Any opinions on the best way to clean scratchy switches and
potentiometers?

kevin wrote:
Any opinions on the best way to clean scratchy switches and
potentiometers?

Cramolin Rot and Cramolin Blau, if you can find it.

Caig stuff if you can't.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Fri, 31 Oct 2003 07:14:21 -0700, kevin
wrote:

Any opinions on the best way to clean scratchy switches and
potentiometers?

I'm using MG Chemicals "Super Contact Cleaner with Poly Phenyl Ether".
http://www.mgchemicals.com/products/801b.html
It seems to do a good job of protecting switch and connector contacts,
and it's available at most electronic parts suppliers.
Mike T.

"Scott Dorsey" wrote in message
...
kevin wrote:
Any opinions on the best way to clean scratchy switches and
potentiometers?

Cramolin Rot and Cramolin Blau, if you can find it.

Caig stuff if you can't.
--scott

Is Cramolin still made ?

Caig Cailube for pots.

geoff

kevin wrote:

Any opinions on the best way to clean scratchy switches and
potentiometers?

I find it most cost effective to replace them. Cleaning only delays
the inevitible and you'll again be inside the device sooner or later.

--
================================================== ======================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
| - The Who, Bargain

Geoff Wood -nospam wrote:

Is Cramolin still made ?

Yes, www.cramolin.de. They don't seem to have any US distribution of
any sort, though.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Yes, www.cramolin.de. They don't seem to have
any US distribution of any sort, though.

You mean Caig's red and blue stuff isn't Cramolin?

Geoff Wood wrote:
Is Cramolin still made ?

"Scott Dorsey" wrote ...
Yes, www.cramolin.de. They don't seem to have any
US distribution of any sort, though.

It appears that they are owned by Illinois Tool Works (who
also own Chemtronics, which isn't a good sign.)

Their list of products looks more like Chemtronics' and no
mention of "Rot" or "Blau". And their Distributor web page
is 404-Not found.

"kevin" wrote in message
...
Any opinions on the best way to clean scratchy switches and
potentiometers?

The most effective way I know is the way we did it on Nuclear Submarines
when the pots would get noisy in the instrumentation. We had a tool made of
brass that we would fill with pure grain alcohol (try finding that on the
street) and then the tool would screw down over the threads on the pot
shaft. At that point we would push a plunger on the tool and it would force
the alcohol down between the pot's shaft and the sleeve and then blow out
onto the resistive element. Kind of a squirt gun.

We were told that the reason for this is that corrosion and dirt would find
its way between the pot shaft and the sleeve and that too would cause noise.

Whatever, the pots on the instruments were always being adjusted and we
rarely had to replace one. Maybe one a year or so.

In article writes:

You mean Caig's red and blue stuff isn't Cramolin?

Not the original formula, either for the stuff, the solvent, or the
propellant. But it works just as well as far as most people can tell.


--
I'm really Mike Rivers - )

In article writes:

We had a tool made of
brass that we would fill with pure grain alcohol (try finding that on the
street) and then the tool would screw down over the threads on the pot
shaft.

I haven't checked in several years, but we used to be able to buy pure
(190 proof - alcohol absorbs water when it's opened to the air) grain
alcohol in the Virginia state liquor stores.

it would force
the alcohol down between the pot's shaft and the sleeve and then blow out
onto the resistive element. Kind of a squirt gun.

We were told that the reason for this is that corrosion and dirt would find
its way between the pot shaft and the sleeve and that too would cause noise.

I expect that the assembly was behaving like a semiconductor,
detecting RF (like a crystal set) and introducing that into the
circuit. I remember seeing one of those pot cleaning tools many years
ago. I wonder if they're still made?



--
I'm really Mike Rivers - )

In article ,
William Sommerwerck wrote:
Yes, www.cramolin.de. They don't seem to have
any US distribution of any sort, though.

You mean Caig's red and blue stuff isn't Cramolin?

Hasn't been for years. Caig claims that they stopped making Cramolin
under license because of EPA regulations; Cramolin says they stopped allowing
Caig to make it because they were adulterating the product. I don't know
who to believe.

But the current Caig line is very much different than the old Cramolin.
Doesn't evaporate as quickly and doesn't smell the same at all.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Richard Crowley wrote:
Geoff Wood wrote:
Is Cramolin still made ?

"Scott Dorsey" wrote ...
Yes, www.cramolin.de. They don't seem to have any
US distribution of any sort, though.

It appears that they are owned by Illinois Tool Works (who
also own Chemtronics, which isn't a good sign.)

Their list of products looks more like Chemtronics' and no
mention of "Rot" or "Blau". And their Distributor web page
is 404-Not found.

I think the old "Rot" is now called Contaclean, and the old "Blau"
is called Protectant. They do not appear to have any US distributor
at all.
--scott





--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Scott Dorsey wrote:

In article ,
William Sommerwerck wrote:
Yes, www.cramolin.de. They don't seem to have
any US distribution of any sort, though.

You mean Caig's red and blue stuff isn't Cramolin?

Hasn't been for years. Caig claims that they stopped making Cramolin
under license because of EPA regulations; Cramolin says they stopped allowing
Caig to make it because they were adulterating the product. I don't know
who to believe.

But the current Caig line is very much different than the old Cramolin.
Doesn't evaporate as quickly and doesn't smell the same at all.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

They may both be correct. Caig tries to reformulate it to make it less
objectionable to the EPA. Cramolin says to Caig, make the real stuff or
don't make it under that name.

--Dale

They may both be correct. Caig tries to reformulate it to make it less
objectionable to the EPA. Cramolin says to Caig, make the real stuff
or don't make it under that name.

Caig no longer calls it Cramolin.

Mike Rivers wrote:

In article writes:

We had a tool made of
brass that we would fill with pure grain alcohol (try finding that on the
street) and then the tool would screw down over the threads on the pot
shaft.

I haven't checked in several years, but we used to be able to buy pure
(190 proof - alcohol absorbs water when it's opened to the air) grain
alcohol in the Virginia state liquor stores.


It is available from the supply houses. Get pharmaceutical grade ethanol.
Before you open the container it is 99.something pure. When I was in the
navy, we ordered it on the ship, it came in five gallon cans. No matter how
many locks and seals we put on it in the flammable liquid locker, it was
amazing how much of it evaporated out though the sealed cap.

--Dale

someone wrote:

"kevin" wrote in message
...
Any opinions on the best way to clean scratchy switches and
potentiometers?

The most effective way I know is the way we did it on Nuclear Submarines
when the pots would get noisy in the instrumentation. We had a tool made of
brass that we would fill with pure grain alcohol (try finding that on the
street) and then the tool would screw down over the threads on the pot
shaft. At that point we would push a plunger on the tool and it would force
the alcohol down between the pot's shaft and the sleeve and then blow out
onto the resistive element. Kind of a squirt gun.

We were told that the reason for this is that corrosion and dirt would find
its way between the pot shaft and the sleeve and that too would cause noise.

Whatever, the pots on the instruments were always being adjusted and we
rarely had to replace one. Maybe one a year or so.

For that matter, if you're going to the trouble to replace 'em,
just desolder the pot, disassemble it and *really* clean it with
high concentration isopropyl and a q-tip. I've never actually had
to replace a pot since discovering this.

--
Les Cargill

On 1 Nov 2003 09:00:50 -0500, (Scott Dorsey) wrote:


I think the old "Rot" is now called Contaclean, and the old "Blau"
is called Protectant. They do not appear to have any US distributor
at all.
--scott

"Rot" and "Blau"? -- Interesting, the German Kontakt Chemie offers
for decades three types of contact cleaners which are best to be used
together in a sequence. The "Kontakt WL" is a freon-based blend which
is used the first for washing away grit etc. Then "Kontakt 60", the
red one, which is used for the cleaning. It may left a greenish
copper-oxide like residue which acc. to the manufacturers was
passivized oxides and does no harm.For longer protection and
lubrication it's the blue "Kontakt 61". It seems pretty close to what
you are describing, Scott.

I've found this site with a description. It seems that the Kontakt
Chemie company has been sold to an another one:

http://www.mantech.co.za/KONTAKT/kc-02.HTM

Edi Zubovic, Crikvenica, Croatia