ruck@sphere.UUCP (John R Ruckstuhl Jr) (08/17/90)
Someone suggested cleaning pins of a connector inside a personal computer, and applying ?dielectric grease? to the pins before reassembly to prevent the connections from degrading quickly. (There is a connector in the AT&T UNIX PC that has been observed to be susceptible to dirty, poor connections, responsible for a ?myriad? of problems). Would readers please comment on this practice of preventative medicine? What is the substance, should it be used, and where is it available? Since I don't see this substance widely used, there must be some negative aspects of such a practice. I !have! seen a white grease used on the connections in the hostile environment of my automobile headlights. Also, I have seen people spray WD40 on connectors for similar purposes. What residues does this WD40 leave (and are they both conductive and protective)? If these people are misguided, what would you recommend to them for recovering from grease-coated or WD40-sprayed connector pins? Thank you. Best Regards, ruck. -- John R Ruckstuhl, Jr ruck%sphere@cis.ufl.edu, sphere!ruck University of Florida ruck@cis.ufl.edu, uflorida!ruck
whit@milton.u.washington.edu (John Whitmore) (08/17/90)
In article <312@sphere.UUCP> ruck@sphere.UUCP (John R Ruckstuhl Jr) writes: >Someone suggested cleaning pins of a connector inside a personal >computer, and applying ?dielectric grease? to the pins before >reassembly to prevent the connections from degrading quickly. >(There is a connector in the AT&T UNIX PC that has been observed to be >susceptible to dirty, poor connections, responsible for a ?myriad? of >problems). There are a number of contact improvers on the market; Cramolin, Tweek, and Blue Stuff are three I have heard of. I've used Blue Stuff; it fixed the selector switches in an old Tek 453 'scope after the local technician pronounced the problem hopeless-and dumped his 453 for a new machine. I have heard that Tweek is a liquid semiconductor; nonconducting as a film, but when a thin layer is stressed with a high field (probably microvolts per meter) it turns conductive. The chemical treatments work. Beware of switch CLEANERS, which often cause trouble by washing grease from the shaft into the contacts. For connectors, a good cleaner (usually Freon TF) is recommended. Alternately, soapy water/distilled water rinse/compressed air blow-dry will do an adequate cleaning job; some amateur radio rigs have been restored by simply putting them in the XYL's dishwasher... Go to an electronics parts store (preferably an industrial outfit, not Radio Shack) and ask at the chemical counter. >What residues does this WD40 leave (and are they both conductive and >protective)? WD-40 works OK on high-voltage circuits that have moisture problems, because it is detergent enough to stick to most surfaces and displaces the moisture. WD-40 is mainly kerosene, leaves little residue, and is ONLY good for a quick fix (getting a car started after the distributor has gotten wet). WD-40 is not conductive, but if the voltage is high enough, a thin film doesn't stop the current. John Whitmore
thad@cup.portal.com (Thad P Floryan) (08/17/90)
ruck@sphere.UUCP (John R Ruckstuhl Jr) in <312@sphere.UUCP> writes:
Someone suggested cleaning pins of a connector inside a personal
computer, and applying ?dielectric grease? to the pins before
reassembly to prevent the connections from degrading quickly.
(There is a connector in the AT&T UNIX PC that has been observed to be
susceptible to dirty, poor connections, responsible for a ?myriad? of
problems).
Would readers please comment on this practice of preventative medicine?
What is the substance, should it be used, and where is it available?
Since I don't see this substance widely used, there must be some
negative aspects of such a practice. I !have! seen a white grease used
on the connections in the hostile environment of my automobile
headlights.
Also, I have seen people spray WD40 on connectors for similar purposes.
What residues does this WD40 leave (and are they both conductive and
protective)?
"Holy Bat Guano, Batman!" You do NOT want to put any kind of "white grease"
or WD40 on your computer's connections or connectors. The correct product is
CRAMOLIN.
For some general info about Cramolin, get the September 1990 issue of
POPULAR ELECTRONICS, and look at the "Gizmo" insert's pages 3 and 4. This
is RECOMMENDED READING, especially for computer use.
I've included (below) an extract of some of the applications of Cramolin
from my own experience and from others. The stuff is incredible; it's an
anti-oxidant, non-conducting lubricant.
Regarding WD40, though I use it for things like freeing stuck hinges on
my yard equipment, you do NOT want to use it for anything serious. Per
contacts with the US Navy, I've been informed that WD40 is proscribed
since it promotes rust (it's hydroscopic (hygroscopic? (dunno, my dictionaries
are still in storage)) ... it attracts water).
Back to Cramolin: that's the stuff you put on coin-silver switch contacts for
use in 1 GHz oscilloscopes, on silver contacts for use for premium audio
equipment, even on gold contacts and fingers in computer and medical stuff.
The one incident that convinced me years ago was the story of one AC power
switch mfd. by Cherry; it was originally UL rated at 1 Amp, and after an
application of Cramolin during manufacturing the UL re-rated the same switch
at 5 Amps. My own experiences with the (crap) Molex connectors as used in
lots of computer equipment bear out the efficacy of Cramolin. Get it!
Thad
Thad Floryan [ thad@cup.portal.com (OR) ..!sun!portal!cup.portal.com!thad ]
-------------------- begin enclosed material
[ the following is extracted from one of my postings last year (1989)
concerning mono-molecular lubricants such as would be used in disk drives.
To prove a point (and the postings and email I have on file concerning this
is humongous), I referenced the use of Cramolin, which follows: ]
And now, to bring everyone up to date with modern chemistry and its marvels, an
d
though I'm fully aware this is NOT the chemical lubricant used on HD platters,
I
would like to cite just ONE lubricant (of many I use) whose mono-molecular
layering (and recommended application with a "rag") is integral and fundamental
to its efficient use: Cramolin (tm).
Cramolin is produced by Caig Laboratories, Inc.; 1175-O Industrial Avenue;
Escondido, CA 92025-0051; ph: 619/743-7143. The Cramolin product is popularly
known as an "anti-oxidant lubricant" and is used on precision IC sockets, gold
plated connectors, switch contact points, coin-silver collector rings in space
gyroscopes, avionics, test labs, marine electronics, high-end audio equipment,
etc. by companies such as:
American Airlines, American Broadcasting Co., Ampex Co., AT&T, Audio Research
Corp., Bell & Howell, Bell Telephone Labs, Bendix Corp., Boing Co., Capitol
Records, Cherry Electrical Products, Continental Telephone, Cutler Hammer Inc.,
Dolby Labs, Dow Chemical, E.I. DuPont de Nemours, Exxon Co., General Dynamics,
General Electric Co., General Motors Corp., Grumman Aerospace Corp., GTE Corp.,
Hazeltine Corp., Hewlett-Packard, Hughes Aircraft Co., IBM Corp., ITT Corp.,
Jet Propulsion Labs, Litton Industries, McDonnell Douglas Corp., McIntosh Labs,
3M, Magnavox Co., Motorola Inc., Nakamichi Corp., Pratt & Whitney Aircraft,
RCA Corp., Rockwell International, Singer, Sperry Gyroscope Div., Sylvania,
Texas Instruments, TRW, Inc., US Defense Department, Western Electric Co., Inc.
,
Yamaha Corp., and others.
From Caig Laboratories' Service Bulletin SB-4, reprinted without permission:
"Suggested methods of application for Cramolin Red/Blue fluid
1. take a clean linen cloth -- soak approximately a 4"x4" square cloth -- and
spray until it gets a light pink color (R) or light blue (B).
First test to see if cloth has been saturated with enough Cramolin Fluid by
pressing a corner of the cloth against a clean dry glass specimen slide.
Look at the spot on the glass under reflected light. You should be able to
see a small oily looking spot. If the spot is too difficult to see, then
saturate the cloth slightly more. If the spot appears heavy or runny, then
the cloth is oversaturated.
2. ... continues for two pages ....
"
The REASON one has to look at the material on the specimen slide by reflected
light is BECAUSE the stuff migrates and forms a MONO-molecular layer that you
will NOT see by direct observation. The cautions regarding too little and too
MUCH depend on human discretion and "experience."
-------------------- end of included extractdplatt@coherent.com (Dave Platt) (08/18/90)
In article <312@sphere.UUCP> ruck@sphere.UUCP (John R Ruckstuhl Jr) writes: > Someone suggested cleaning pins of a connector inside a personal > computer, and applying ?dielectric grease? to the pins before > reassembly to prevent the connections from degrading quickly. > (There is a connector in the AT&T UNIX PC that has been observed to be > susceptible to dirty, poor connections, responsible for a ?myriad? of > problems). > > Would readers please comment on this practice of preventative medicine? > What is the substance, should it be used, and where is it available? I'm not sure I'd use dielectric grease, if that's what I'm referring to when I think of "heat-sink grease". This stuff is fairly thick, and might not make the best contact-preserver. > Also, I have seen people spray WD40 on connectors for similar purposes. > What residues does this WD40 leave (and are they both conductive and > protective)? The residues are (I believe) a light petroleum oil. They are themselves almost certainly _not_ conductive... you wouldn't want them to be! Any conductive lubricant (e.g. graphite) would short out the connector! > If these people are misguided, what would you recommend to them for > recovering from grease-coated or WD40-sprayed connector pins? There are several products which might do the trick for you. Miller-Stevenson makes a "Connector cleaner" spray... a combination of Freon TA and a polypheny ether lubricant which both lubricates and preserves contact surfaces. M-S is updating their product line to use hydrochlorofluorocarbons which are less environmentally damaging than older CFCs. You may be able to find this stuff at a decent electronics-supply store. Another useful product is Cramolin. It's an oily liquid... two liquids, actually. The red stuff is a contact cleaner... you brush a bit onto the contacts, scrub them with the bristle-brush included with the kit, wait a few minutes, and then wipe it off. The blue stuff is a contact preservative... brush on a _very_ small amount with a Q-tip, and it'll keep the contacts from tarnishing and corroding. Cramolin is sold in small (1/2 oz) bottles... a set of two will probably cost you $15 or so (that's a wild guess re today's prices... I bought my set a decade ago and haven't used more than a tenth of it).