour or spray a suitable cleaning solution into
the top of the tube. It flows down, and surrounds the pot's shaft
(which comes out through the bushing).

The shaft is not hermetically sealed to the bushing - it can't be.
There's always going to be a small gap between the outside of the
shaft, and the inside of the bushing... and the cleaning solution can
flow through this gap and into the inside of the pot.

For a "fully sealed" pot, this gap's going to be quite small - there
may be an O-ring seal inside, I suppose. So, you may need to
pressurize the cleaning solution to force it into the pot. That can
be done by forcing a piston of some sort into the tube, or by
attaching a syringe to the top of the tube (via a sealed cap) and
squirting/pressurizing that way, or etc.

A guy named Bill Turner used to sell an injection tool of that sort,
and also sold oleic acid (which can be diluted in naptha to create
something a bit like the original Cramolin Red contact cleaner). I
don't think he's still in business, though.

 

[Michael A. Terrell]

Dave Platt wrote:

In article <o12lki$gvd$15@dont-email.me>,
Cursitor Doom <curd@notformail.com> wrote:

How it works: The threaded fitting has a small O-ring inside and is
threaded onto the switch or pot until it seals.

What thread are you talking about here? The one the shaft revolves inside
of that's used for securing the pot/switch to the front panel?? Can't see
how that would work. :-/

http://www.premierguitar.com/articles/a-pot-cleaning-miracle-1
mentions a somewhat similar device.

Consider the simple case - a hollow tube, with inside threads that
match those around the outside of the pot's bushing (the one you screw
the retaining nut onto). Screw this on, hold the pot with the tube
pointing upwards, and pour or spray a suitable cleaning solution into
the top of the tube. It flows down, and surrounds the pot's shaft
(which comes out through the bushing).

The shaft is not hermetically sealed to the bushing - it can't be.
There's always going to be a small gap between the outside of the
shaft, and the inside of the bushing... and the cleaning solution can
flow through this gap and into the inside of the pot.

For a "fully sealed" pot, this gap's going to be quite small - there
may be an O-ring seal inside, I suppose. So, you may need to
pressurize the cleaning solution to force it into the pot. That can
be done by forcing a piston of some sort into the tube, or by
attaching a syringe to the top of the tube (via a sealed cap) and
squirting/pressurizing that way, or etc.

A guy named Bill Turner used to sell an injection tool of that sort,
and also sold oleic acid (which can be diluted in naptha to create
something a bit like the original Cramolin Red contact cleaner). I
don't think he's still in business, though.

Someone else now has the domain name for Turner's website.


--
Never piss off an Engineer!

They don't get mad.

They don't get even.

They go for over unity! ;-)

 

[gregz]

"Michael A. Terrell" <mike.terrell@earthlink.net> wrote:

Dave Platt wrote:
In article <o12lki$gvd$15@dont-email.me>,
Cursitor Doom <curd@notformail.com> wrote:

How it works: The threaded fitting has a small O-ring inside and is
threaded onto the switch or pot until it seals.

What thread are you talking about here? The one the shaft revolves inside
of that's used for securing the pot/switch to the front panel?? Can't see
how that would work. :-/

http://www.premierguitar.com/articles/a-pot-cleaning-miracle-1
mentions a somewhat similar device.

Consider the simple case - a hollow tube, with inside threads that
match those around the outside of the pot's bushing (the one you screw
the retaining nut onto). Screw this on, hold the pot with the tube
pointing upwards, and pour or spray a suitable cleaning solution into
the top of the tube. It flows down, and surrounds the pot's shaft
(which comes out through the bushing).

The shaft is not hermetically sealed to the bushing - it can't be.
There's always going to be a small gap between the outside of the
shaft, and the inside of the bushing... and the cleaning solution can
flow through this gap and into the inside of the pot.

For a "fully sealed" pot, this gap's going to be quite small - there
may be an O-ring seal inside, I suppose. So, you may need to
pressurize the cleaning solution to force it into the pot. That can
be done by forcing a piston of some sort into the tube, or by
attaching a syringe to the top of the tube (via a sealed cap) and
squirting/pressurizing that way, or etc.

A guy named Bill Turner used to sell an injection tool of that sort,
and also sold oleic acid (which can be diluted in naptha to create
something a bit like the original Cramolin Red contact cleaner). I
don't think he's still in business, though.


Someone else now has the domain name for Turner's website.

Sometimes I use the red nozzle against seams, and often gets inside enough
to do the job. Sprays have them, WD40, CRC 2-26, Deoxit. A little alcohol
or naphtha mixed with oleic acid gets into cracks.

Greg

 

[Jeff Layman]

On 23/11/16 00:50, Phil Allison wrote:

Cursitor Doom wrote:

has anyone got any tips as to how to deal with these? Some of the pots
and rotary switches I come across seem (at first sight at any rate) to be
fully encased and consequently very difficult (and some) to get any
lubricant into. I reckon there must be some old trick or knack I'm not
familiar with. Is there any alternative to removing them outright and
soaking them or drilling tiny holes in the casings to squirt lube in
through?


** Drilling a small hole is your safest bet.

It always works and will not remove the grease packed into the shaft bearing and ruin the control's nice feel as with the other idea posted here.

FYI;

just serviced some early 60s UK made valve audio that used fully sealed, ganged pots for volume, balance, bass & treble.

Not a sign of noise in any of them.



.... Phil

What make? Can reliability be assumed for any make?

Back in 1972 I bought a Ferrograph 307Mkii amp. Very good machine for
the time, but after 18 months I had to replace the volume control
(concentric pots) as it had become noisy on rotation. A few years later
in 1976 I bought a really cheap Hong Kong made LW/MW/VHF transistor
radio. Within a year the wave-change switch was very unreliable despite
not being used much. But, the on/off-volume control has been perfect for
over 40 years. I reckon I've turned that radio on/off, and rotated that
pot, over 15000 times during that period.

--

Jeff

 

[Phil Allison]

Jeff Layman wrote:

** Drilling a small hole is your safest bet.

It always works and will not remove the grease packed into the
shaft bearing and ruin the control's nice feel as with the other
idea posted here.

FYI;

just serviced some early 60s UK made valve audio that used fully
sealed, ganged pots for volume, balance, bass & treble.

Not a sign of noise in any of them.



What make? Can reliability be assumed for any make?

** Made in the UK, in the early 60s, installed in a Rogers Cadet 2 stereo pre-amp.

Exceptional longevity in service is the result of very good design, not some half baked notion called "reliability".



..... Phil

 

[Adrian Caspersz]

On 26/11/16 08:04, Jeff Layman wrote:

On 23/11/16 00:50, Phil Allison wrote:

FYI;

just serviced some early 60s UK made valve audio that used fully
sealed, ganged pots for volume, balance, bass & treble.

Not a sign of noise in any of them.



.... Phil

What make? Can reliability be assumed for any make?

Back in 1972 I bought a Ferrograph 307Mkii amp. Very good machine for
the time, but after 18 months I had to replace the volume control
(concentric pots) as it had become noisy on rotation. A few years later
in 1976 I bought a really cheap Hong Kong made LW/MW/VHF transistor
radio. Within a year the wave-change switch was very unreliable despite
not being used much. But, the on/off-volume control has been perfect for
over 40 years. I reckon I've turned that radio on/off, and rotated that
pot, over 15000 times during that period.

Some controls can be made noisy by a leak of DC from somewhere. Bad Caps?

--
Adrian C