Electrical Contact Material

F. Bertolazzi Inscribed thus:

Yes ! I've used pencil erasers to clean fingering on PCB contacts.

--
Best Regards:
                     Baron.

John Fields Inscribed thus:

Certain types of gaming machines use a stack of rotating disks of SRBP material, similar construction to a HDD platter stack, with phosphor bronze contact strips and sterling silver studs to determine payout values. The contact strips when not in contact with the studs are in continuous contact with the SRBP disk. Surprisingly over a long period of time grooves are formed in the SRBP disk surface. Since there is

240v 50Hz present on the contact studs, debris from the continual friction can cause arcing and breakdown of the SRBP material. The point being is that these things run reliably for years without maintenance.

--
Best Regards:
                     Baron.

Our field service staff had a sort of glass fiber propelling pencil for that. It was like a very thick propelling pencil, but instead of pencil lead, it had a dense mass of fine glass fibers, which wore down over time.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

ers'

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I DONT KNOW, GLASS FIBER MAY SCRATCH A SOFT METALIC SURFACE. RUBBER ON MAGNETIC HEADS IS GOOD BUT YOUD HAVE TO PPLISH THE SURFAC AGAIN.. FOR THE OP's PROBLEM A GOOD QUALITY SPRAY ELECTRONIC CLEANER WITH THE CIRCUIT DE-ENERGIZED AND MILD AIR BLASTS AFTER A GOOD THOROUGH FLUSH WILL SUFFICE.

YOU CAN DO MAGIC...YOU CAN DO ANYTHING THAT YOU DESIRE.

PATECUM

Even with gold there is still the issue of having to clean the contacts.

P.S.: I don't know if anyone else has this issue, but Google Groups will not let me post in another thread here that I started called. Making cables". I've attempting to post a response for the last three days. Has anyone else had a problem like this?

Thanks.

Darren Harris Staten Island, New York.

--
Unfortunately, most, if not all, (as I recall) paper tape was oiled in
order to increase the life of the punches, so wasn't really a good
contact-cleaning medium in the long run.

--
Maybe, maybe not.

If there's a wear issue, then the gold flash will just be wasted but
who knows?

The OP seems to be operating under "Loose Lips Sink Ships" so we may
never know what we helped him get to market.

--- Real life horror story:

Once upon a time, in a previous life, I used to design oceanographic instruments and farmed out the interface between a submersible Sound velocity/Temperature/Depth (STD) probe and the surface data acquisition system.

When we got the interface back it worked perfectly, and we took it to Japan and installed it on the ship doing the STD profiling of the Sea of Japan.

At first, everything was ducky, but then we started getting anomalous readings that made no sense.

Long story short, the PCB contact fingers were tin-lead, the backplane receptacles were gold, and the sea air did a number on the PCB contacts.

Solution, until the emergency ordered goldfingered PCB's arrived?

Unplug all of the interface's PCBs, rub down their contacts with an eraser, plug them back in, and start a run.

--- JF

--
Google groups, as far as USENET is concerned, is nothing more than a
web based SPAM outlet looking for revenue, and bites.

If you're really interested in verbal freedom and want to say what you
want to say without your network provider getting on your case, then
blow off google groups and get yourself a real USENET provider.

When I was an amusement machine repairmen, the company issued a thing that the boss called a "fiberglass eraser" for cleaning edge connector contacts.

It was just a bundle of stiff glass fibers in a plastic tube with a screw to extend the bundle of fibers as they wore down, and it worked a treat!

It didn't leave any rubber residue like a pencil eraser might have.

Cheers! Rich

To me, it sounds like a homework problem; I invented some contacts once; actually, I rescued them from a retired relay and just changed the mechanical configuration; this guy sounds like he's trying to reinvent the whole concept of relay contacts, or either he's a troll, twitting us all.

Isn't it frustrating when someone comes in and asks a question, and answer after answer, he says, "No, that's not it..."

After about three of those kind of responses, I just put them on my "ignore" list. Sometimes I say, "Well, what the hell _do_ you want to hear?"

Cheers! Rich

Rich Grise Inscribed thus:

Its very much "Horses for Courses" ! The Glass brush that you refer to are available right up to 2" diameter, and are very abrasive.

--
Best Regards:
                     Baron.

use

th

e

ay

YOU SHOULD DO A LITTLE MORE RESEARCH ON WHAT USENET REALLY IS TODAY. ...EVERYONE THAT SPONSORED IT GAVE UP ON IT A WHILE BACK..EXCEPT GOOGLE... WHAT YOU HAVE IS A MIRROR READER FROM A PRIVATE ISP SUBSCRIPTION... MY TAKE IS THE BOYS N GIRLS AT GOOGLE ARE JUST FOLLOWING BY EXAMPLE.. BUT ADJUSTING AND MODIFYING EVERY MOVE WITH THE NEW EXPERIENCES.

BUT WHAT DO I KNOW..I AM JUST A GHOST MINDING THIS FABULOUS MEDIUM :)

PATECUM

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h y e r

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I DONT KNOW WHATS WORSE, WHAT YOU SAID, OR THE OPs GETTING A GOOD RESPONSE BUT CLAMMING UP ABOUT IT, I CAN SENSE THE VICTORY GRIN ON HIS N HER FACE......IT's ALL IN A DAYS WORK. PAT ECUM

Andrew Gabriel:

Yes, it's an eraser for china ink used by achitects on tracing paper. Very effective. Maybe too much.

John Fields:

Now I understand why you had to deal with drydocks. Usually those places are populated with retarded monkeys, you did not seem to fit wery well there (apart from the fact that you're an asshole. Now we're even, peace).

I've been on board one of those "oceanographic" vessels. Their base in the west Mediterranean is in La Spezia, 100 km from here.

Yeah, sure, nothing to deal with russian submarines. ;-)

A couple of weeks ago I "repaired" a friend's "boom box" the same way.

Rich Grise:

Nor metal residues where there were the contacts. :D

It's the same thing A. Gabriel was talking about.

I still have two of those, to be used in really difficult situations.

. e

TEEHEEHEE ... REFER HIM TO BILLINGS BERT......THAT''LL EVEN THINGS UP EVEN BETTER. LOL ... NOT REALLY BUT ... BWUAHAHAHAHA.... RIGHT ON ! PAT ECUM

Nah. We routinely used them on gold edge fingers, and I never saw one take off any observable amount of gold.

But you don't use it like a grinder!

Thanks, Rich