Which contact cleaner do you use?

[helia]

(Not sure if this is the right board for this question but here it is..)

I'm new at this so I've had to buy a few things to help with the clean up of my 302 phone.  (Novus and Simichrome are great!) 

I've never bought an electrical contact cleaner before so I'm not sure what to buy.  I'm going to use it to clean up the terminal ends and the induction coil screws.  I'm deciding between the DeoxIT D5 and the DeoxIT D100 because the local store has them but I don't know if one is better or worse than the other.  Thoughts?  Any advice on buying something else?  Thanks for the help!

[LarryInMichigan]

I use a wire brush on a rotary tool to clean electrical contacts where possible.  It quickly removes dirt and oxidation.

Larry

[ESalter]

I hear carbon tetrachloride is a good contact cleaner, but I wouldn't recommend it  

My dad has some really good spray contact cleaner, I'll take a look at what it is tomorrow.

For phones I usually use a stainless wire brush as Larry said.  Another good took is a fiberglass brush.  Those aren't readily available at stores, but you can buy them online.  They work well to remove oxidation and other crust from plated surfaces without worrying about digging through the plating like stainless brushes sometimes can.

---Eric

[helia]

I live in a tiny NYC apartment so rotary tools are probably not the best idea - no idea where I would store it.   But I love the idea of the fiberglass brush! 

[poplar1]

"The contacts on 625A transmitters are silver plated and shall not be burnished. The tarnish that develops on these contacts is not detrimental."

Bell System Practices, Section C35.101, Issue 2, 2-10-37, page 2, paragraph 4.02

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It seems this would apply to any silver contacts. 

[A 625A transmitter is the one used on later E-type handsets. It contains the same F1 unit used in 302s.]


   

[New England Tel.]

For the tarnish that forms on handset contacts & elements, I just use a pencil eraser followed by a wipe with a soft cloth. Does great and removes no plating. For hookswitch & dial contacts, I use strips of old business cards - first, dry - then soaked with lighter fluid. Has always worked great for me.

[Russ Kirk]

"The contacts on 625A transmitters are silver plated and shall not be burnished. The tarnish that develops on these contacts is not detrimental."

Bell System Practices, Section C35.101, Issue 2, 2-10-37, page 2, paragraph 4.02

-------------------------------------------------------------------------------------------------
It seems this would apply to any silver contacts. 

[A 625A transmitter is the one used on later E-type handsets. It contains the same F1 unit used in 302s.]


   

When I was a PBX installer many years ago I faintly recall being given some WE small strips of a thick paper for burnishing contacts.  But, who knows, maybe my memory is failing....... Does anyone know if WE had paper strips for burnishing? 

[poplar1]

Yes, there were paper strips in manila envelopes supplied by WE. Do you recall which parts you used them on?

I don't know whether using paper strips or pencil erasers is considered burnishing or cleaning. I've heard that using an eraser on transmitter contacts is a good fix for static if swapping the unit doesn't help.

Still, I wonder if disassembling everything to wirebrush the screws or polish the gongs is necessary or even sometimes damaging. "If it ain't broke, don't fix it."

[Russ Kirk]

When I was a newbie with the phone company,  the had me spend some time time with an "old timer".   He had be cleaning contacts on a 701 PBX switch, TT dials and switchhooks, mostly call directors.   This place still had a few hardwired sets in place.  He was big believer in fixing the defective sets instead of just sending them back and grabbing a new one.   

A liitle off the subject , but.....
Ironically,  it was at the San Carlos, California GTE Lenkurt facility.

The telcom manager said it was cheaper to have Pacific Telephone do the work instead of having GTE employees brought in for installations and repairs.   

[poplar1]

When I was a newbie with the phone company,  the had me spend some time time with an "old timer".   He had be cleaning contacts on a 701 PBX switch, TT dials and switchhooks, mostly call directors.   This place still had a few hardwired sets in place.  He was big believer in fixing the defective sets instead of just sending them back and grabbing a new one.   

A liitle off the subject , but.....
Ironically,  it was at the San Carlos, California GTE Lenkurt facility.

The telcom manager said it was cheaper to have Pacific Telephone do the work instead of having GTE employees brought in for installations and repairs.   

A Call Director is one phone that is usually easier to fix than to replace, especially if there are previous modifications to the set. Otherwise, you have to figure out if additional buzzers were added, if the wiring has been changed because a pair in the station cable is bad, etc. Call Directors are one of the few post-1950 WE sets that have a network attached with a screw instead of rivets. (If the network was bad in a 500, for example, the set was considered not repairable in the field.) There was one early Call Director with a #6 dial at the Ga. D.O.T. building that no one wanted to change out because the lamp leads were grouped together like the 464 sets rather than the usual Tip, Ring, A, A1, Lamp Ground, Lamp for each line. Replacing the set would have required changing the connections at the IDF, and these were screw terminals, not 66 blocks.

We had one tech we nicknamed "Santa Clause" because he would always replace the phone on a trouble ticket. Customers always want a new phone---until the next day when they realize their trouble is still not cleared. Then he would say the trouble was outside.  After BellSouth charged us for a "No Trouble Found," another state tech would go clear the original trouble.

[southernphoneman]

if interested I tried the pencil eraser trick on the gongs on a ringer assembly and it works very well.

[ESalter]

All of these comments are right.  When I mentioned stainless and fiberglass brushes, I was picturing rusty or corroded screw terminals on networks.  Relay and hookswitch contacts are entirely different.  We have a contact burnishing tool I use on the strowger switches when they get dirty.  The burnishing sticks feel smooth and are dark gray like charcoal, but I believe they're made with diamond dust.  The problem with using card stock is fine paper pulp/dust will collect in the small cavities of the contact and cause it to be intermittent. 

---Eric

[helia]

I like things shiny and pretty but I think I'm going to leave well enough alone for now.  I'll try the eraser trick though!  Thanks for the help (and the stories)!

[Russ Kirk]

I few weeks ago I went to the store to replace my empty spray can of contact cleaner.  No such luck,  - could not find it.  So I looked online, Great Amazon has it. When I tried to place an order a mesage popped up and said they were not allowed to ship it to California.  Apparently, California has outlawed the sale of some forms of contact cleaner.  Arrrgghh!  Apparenly,  they think that banning in our state will protect the WHOLE planet!  I will have to go another route and get it another way.   So contact cleaning sprays may not be available in all states.  

As for the burnishing tools. Looking very quickly online I see they do make some that are safe for silver contacts.

http://pinballmagic.com/index.php?main_page=product_info&products_id=86

They say this one is  "Safe to to use on switches made of platinum, palladium, molybdenum, gold, tungsten and silver."  There are many other sellers of these same items.