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Troubleshooting Professional Magazine

 
Volume 7 Issue 3, Summer, 2003
Lubricating Electronic Contacts
Copyright (C) 2003 by Steve Litt. All rights reserved. Materials from guest authors copyrighted by them and licensed for perpetual use to Troubleshooting Professional Magazine. All rights reserved to the copyright holder, except for items specifically marked otherwise (certain free software source code, GNU/GPL, etc.). All material herein provided "As-Is". User assumes all risk and responsibility for any outcome.


Steve Litt is the author of Troubleshooting Techniques of the Successful Technologist and Rapid Learning: Secret Weapon of the Successful Technologist.

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Be not afraid of greatness: some are born great, some achieve greatness, and some have greatness thrust upon them. -- William Shakespeare

CONTENTS

Editor's Desk

By Steve Litt
Some are born with knowledge, some achieve knowledge, and some have knowledge thrust upon them. Surely I'm the latter.

Take my discovery of "Litt's Overheating Hypothesis". It's been known as long as there have been cars, but only by a few. Unfortunately, the majority of automotive technicians appear not to understand that absense of water in the oil or steam out the exhaust does not exhonorate the head gasket. The majority of auto techs don't realize that a bad head gasket can be the causeof overheating, as well as the effect.

I discovered this after a grouping of emailed strange overheating symptom descriptions. The group was too large to write off as "defective customer", so I investigated, and the investigation led to the role of breached head gaskets in cyclical overheating and unexplained coolant loss. Knowledge was thrust upon me.

A few months ago knowledge was once again thrust on me. It started with what appeared to be a simple keyboard failure, then proceded through a jungle of strange intermittents, ending up in a land I knew little about -- electronic contact lubrication.

We all know electronic contacts can corrode or otherwise fail. We all know that such failures produce hard to diagnose intermittents. What isn't such common knowledge is that such failures can be greatly reduced by lubrication of electronic contacts, and that such lubrication can be done quickly, safely and effectively, making it an ideal item for Universal Troubleshooting Process Step 5: General Maintenance.

This issue of Troubleshooting Professional Magazine discusses electronic contact lubrication -- its value, its operation, hints on how to best accomplish it, its costs, and the possible costs if it is not done. So kick back, relax, and remember -- if you're a Troubleshooter, this is your magazine.
Steve Litt is the author of "Troubleshooting Techniques of the Successful Technologist".  Steve can be reached at Steve Litt's email address .

My Story

By Steve Litt

I originally learned to lubricate electrical contacts while fixing an intermittent problem with my son's keyboard. If you'd like details of that story (and much more great information), you can read it in my book Twenty Eight Tales of Troubleshooting, in a story called "The Phantom Keyboard Killer."

My Daughter's Intermittent

"Daddy -- my computer screen looks funny."

My daughter's voice. My two daughters share an old Celeron 233 Windows machine, and the video had gone on the fritz. The picture was wavy and jumbled, looking quite a bit like an overdriven monitor, but a little different. Rebooting didn't help.

Their monitor is a circa 1991 Viewsonic that I've been expecting to go any time now. I swapped out the monitor, confidently expecting the symptom to disappear. I almost fainted when the exact same symptom showed up on the known good monitor. Not having time, I put it aside, vowing to swap out the video card as soon as I could.

My earlier electronic lubrication discovery happened in the intervening time, and I got to wondering whether it could be a connector problem, and if so, would WD40 solve it? So when I got a little time, I went back, powered up the computer, and whoops -- the symptom had gone away.

With connector problems so fresh in my mind, I wiggled the video card while the computer was on, and was rewarded with occasional horizontal stripes across the monitor. Great -- we have a physical intermittent, probably in the video card or its connector.
WARNING

Wiggling cables, cards and other connections inside a running computer carries a chance of consequential damage. Before performing such activities you must balance the value of the time saved by these activities (likely hours, possibly days) against the possible damage to motherboard and other components.

In my 10 years of using such techniques in running computers, those activities have never caused consequential damage, but there's always a chance.


I powered down, removed the video card, and lightly applied WD40 to the gold fingers of the card, and to the IDE connector on the motherboard. Then I inserted and removed several times to knock off any oxide, and reinstalled the video card. I also used WD40 on the monitor cable connector and inserted/removed several times.

I booted, and moved the video card, and there were no horizontal stripes. Wonderful. So I pushed the video card harder, and everything was fine. But when I pushed it with extreme force, the computer rebooted. Was I dealing with multiple root causes?

I removed every daughterboard and used the WD40 technique. I used the WD40 technique with all IDE and floppy cables. I used it with the SDRAM stick and with the cables to the serial and parallel connectors. Then I powered on, dropped the computer an inch, and boom, it froze.

Several reboot cycles with physical manipulation of individual components led me to believe the problem was in the SDRAM or its connector. Pushing sideways on the SDRAM stick with a couple ounces of pressure caused the computer to hang. Having already WD40'ed the stick and its motherboard based connector, I figured it had to be either a defective stick or defective board based connector. I swapped the stick first, and bang, the symptom went away. I could smack the computer around as much as I wanted, and no hang, no reboot.

WARNING

Dropping or "smacking around" a running computer can cause damage to the hard disks. Unless it's very important to verify the fix of a physical intermittent before returning the system to service, it might be best to limit physical intermittence testing to wiggling individual cards and connectors -- an activity with a much lower likelihood of consequential damage.

So the WD40 technique had cured an intermittent video problem, and proven itself an able general maintenance technique.

Bridges Burned

My mind went back to all the intermittent parts I've thrown away over the years. Tens of IDE cables, video cards, network cards, and even a couple motherboards. One in particular was a Chaintech mobo with a Celeron 333 -- an ancient warrior Linux box I'd improved over time until it had 512 MB of RAM, and small footprint software that made it move right along. But I used it as an Installfest machine and a demonstration machine, so it spent a lot of time being transported.

Most times after it was transported, it would fail to boot. Then you'd need to replace the video card, or sometimes the network card. Transport again, replace again. Finally I learned I could merely remove and reseat, but as time went on even that became iffy. Dealing with its intermittence became intolorable, so a few months ago I decommissioned it and spent $400.00 to get a new, Athlon based computer with an Asus motherboard -- the one that ended up with keyboard malfunctions.

Now I wondered if the problem was as simple as fretting corrosion, and the solution was as simple as lubricant. Several months later I re-commissioned the Chaintech, but it was intermittent in spite of lubrication. Lubrication isn't a cure for all intermittents.

Search for the Holy Lubricant

My posts to the Linux Enthusiasts and Professionals list included a call for opinions on the best lubricant for the purpose. Almost instantly, WD40 was ruled out as an ongoing operation -- it's parafin based. Nobody wants waxy buildup in their connectors.

LEAP opinion and my research indicates that the Cadillac of the industry is a product called Stabilant 22. Stabilant 22 is initially an insulator so it won't short components, but when trapped between mated parts it becomes a conductor, producing a connection of similar quality to soldering. Unfortunately, it's fabulously expensive.

On the other end of the price spectrum was the suggestion of automatic transmission fluid, which is very slippery, fairly thin, and contains detergent. At $1.49 per quart, it would cost a computer store less than a dime a week to lubricate every card and cable on every computer sold. For a home business, a quart would be a lifetime supply.

In the middle was a gun oil called Break-Free CLP, which can be bought at Walmart. Another suggestion was dialectric grease, but I'd imagine a viscuous grease would be harder to spread throughout mating surfaces.

And of course, there's the old standby -- lubricated contact cleaning sprays like I used at Pacific Stereo in the 1980's.

Opportunities Abound

The Stabilant 22 website contains several stories of people who assumed they had software glitches, and after Stabilant 22 was applied, their "software glitches" went away. Connector lubrication is one of the best kept secrets of the computer industry, and given the industry's problems with intermittents, it's sorely needed.

I've incorporated connector lubrication into my computers' preventive maintenance routines. It's only been a couple months, but I have a feeling I'm experiencing a lot less intermittents, and throwing away a lot less parts.

Try it yourself. Here are some great applications:
Steve Litt is the creator of the Universal Troubleshooting Process.  Steve can be reached at Steve Litt's email address.

Anatomy of an Electronic Corrosion Problem

By Steve Litt
How often does your computer "hang", "freeze", or "crash"? How often do you assume it's a software problem? How often do you blame the problem on Bill Gates (or Linus Torvalds or Steve Jobs)? Is that a valid assumption?

Perhaps not. Most of us have experienced intermittent operating system installation problems on certain hardware, and sometimes found that once the installation was complete, the computer was useful, if a little more "crashy" than most. A hardware problem can convert a one to a zero or vice versa, and the corrupted number is interpeted as either bad data, a bad pointer, or a bad op-code. Looks like a software problem, but the root cause is hardware.

Overclockers experience this on a regular basis, using heat sink compound and other techniques to lower the CPU temperature. I often recommend temporarily underclocking a computer by 20% to rule out temperature and timing problems.

Another source of hardware problems is contact resistance, which can make a one look like a zero or vice versa, or make it indeterminant. If zero is 0 volts and one is 3.2, what is 1 volt?

One frequent problem with resistive contacts is that the resistance is not linear with respect to voltage. Larger voltages tend to break down the corrosion, lowering the resistance, but lower voltages encounter a much higher resistance. Viewed with a sine wave, corrosion resistance causes crossover distortion:

Here, the blue is the current forced by a sinewave voltage through an absolutely clean connection, where any circuit resistance is in series with the connection.

The red is the current forced by the sinewave voltage through a corroded connection, where the connection's resistance is significant compared to any series resistance. Because the resistance increases at lower voltages, lower voltages force proportionally less current than the higher voltages. leading to the flat spots at lower voltages.

Note that the diagram to the right is exaggerated to make a point. In real life, the flat spots would probably be shorter, and would be sloped or curved. But you get the idea -- bigtime distortion that can lead to data degradation in digital applications.
 Crossover distortion with sine wave


More significantly, dirty contacts can distort the edges of square waves, creating dull, curved edges, or even harmonic spikes. The following are pictures of a clean square wave produced by a clean connector, and a dirty square wave produced by running a square wave voltage through a dirty connector:
The dirty squarewave diagram to the right is typical of that produced by a dirty connector in a high frequency application. Such distorted squarewaves can be either rounded on one or more edges, as in the left edge of the dirty square wave diagram, or spiky on one or more edges, as shown on the right edge of the diagram, or even a combination. A rounded edge could corrupt data, and the spiky edge is almost guaranteed to do so.

The bottom line is that keeping connectors clean is vital to keeping your computer's data and operations accurate.
 Clean square wave
 Dirty square wave
Clean square wave
 Dirty square wave

As mentioned previously in this document, when mating tin surfaces are subject to vibration, the vibration scrapes off oxides that would normally inhibit additional oxidation. Then the raw metal is further oxidized, while the scraped oxide is pressed between the mating surfaces. As this process continues, current has more and more oxide to go through, and the distortions detailed in this article occur.

Computers vibrate. That's what they do. Every fan in the computer contributes to vibration.

Lubricating connectors greatly reduces the scraping effect, thereby reducing corrosion buildup.

Fretting corrosion, and electronic connectors in general, are a highly technical subject. The URL's section of this magazine contains many highly technical sources of such information.

Application Techniques

By Steve Litt
Gratuitously spreading liquid across your motherboard is a very poor idea. Perhaps the liquid is conductive at the ultra high frequencies of today's computers, or perhaps it will change the capacitance between foil traces. To the extent possible, lubricants should coat only mating metal portions of connectors.

My first attempt with WD40 was spraying it. What a mess -- I gave that up in a hurry. I thought of using an eyedropper, but even that would apply too much lubricant. I finally settled on the fingertip technique, which appeared to have worked perfectly, and I imagine would be useful for any cheap lubricant. Start by pouring a small quantity of the liquid into a small clear glass -- maybe a shotglass or a 10oz clear plastic glass. Then repeatedly dip your finger into the glass and rub the result onto connectors. Keep a paper towel around to dry your finger. Here are the methods I found to apply the liquid to various components:

Connection
 Application technique for inexpensive liquid lubricants
PS/2 mouse or keyboard
 Finger several drops into the connector connected to the mouse or keyboard cable. Roll the connector around so all its pins come into contact with the lubricant. Then insert/remove several times, and seat. Do not attempt to place any drops into the port connector on the back of the computer, but instead let the lubricant in the cable connector lubricate the port.
DIN keyboard
 Pour lubricant into the keyboard cable connector, and then discard some of it. With expensive lubricants, try to place a little bit on each pin. Then insert/remove several times, and seat. Do not attempt to place any drops into the port connector on the back of the computer, but instead let the lubricant in the cable connector lubricate the port.
Serial mouse
 Finger a drop or two onto the surface of the mouse cable connector, letting it soak into the holes. Then insert/remove several times, and seat. Do not attempt to place any drops into the port connector on the back of the computer, but instead let the lubricant in the cable connector lubricate the port.
IDE and floppy cables For each point on the cable that connects to a device or motherboard, finger a drop or two onto the surface of the mouse cable connector, letting it soak into the holes. Then insert/remove several times, and seat.
Daughtercard
 On each side of the daughtercard, finger a drop or two onto the card's connecting points. Finger several drops into the  PCI, AGP or ISA slot. Then insert/remove several times, and seat.
Memory modules
 On each side of the memory module, finger a drop onto the module's connecting points. Finger one to three drops into the memory module slot. Then VERY CAREFULLY insert/remove several times, and seat. Make sure it's seated fully, and that the retaining clips are correctly seated.

These techniques worked well with WD40 and Break-Free CLP, and I'd imagine they'd work well with most inexpensive liquid lubricants. Some of the "tuner spray" type lubricants spray too hard and too fine to capture in a shotglass. Perhaps those could be concentrated in the packaged red plastic "straw" at the bottom of a shotglass, maybe with plastic wrap covering the top of the shotglass. Once the material is in the shotglass, finger application can be accomplished.

For an expensive liquid such as Stabilant 22, follow the manufacturer's directions.

For a grease, I don't know. Female prong holes could be finger-stuffed with grease. Edges of daughtercards and memory modules could have finger applied grease, and maybe a tiny bead of grease along the bottom, with the hope that it gets shoved into the slot. But it seems to me that a liquid oil would be much easier to apply.
Steve Litt is the author of the Universal Troubleshooting Process courseware.   Steve can be reached atSteve Litt's email address.

The Right Lubricant

By Steve Litt
My research tells me that in safety critical applications like Xray machines and airplanes, Stabilant 22 is the way to go. It's made for such applications. Stabilant 22 is the one lubricant I've found so far specifically stating that it's designed for safety critical situations.

In non-critical applications such as my sole proprietorship, cost might be a factor. A 15 ml bottle of Stabilant 22 costs somewhere between $25.00 and $85.00, depending on whom you ask. 15 ml is roughly a half ounce -- one tablespoon. It's very little material.

In all fairness, everything I've read says that a tablespoon of Stabilant 22 goes a longggg way. Maybe a few years for a guy like me, who has a fleet of 5 or 6 computers. But of course, to get it to go a long way, you'd need to use it right, with no spillage or wastage. I understand the 15ml bottle comes with a tiny eyedropper to measure out the tiniest of quantities, so perhaps it's not difficult to get it to last. But I have a hard time envisioning treatment of an edge connector daughtercard with less than 6 normal sized drops of any lubricant.

Can you imagine if the company sold 4 ounce bottles for $49.95? Every single computer store, every single audio store, every company of any size, and all knowledgeable consumers would have it, because it would be obvious it would be a long term supply. I predict the company's revenue would increase because of hugely increased sales volume.

Stabilant appears to be the Cadillac of the industry, but there are alternatives. A similar product, called ProGold G100, costs a relatively cheap $25.95 for a 75ml spraycan. It's specifically designed for connector lubrication, and enjoys a great reputation on the Internet. I've used it -- it's good.

Lubricating contact cleaner (tuner spray) is probably an excellent alternative. It's made for electronic purposes, and it has a lubricant. This is probably your safest bet other than Stabilant. Rather than spraying it, spray it into a small clear glass and then finger it on. Unfortunately, it's under such high pressure that much of it is lost trying to get a few drops into a shotglass or jar. The best tuner spray type product I've found is called Lube Job. It's cheap, effective, enjoys a good reputation, and it's under less pressure than most other tuner sprays, so it's easier to capture in a glass.

If you want a slippery petroleum product, and you're willing to go with something not created for electronics, transmission fluid might do the trick. It's slick, very liquid, and contains detergent to clean junk out of the connector. At $1.49 per quart, it's trivially cheap. One of my friends has successfully used transmission fluid in electronic contact applications for years. However, subjectively it doesn't feel slippery enough. Place some between your fingers and rub, and you'll feel some gripping.

Break-Free CLP is slightly more expensive than transmission fluid, and once again not created specifically for electronics, Break-Free gun oil is a teflon-loaded oil made specifically for gun lubrication. Unlike transmission fluid, it feels slick between your fingers, no matter the pressure or rate of movement. In a connector application, it stays wet for at least several weeks (that's all the time I have into this experiment so far). The one problem with Break Free CLP is that it may harm plastics. I placed it in a cheap, clear, throwaway plastic glass, and after a couple days it ate a hole through that glass. Subsequent work with plastic pill bottles and other plastic environments failed to show any plastic damage, but that original cheap glass could be a matter of concern for some. As a side note, Break Free CLP is a spectacular all-around lubricant, and works wonders on sticky bicycle brakes and derailleurs.

Various greases might be a possibility if proper application techniques can be developed. However, to prevent fretting corrosion, a continuous lubrication layer must exist after insertion. A thick grease might be scraped off and not relocate into all spaces.

Your choice depends on a large degree on your willingness to take a risk. On safety critical or mission critical applications, I'd recommend Stabilant 22. For data bearing machines, I'd recommend Stabilant 22, ProGold G100, or else tuner spray. All three are made for electronics. Perhaps in the future you'll find out for sure that another lubricant does an excellent job on connectors, but you'll need to use it and watch the machine's performance for several years.

The place to experiment with other lubricants is on less important machines -- experimental machines and the like. That's where you'll use lubricants like transmission oil, gun oil, white grease, or dialectric grease.

That being said, I'm currently using Break-Free CLP on my entire fleet of computers, with excellent results so far.

The following is a list of lubricants I've tried or heard of, and my observations:

Lubricant
 Advantages
 Disadvantages
 Source
 Price
 Comment
Stabilant 22 Formulated for electronic contacts.
Special formula is an insulator on adjacent conductors, but as conductive as a solder joint for mating conductors.
Designed for safety critical applications.
The Cadillac of the industry.
 Fabulously expensive.
Tiny quantities make application challenging.
Difficult to find prices and distributors.
 http://www.stabilant.com/bccomp.htm
D.W. Chemicals or one of their distributors.
 15ml refill kit for $81.25.
 If failure is not an option, ignore the cost and use this product.
WD 40
 WD40 is always on hand.
Cheap.
Easy to apply.
 Waxy buildup likely.
 Most stores.
 Cheap -- varies.
 Don't use WD40 for electronic connectors except in dire emergencies.
Automatic Transmission Fluid (Dexron III)
 Dirt cheap.
Long track record.
Easy to apply.
 Not as slippery as one might like.
Not intended for electronic applications.
 Any auto store.
  $1.49 per quart.
 Try it on a non-critical computer, and see how it works for you.
Break Free CLP
 Very slippery.
Cheap.
Easy to apply.
Useful beyond electronics.
 Can destroy some plastics
 Wal Mart stores. <$4.00 per Right now, this is what I use the most for electronics work. Very slippery, easy to apply, cheap.
Contact/Control Cleaner & Lubricant
Radio Shack #64-4315
 Meant for electonic contacts.
Radio Shacks are everywhere.
 Mostly inert, pressurized ingredients cause freezing and widespread overspray, even shooting into a jar.
 Radio Shack Stores.
 About $8.00 per 4.5 oz spray can.
 More expensive and harder to apply than the Lube Job product.
ProGold G100
 Meant for electronic contacts.
Companion DeoxIT D100 available for extremely corroded contacts.

 Moderately expensive.
One shot push button hard to apply properly to connectors, and also hard to spray into a shotglass or jar.
 Caig Electronics.
http://caig.com
 $25.95 for a 75ml spraycan
 A high quality, more economical alternative to Stabilant 22.
Lube Job Electronics Lubricant
 Meant for electronic contacts.
Fairly cheap.
 Copious inert, pressurized ingredients cause freezing and widespread overspray, even shooting into a jar, although not as much so as the Radio Shack product. AVW inc.
http://www.
blowoff.com/lubejob/electlube.html.
 $7.95 per 11oz spraycan
 An excellent overall compromise that's designed for electronic contacts. This might be ideal for a computer store selling a lot of computers. Right now, this is the product I'd recommend to my friends.

I use Break-Free CLP for most of my electronic lubrication needs (and most of my bicycle needs too), but I advise you to use Lube Job Electronics Lubricant from AVW. It's probably the best tradeoff between safety, effectiveness, ease of use and price.

If you need more quality, step up to ProGold 100, or the Cadillac of the industry, Stabilant 22. Lube Job,  ProGold 100 and Stabilant 22 are made specifically for electronic contacts, and all are well respected in the industry. If the application is safety critical, I'd suggest taking a close look at Stabilant 22. I haven't used it, but its reputation on the Internet is pure gold.

If you need large quantities dirt cheap, try Dexron III Automatic Transmission Fluid. It's not made for electronic components, but it's been used for that in the past, and from what I hear worked well. You could condition every slot, SIMM and cable in 500 computers for $1.49 with a quart of transmission fluid.
Steve Litt is the author of Rapid Learning: Secret Weapon of the Successful Technologist . He can be reached atSteve Litt's email address.

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