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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Cleaning Plated Electrical Contacts?
Have been Googling the proper way to clean plated electrical contacts
but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene |
#2
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Cleaning Plated Electrical Contacts?
GeneO wrote in message
... Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene Assuming not sputter damaged contacts, otherwise good underlying surfaces. I use a nylon cable tie, introduced with the contacts in contact. In a filing action with the ratchet part of the nylon, then turn upside down and repeat -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#3
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Cleaning Plated Electrical Contacts?
In article
, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. A good contact cleaner followed by a switch lubricant - will help prevent corrosion later. Servisol or Electrolube for the latter. If a connector is too damaged would also be interested in what are considered the best type replacement. -- *The modem is the message * Dave Plowman London SW To e-mail, change noise into sound. |
#4
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Cleaning Plated Electrical Contacts?
On Sep 18, 8:28*am, GeneO wrote:
Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I get the impression that you are talking about pin and socket connectors rather than 'button' contacts as used in relays for example. First of all, connectors have a very finite numbers of mate-unmate cycles in their original design and once they reach that number [either half] they are basically scrap. Further, if you mate a worn out connector with a good one, you may contaminate the surface of the 'good' half and compromise it's future performance. Except for connectors especially designed for large numbers of mating, most commercial connectors are good for 50 to 200 cycles, and that is highly dependent on the environmental conditions [dust and grit are a quick death]. Once the surface plating is worn through or the pins have overheated and lost some spring tension, there is nothing one can do to improve the connection but replace it with NEW components. Best replacement? Depends on the application. A lot of engineering goes into the choice of a simple connector for a product if long life and durability are needed. Neil S. |
#5
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Cleaning Plated Electrical Contacts?
In article , nesesu wrote:
On Sep 18, 8:28=A0am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I get the impression that you are talking about pin and socket connectors rather than 'button' contacts as used in relays for example. First of all, connectors have a very finite numbers of mate-unmate cycles in their original design and once they reach that number [either half] they are basically scrap. Further, if you mate a worn out connector with a good one, you may contaminate the surface of the 'good' half and compromise it's future performance. Except for connectors especially designed for large numbers of mating, most commercial connectors are good for 50 to 200 cycles, and that is highly dependent on the environmental conditions [dust and grit are a quick death]. Once the surface plating is worn through or the pins have overheated and lost some spring tension, there is nothing one can do to improve the connection but replace it with NEW components. Best replacement? Depends on the application. A lot of engineering goes into the choice of a simple connector for a product if long life and durability are needed. Neil S. The OP didn't say a whole lot. Some oxides can be removed with water, like the green type. Not many contact cleaners actually remove oxide. Oleic acid based cleaners will help remove oxides as well as friction. greg |
#6
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Cleaning Plated Electrical Contacts?
The original Caig Cramolin (red) works well on tin and nickel surfaces.
ProGold does a fairly good job on gold surfaces. Go to the Caig site and see what you think. Try not to be too alarmed at the high prices. (These are "professional" (not consumer) products, and Caig gouges.) There are probably other effective products out there. |
#7
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Cleaning Plated Electrical Contacts?
"nesesu" wrote in message ... On Sep 18, 8:28 am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I get the impression that you are talking about pin and socket connectors rather than 'button' contacts as used in relays for example. First of all, connectors have a very finite numbers of mate-unmate cycles in their original design and once they reach that number [either half] they are basically scrap. Further, if you mate a worn out connector with a good one, you may contaminate the surface of the 'good' half and compromise it's future performance. Except for connectors especially designed for large numbers of mating, most commercial connectors are good for 50 to 200 cycles, and that is highly dependent on the environmental conditions [dust and grit are a quick death]. Neil S. That seems a bit pessimistic. I have many lead sets in my workshop - phono, jack, XLR, Speakon, SCART etc - which have been made up using fairly 'bog-standard' connectors from the likes of Maplin, Farnell etc, or bought ready made from the same sources, and these are used several times, just about every day, to connect up items that are in for repair. Many have been in use for years. Musical instruments are jacked into amplifiers and mixer desks many many more times than 200 in their life, and most such items employ very 'standard' and inexpensive makes and designs of jacks and plugs. I think that I would be pretty disappointed with *any* connector in a user application, no matter how cheap and nasty it was, that was considered shagged out after as little as 200 uses. Arfa |
#8
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Cleaning Plated Electrical Contacts?
First of all, connectors have a very finite numbers of mate-unmate
cycles in their original design and once they reach that number [either half] they are basically scrap. Further, if you mate a worn out connector with a good one, you may contaminate the surface of the 'good' half and compromise its future performance. Except for connectors especially designed for large numbers of mating, most commercial connectors are good for 50 to 200 cycles, and that is highly dependent on the environmental conditions [dust and grit are a quick death]. That's an awfully small number. A properly manufactured gold-plated connector should be good for at least 10 times that, shouldn't it? I'm pretty certain the sorts of connectors used on (say) flash RAM are good for a couple thousand cycles. They'd have to be (???), as it's assumed the card will be repeatedly inserted and removed. |
#9
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Cleaning Plated Electrical Contacts?
GeneO wrote:
Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. For brass 316 jack plugs, use a green nylon scouring pad. If the corrosion is on battery connectors that have been used with alkaline batteries, you will wreck the surface with dry physical cleaning before you make contact - but with a drop of water, the corrosion comes off easily. -- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk |
#10
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Cleaning Plated Electrical Contacts?
On Sep 18, 9:46*am, "William Sommerwerck"
wrote: First of all, connectors have a very finite numbers of mate-unmate cycles in their original design... most commercial connectors are good for 50 to 200 cycles That's an awfully small number. A properly manufactured gold-plated connector should be good for at least 10 times that, shouldn't it? If you have logic levels in mind, and some noise margin, a slightly dirty connector is no big issue. Some RF test equipment, though, has to be concerned with milliohms of resistance, and can be completely defeated by a small amount of oxide (like, a copper oxide rectifier making harmonics out of your main signal, or a mechanical vibration sensitivity - the avionics guys hate that). So, commercial connectors that are 'good' for 200 cycles are possibly adequate for 10,000. There's a few critical applications where connector insertions are counted and connector-replace is performed at suitable intervals. |
#11
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Cleaning Plated Electrical Contacts?
On Fri, 18 Sep 2009 08:28:42 -0700 (PDT), GeneO wrote:
:Have been Googling the proper way to clean plated electrical contacts :but either get nothing if use " or a lot of nonrelevant hits without. : :Am interested in any suggestions esp how to remove the nonconductive xides. : :If a connector is too damaged would also be interested in what are :considered the best type replacement. : :Thanks : :Gene I don't think I have ever come across a "plated" electrical contact. In my experience electrical contacts are always a solid material such as brass (cheap and nasty - often used in electrical appliances) or a more exotic alloy material such as nickel-silver. The contact material used is dependant on the application (AC or DC and whether inductive) and the magnitude of the current being handled. Most relay contacts can be cleaned and reconditioned using a contact burnishing tool such as http://www.mcmelectronics.com/product/22-910 The use of a lubricant such as those mentioned in other responses may be considered useful. |
#12
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Cleaning Plated Electrical Contacts?
"Ross Herbert" wrote in message ... On Fri, 18 Sep 2009 08:28:42 -0700 (PDT), GeneO wrote: :Have been Googling the proper way to clean plated electrical contacts :but either get nothing if use " or a lot of nonrelevant hits without. : :Am interested in any suggestions esp how to remove the nonconductive xides. : :If a connector is too damaged would also be interested in what are :considered the best type replacement. : :Thanks : :Gene I don't think I have ever come across a "plated" electrical contact. In my experience electrical contacts are always a solid material such as brass (cheap and nasty - often used in electrical appliances) or a more exotic alloy material such as nickel-silver. The contact material used is dependant on the application (AC or DC and whether inductive) and the magnitude of the current being handled. I'm sure that you must have, Ross ?? I'd agree with you on 'solid brass contacts' in clunky mains power switches etc, but elsewhere, many contacts seem to be plated rather than solid. For instance, I just put the word "plated" into the search pane on one component supplier's website, and it came back with 59 items, most of which were connectors with a variety of plating materials quoted for their contacts, including gold, silver & tin. Similarly, a quick look in a catalogue at switches, reveals many to have either gold or silver plated contacts. Also, many relays have contacts described variously as gold "plated", "covered", "overlayed" etc. It is these contacts that I find you have to be careful not to use any kind of abrasion on, for fear of going through the very thin layer of plating. I generally find that pulling a piece of dry cardboard through things like relay contacts, is enough to clean them. A tiny spot of cleaner/lubricant introduced to the contact gap, finishes the job off. Arfa |
#13
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Cleaning Plated Electrical Contacts?
On Sep 18, 10:28*am, GeneO wrote:
Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I have had very good luck repairing low current relay contacts and mechanical rotary switches using "tarn-x" silver cleaner containing acidified thiourea. MSDS: http://www.jelmar.com/msds/TX_MSDS_eng.pdf. If you take the relay or switch apart to get to the contacts, use a cotton swab with a small amount of cleaner and apply to the oxidized (tarnished) surfaces. They shine right up and the surface does not appear to be damaged by it. Then dry and apply a very light film of silicone based contact cleaner to keep the air away and help with lubrication. Works great for speaker relays in amplifiers and mode switches for VCR's. Scott |
#14
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Cleaning Plated Electrical Contacts?
In article , Dubtron wrote:
On Sep 18, 10:28=A0am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I have had very good luck repairing low current relay contacts and mechanical rotary switches using "tarn-x" silver cleaner containing acidified thiourea. MSDS: http://www.jelmar.com/msds/TX_MSDS_eng.pdf. If you take the relay or switch apart to get to the contacts, use a cotton swab with a small amount of cleaner and apply to the oxidized (tarnished) surfaces. They shine right up and the surface does not appear to be damaged by it. Then dry and apply a very light film of silicone based contact cleaner to keep the air away and help with lubrication. Works great for speaker relays in amplifiers and mode switches for VCR's. Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg |
#15
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Cleaning Plated Electrical Contacts?
GregS wrote: In article , Dubtron wrote: On Sep 18, 10:28=A0am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I have had very good luck repairing low current relay contacts and mechanical rotary switches using "tarn-x" silver cleaner containing acidified thiourea. MSDS: http://www.jelmar.com/msds/TX_MSDS_eng.pdf. If you take the relay or switch apart to get to the contacts, use a cotton swab with a small amount of cleaner and apply to the oxidized (tarnished) surfaces. They shine right up and the surface does not appear to be damaged by it. Then dry and apply a very light film of silicone based contact cleaner to keep the air away and help with lubrication. Works great for speaker relays in amplifiers and mode switches for VCR's. Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. Silicone based chemicals were banned from all telephone switching centers with mechanical switching. The old General Cement "Tuner Lube" is petroleum based and doesn't build up an insulating film like Silicone based products. -- You can't have a sense of humor, if you have no sense! |
#16
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Cleaning Plated Electrical Contacts?
Silicone based products are really not a good thing, at least thats what
some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg Silicone based cleaners leave a residue that protects against friction but tends to insulate. You have to break through the film in order to even have contact. I have found them useful for connectors that see lots of use, such as Notebooks, but I usually have to wash them with Isopropyl to remove most of what I put on. There is no point in lubing relays. Any residue will increase the likelihood of burning of the contacts. They should be cleaned and burnished with a non-residue cleaner and as minimally abrasive tool as possible. Bond paper strips will often suffice. Isopropyl Alcohol at 90% or better is clean, leaves no residue, won't harm most plastics and is the only recommended cleaner for many switches and contacts. Do not use less than 90% as there will be risk of moisture damage. |
#17
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Cleaning Plated Electrical Contacts?
In article , "Michael A. Terrell" wrote:
GregS wrote: In article , Dubtron wrote: On Sep 18, 10:28=A0am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I have had very good luck repairing low current relay contacts and mechanical rotary switches using "tarn-x" silver cleaner containing acidified thiourea. MSDS: http://www.jelmar.com/msds/TX_MSDS_eng.pdf. If you take the relay or switch apart to get to the contacts, use a cotton swab with a small amount of cleaner and apply to the oxidized (tarnished) surfaces. They shine right up and the surface does not appear to be damaged by it. Then dry and apply a very light film of silicone based contact cleaner to keep the air away and help with lubrication. Works great for speaker relays in amplifiers and mode switches for VCR's. Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. Silicone based chemicals were banned from all telephone switching centers with mechanical switching. The old General Cement "Tuner Lube" is petroleum based and doesn't build up an insulating film like Silicone based products. I got some of that stuff. For rubber and some plastics petroleum based products can hurt. I have been using plastic safe liquid CRC 2-26 but I really don't know whats in it. For those outside the US, if you use Cramolin Contaclean, it must be removed after cleaning because it will gum. Here is an old can. Check out the buildup at the top. http://zekfrivolous.com/misc/cramolin%20contaclean.JPG greg |
#18
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Cleaning Plated Electrical Contacts?
In article , "JB" wrote:
Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg Silicone based cleaners leave a residue that protects against friction but tends to insulate. You have to break through the film in order to even have contact. I have found them useful for connectors that see lots of use, such as Notebooks, but I usually have to wash them with Isopropyl to remove most of what I put on. There is no point in lubing relays. Any residue will increase the likelihood of burning of the contacts. They should be cleaned and burnished with a non-residue cleaner and as minimally abrasive tool as possible. Bond paper strips will often suffice. Isopropyl Alcohol at 90% or better is clean, leaves no residue, won't harm most plastics and is the only recommended cleaner for many switches and contacts. Do not use less than 90% as there will be risk of moisture damage. I kind of like using 70% rubbing alcohol sometimes, with its small amount of mineral oil. Any % alcohol can cause moisture problems, even 100%. The trick is to warm dry it. My knowledge of silicon is it forms waterglass in some cases and insulates. This is a powder like material. Sodium silicate. It does wash off. I also discovered thick sticky residue on my can of CRC 2-26, but its a more passive lube than the acedic nature of Cramolin Contaclean. My can of TAL-5 is also sticky, was made by WD-40 company. From memory I have never seen this happen with WD-40. greg |
#19
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Cleaning Plated Electrical Contacts?
In article ,
Ross Herbert wrote: I don't think I have ever come across a "plated" electrical contact. In my experience electrical contacts are always a solid material such as brass (cheap and nasty - often used in electrical appliances) or a more exotic alloy material such as nickel-silver. The vast majority of connectors which aren't plain brass are plated. -- *When cheese gets it's picture taken, what does it say? Dave Plowman London SW To e-mail, change noise into sound. |
#21
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Cleaning Plated Electrical Contacts?
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#22
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Cleaning Plated Electrical Contacts?
Jim Yanik wrote: (GregS) wrote in : In article , "JB" wrote: Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg Silicone based cleaners leave a residue that protects against friction but tends to insulate. You have to break through the film in order to even have contact. I have found them useful for connectors that see lots of use, such as Notebooks, but I usually have to wash them with Isopropyl to remove most of what I put on. There is no point in lubing relays. Any residue will increase the likelihood of burning of the contacts. They should be cleaned and burnished with a non-residue cleaner and as minimally abrasive tool as possible. Bond paper strips will often suffice. Isopropyl Alcohol at 90% or better is clean, leaves no residue, won't harm most plastics and is the only recommended cleaner for many switches and contacts. Do not use less than 90% as there will be risk of moisture damage. I kind of like using 70% rubbing alcohol sometimes, with its small amount of mineral oil. Any % alcohol can cause moisture problems, even 100%. The trick is to warm dry it. Rubbing alcohol shouldn't have any mineral oil in it. I prefer 90% isopropyl.It also absorbs any water or moisture. Some has 'Oil of Wintergreen' but that is usually colored green. It is an old type of pain killer. They still make it, but they don't use real 'Oil of Wintergreen'. between the dye and other additives, I wouldn't use it on electronics. I do use it for some types of pain in my hands, from the Diabetic Neuropathy. -- You can't have a sense of humor, if you have no sense! |
#23
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Cleaning Plated Electrical Contacts?
In article , Jim Yanik wrote:
(GregS) wrote in : In article , "Michael A. Terrell" wrote: GregS wrote: In article , Dubtron wrote: On Sep 18, 10:28=A0am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I have had very good luck repairing low current relay contacts and mechanical rotary switches using "tarn-x" silver cleaner containing acidified thiourea. MSDS: http://www.jelmar.com/msds/TX_MSDS_eng.pdf. If you take the relay or switch apart to get to the contacts, use a cotton swab with a small amount of cleaner and apply to the oxidized (tarnished) surfaces. They shine right up and the surface does not appear to be damaged by it. Then dry and apply a very light film of silicone based contact cleaner to keep the air away and help with lubrication. Works great for speaker relays in amplifiers and mode switches for VCR's. Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. Silicone based chemicals were banned from all telephone switching centers with mechanical switching. The old General Cement "Tuner Lube" is petroleum based and doesn't build up an insulating film like Silicone based products. contact wiping pressure should handle that "insulating" film. Only TEK "HF switch contacts" didn't have enough wiping pressure to deal with films left from tuner cleaner/lube sprays. I got some of that stuff. For rubber and some plastics petroleum based products can hurt. I have been using plastic safe liquid CRC 2-26 but I really don't know whats in it. For those outside the US, if you use Cramolin Contaclean, it must be removed after cleaning because it will gum. Here is an old can. Check out the buildup at the top. http://zekfrivolous.com/misc/cramolin%20contaclean.JPG greg I used to use Tarn-X on TEK 500 series tube scope rotary switches,to clean off the black oxidation. It worked great,had to wash and oven-dry the scopes anyways. You must RINSE the contacts after using Tarn-X on them. Been there. I love big silver plated ceramic switches. A friend used to say, he liked using both Cramolin Red and Tweek on contacts, together. The current Caig R100 full strength is also great. greg |
#24
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Cleaning Plated Electrical Contacts?
In article , Jim Yanik wrote:
(GregS) wrote in : In article , "JB" wrote: Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg Silicone based cleaners leave a residue that protects against friction but tends to insulate. You have to break through the film in order to even have contact. I have found them useful for connectors that see lots of use, such as Notebooks, but I usually have to wash them with Isopropyl to remove most of what I put on. There is no point in lubing relays. Any residue will increase the likelihood of burning of the contacts. They should be cleaned and burnished with a non-residue cleaner and as minimally abrasive tool as possible. Bond paper strips will often suffice. Isopropyl Alcohol at 90% or better is clean, leaves no residue, won't harm most plastics and is the only recommended cleaner for many switches and contacts. Do not use less than 90% as there will be risk of moisture damage. I kind of like using 70% rubbing alcohol sometimes, with its small amount of mineral oil. Any % alcohol can cause moisture problems, even 100%. The trick is to warm dry it. Rubbing alcohol shouldn't have any mineral oil in it. I prefer 90% isopropyl.It also absorbs any water or moisture. The reason there is oil in some, its supposed to give oil back to the skin after a rub down. After using alcohol on the skin its usually very patchy looking removing the oils. I didn't exactly point out, even using 100% alcohol on things, and you will get water build up, after the alcohol starts absorbing it, and dries, leaving water. Plus, 100% is contaminated with drying agents. greg |
#25
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Cleaning Plated Electrical Contacts?
In article , "Michael A. Terrell" wrote:
Jim Yanik wrote: (GregS) wrote in : In article , "JB" wrote: Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg Silicone based cleaners leave a residue that protects against friction but tends to insulate. You have to break through the film in order to even have contact. I have found them useful for connectors that see lots of use, such as Notebooks, but I usually have to wash them with Isopropyl to remove most of what I put on. There is no point in lubing relays. Any residue will increase the likelihood of burning of the contacts. They should be cleaned and burnished with a non-residue cleaner and as minimally abrasive tool as possible. Bond paper strips will often suffice. Isopropyl Alcohol at 90% or better is clean, leaves no residue, won't harm most plastics and is the only recommended cleaner for many switches and contacts. Do not use less than 90% as there will be risk of moisture damage. I kind of like using 70% rubbing alcohol sometimes, with its small amount of mineral oil. Any % alcohol can cause moisture problems, even 100%. The trick is to warm dry it. Rubbing alcohol shouldn't have any mineral oil in it. I prefer 90% isopropyl.It also absorbs any water or moisture. Some has 'Oil of Wintergreen' but that is usually colored green. It is an old type of pain killer. They still make it, but they don't use real 'Oil of Wintergreen'. between the dye and other additives, I wouldn't use it on electronics. I do use it for some types of pain in my hands, from the Diabetic Neuropathy. You will get dry patches of blue. I got an experiance I never felt. I eat hot peppers all the time, and have heard of capsation rub for pain. Capsation particles are extremely small and float in the air. Well, I was cleaning some Habenero and jalapeño peppers in haste scraping the seeds out and taking most of the core. Besides having to wash hands many times and being carefull, after about 20 minuites I started to feel the action penetrating the skin on my hands. They were tingly, much the same as a burn would do but mild. It wasn't a real bad feeling, but I could see how it might numb pain in the joints. Also try vitamin D. If your out in the sun, forget it. Just take minerals. 1000-2000 units D-3. greg |
#26
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Cleaning Plated Electrical Contacts?
"GregS" wrote in message ... In article , Dubtron wrote: On Sep 18, 10:28=A0am, GeneO wrote: Have been Googling the proper way to clean plated electrical contacts but either get nothing if use " or a lot of nonrelevant hits without. Am interested in any suggestions esp how to remove the nonconductive oxides. If a connector is too damaged would also be interested in what are considered the best type replacement. Thanks Gene I have had very good luck repairing low current relay contacts and mechanical rotary switches using "tarn-x" silver cleaner containing acidified thiourea. MSDS: http://www.jelmar.com/msds/TX_MSDS_eng.pdf. If you take the relay or switch apart to get to the contacts, use a cotton swab with a small amount of cleaner and apply to the oxidized (tarnished) surfaces. They shine right up and the surface does not appear to be damaged by it. Then dry and apply a very light film of silicone based contact cleaner to keep the air away and help with lubrication. Works great for speaker relays in amplifiers and mode switches for VCR's. Silicone based products are really not a good thing, at least thats what some say. However sometimes a silicone grease is used to protect connections. Silicone sprays were common 30 years ago. I don't recall any of the more common recommended sprays having silicone. I see mixed recommendations of lubing relays. Some say no, but I do. greg Years ago, we used to treat the long multipole open slide switches that were fitted to dual standard TV sets, to a liberal does of white heatsink paste. This did a grand job of stopping the sections that did the timebase switching, from arcing, and the sections that did the low-level signal switching, from tarnishing and becoming intermittent. Happy days. Gentler times ... Arfa |
#27
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Cleaning Plated Electrical Contacts?
On Mon, 21 Sep 2009 09:41:18 +0100, "Arfa Daily"
wrote: : :"Ross Herbert" wrote in message .. . : On Fri, 18 Sep 2009 08:28:42 -0700 (PDT), GeneO wrote: : : :Have been Googling the proper way to clean plated electrical contacts : :but either get nothing if use " or a lot of nonrelevant hits without. : : : :Am interested in any suggestions esp how to remove the nonconductive : xides. : : : :If a connector is too damaged would also be interested in what are : :considered the best type replacement. : : : :Thanks : : : :Gene : : : I don't think I have ever come across a "plated" electrical contact. In my : experience electrical contacts are always a solid material such as brass : (cheap : and nasty - often used in electrical appliances) or a more exotic alloy : material : such as nickel-silver. The contact material used is dependant on the : application : (AC or DC and whether inductive) and the magnitude of the current being : handled. : : :I'm sure that you must have, Ross ?? I'd agree with you on 'solid brass :contacts' in clunky mains power switches etc, but elsewhere, many contacts :seem to be plated rather than solid. For instance, I just put the word :"plated" into the search pane on one component supplier's website, and it :came back with 59 items, most of which were connectors with a variety of lating materials quoted for their contacts, including gold, silver & tin. :Similarly, a quick look in a catalogue at switches, reveals many to have :either gold or silver plated contacts. Also, many relays have contacts :described variously as gold "plated", "covered", "overlayed" etc. It is :these contacts that I find you have to be careful not to use any kind of :abrasion on, for fear of going through the very thin layer of plating. I :generally find that pulling a piece of dry cardboard through things like :relay contacts, is enough to clean them. A tiny spot of cleaner/lubricant :introduced to the contact gap, finishes the job off. : :Arfa : My experience has been mainly related to relays of both open and enclosed types, from miniature pcb mounted types for signal transmission to heavy duty high current capacity types. I will agree that particularly for the low level signal types the manufacturers often "enhance" the contact material by adding a gold "overlay". However, the actual relay contact will be made of some alloy material such as silver-palladium or other mixture. The contact is usually rivetted or welded to the spring leaf, which is probably a plated phosphor bronze material, while the gold overlay on the contact pips is simply to reduce contact resistance due to oxidation through lack of a wetting current. A typical relay of this type, which I have on hand, is the Fujitsu FBR46. With such relays, as you have mentioned, you never use abrasive methods of cleaning or burnishing but with gold as an overlay this should not be necessary. The problem with any "plated" contact is that once the plating material has been lost either through repeated operation or arcing etc, the base contact material is all that is left. In cases where no plating is used unless the contact material is one of the recognised traditional materials such as nickel-silver, silver-palladium etc, the electrical performance of the contact will be unreliable. Such a relay used for heavy current carrying capacity which I also have on hand is a Fuji HH62 witha contact rating at 10A. In this case the contact material is simply a "silver alloy" - probably made to Fuji specification. Such contacts can be burnished and reconditioned using abrasive tools. It may be that later contacts, manufactured for cheapness, do not use traditional solid alloy contact material which is rivetted or welded to the base contact spring material, and by so doing they would, in my opinion, be inferior to the types which do. |
#28
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Cleaning Plated Electrical Contacts?
Arfa Daily wrote:
That seems a bit pessimistic[...] Your blockquoting looks pretty sad. http://groups.google.com/group/sci.e...6?dmode=source Have you heard of this 3rd-party update for your M$ software? http://google.com/search?q=inurl:jain+%22+OE.doesn't.exactly.feature .the.most.intelligent.quoting.algorithm |
#29
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Cleaning Plated Electrical Contacts?
"JeffM" wrote in message ... Arfa Daily wrote: That seems a bit pessimistic[...] Your blockquoting looks pretty sad. http://groups.google.com/group/sci.e...6?dmode=source Have you heard of this 3rd-party update for your M$ software? http://google.com/search?q=inurl:jain+%22+OE.doesn't.exactly.feature .the.most.intelligent.quoting.algorithm Funnily enough, as soon as I replied to that particular post, I thought it looked 'wrong' ... To be fair, I don't usually quote in a way that appears "sad" or confused as far as I am aware. When my replies pop up in threads, they usually seem to look ok on my machine. However, thanks for the pointer to that piece of software. I've put it on now, so perhaps that will allow my posts to present in a way that does not further upset your sensibilities ... I'm sure you'll let me know if that's not the case ?? :-) Arfa |
#30
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Cleaning Plated Electrical Contacts?
"Ross Herbert" wrote in message ... On Mon, 21 Sep 2009 09:41:18 +0100, "Arfa Daily" wrote: : :"Ross Herbert" wrote in message .. . : On Fri, 18 Sep 2009 08:28:42 -0700 (PDT), GeneO wrote: : : :Have been Googling the proper way to clean plated electrical contacts : :but either get nothing if use " or a lot of nonrelevant hits without. : : : :Am interested in any suggestions esp how to remove the nonconductive : xides. : : : :If a connector is too damaged would also be interested in what are : :considered the best type replacement. : : : :Thanks : : : :Gene : : : I don't think I have ever come across a "plated" electrical contact. In my : experience electrical contacts are always a solid material such as brass : (cheap : and nasty - often used in electrical appliances) or a more exotic alloy : material : such as nickel-silver. The contact material used is dependant on the : application : (AC or DC and whether inductive) and the magnitude of the current being : handled. : : :I'm sure that you must have, Ross ?? I'd agree with you on 'solid brass :contacts' in clunky mains power switches etc, but elsewhere, many contacts :seem to be plated rather than solid. For instance, I just put the word :"plated" into the search pane on one component supplier's website, and it :came back with 59 items, most of which were connectors with a variety of lating materials quoted for their contacts, including gold, silver & tin. :Similarly, a quick look in a catalogue at switches, reveals many to have :either gold or silver plated contacts. Also, many relays have contacts :described variously as gold "plated", "covered", "overlayed" etc. It is :these contacts that I find you have to be careful not to use any kind of :abrasion on, for fear of going through the very thin layer of plating. I :generally find that pulling a piece of dry cardboard through things like :relay contacts, is enough to clean them. A tiny spot of cleaner/lubricant :introduced to the contact gap, finishes the job off. : :Arfa : My experience has been mainly related to relays of both open and enclosed types, from miniature pcb mounted types for signal transmission to heavy duty high current capacity types. I will agree that particularly for the low level signal types the manufacturers often "enhance" the contact material by adding a gold "overlay". However, the actual relay contact will be made of some alloy material such as silver-palladium or other mixture. The contact is usually rivetted or welded to the spring leaf, which is probably a plated phosphor bronze material, while the gold overlay on the contact pips is simply to reduce contact resistance due to oxidation through lack of a wetting current. A typical relay of this type, which I have on hand, is the Fujitsu FBR46. With such relays, as you have mentioned, you never use abrasive methods of cleaning or burnishing but with gold as an overlay this should not be necessary. The problem with any "plated" contact is that once the plating material has been lost either through repeated operation or arcing etc, the base contact material is all that is left. In cases where no plating is used unless the contact material is one of the recognised traditional materials such as nickel-silver, silver-palladium etc, the electrical performance of the contact will be unreliable. Such a relay used for heavy current carrying capacity which I also have on hand is a Fuji HH62 witha contact rating at 10A. In this case the contact material is simply a "silver alloy" - probably made to Fuji specification. Such contacts can be burnished and reconditioned using abrasive tools. It may be that later contacts, manufactured for cheapness, do not use traditional solid alloy contact material which is rivetted or welded to the base contact spring material, and by so doing they would, in my opinion, be inferior to the types which do. OK. Understand what you're saying ... Arfa |
#31
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Cleaning Plated Electrical Contacts?
Arfa Daily wrote:
"JeffM" wrote in message ... Arfa Daily wrote: That seems a bit pessimistic[...] Your blockquoting looks pretty sad. http://groups.google.com/group/sci.e...6?dmode=source Have you heard of this 3rd-party update for your M$ software? http://google.com/search?q=inurl:jain+%22+OE.doesn't.exactly.feature .the.most.intelligent.quoting.algorithm Funnily enough, as soon as I replied to that particular post, I thought it looked 'wrong' ... To be fair, I don't usually quote in a way that appears "sad" or confused as far as I am aware. When my replies pop up in threads, they usually seem to look ok on my machine. However, thanks for the pointer to that piece of software. I've put it on now, so perhaps that will allow my posts to present in a way that does not further upset your sensibilities ... I'm sure you'll let me know if that's not the case ?? :-) Arfa This looks much better. Often text you cited from previous posts appeared inline as if it were your original material Michael |
#32
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Cleaning Plated Electrical Contacts?
"msg" wrote in message ernet... Arfa Daily wrote: "JeffM" wrote in message ... Arfa Daily wrote: That seems a bit pessimistic[...] Your blockquoting looks pretty sad. http://groups.google.com/group/sci.e...6?dmode=source Have you heard of this 3rd-party update for your M$ software? http://google.com/search?q=inurl:jain+%22+OE.doesn't.exactly.feature .the.most.intelligent.quoting.algorithm Funnily enough, as soon as I replied to that particular post, I thought it looked 'wrong' ... To be fair, I don't usually quote in a way that appears "sad" or confused as far as I am aware. When my replies pop up in threads, they usually seem to look ok on my machine. However, thanks for the pointer to that piece of software. I've put it on now, so perhaps that will allow my posts to present in a way that does not further upset your sensibilities ... I'm sure you'll let me know if that's not the case ?? :-) Arfa This looks much better. Often text you cited from previous posts appeared inline as if it were your original material Michael Interesting that you say "often". I really hadn't noticed that this occured except on the odd occasion, and I had always put that down to there being something amiss in the formatting of the text that I was 'breaking into' with my comments. I don't very often reply in that way, answering individual points within the text body of the original post. Normally, I append a total reply to the bottom of the post, sometimes snipping irrelevant text from above or below, if it is one specific point that I am replying to, or where the post has become unnecessarily rambling. I had always thought that the original text gained right arrows at the start of each line automatically, with my text identified by not having these, as a function of OE as it stands, and when these didn't appear, as was the case that started this sub-discussion, that something had just 'gone wrong'. Surely, I wasn't seeing something different on my machine, than what everyone else was seeing, was I ? Presumably, once the post is on the server, I see the same as everyone else, don't I, even though it's my own post that I'm looking at ? I must admit to being a little confused now (not unusual !) The indicated bit of software is now installed, and I guess it must be doing something as you say that things now look "better", but I'm not sure exactly what I am seeing here, that looks any different, other than the number of right arrows at each line start seems to be increasing as you go further back ... ?? Arfa |
#33
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Cleaning Plated Electrical Contacts?
Arfa Daily wrote: Interesting that you say "often". I really hadn't noticed that this occured except on the odd occasion, and I had always put that down to there being something amiss in the formatting of the text that I was 'breaking into' with my comments. I don't very often reply in that way, answering individual points within the text body of the original post. Normally, I append a total reply to the bottom of the post, sometimes snipping irrelevant text from above or below, if it is one specific point that I am replying to, or where the post has become unnecessarily rambling. I had always thought that the original text gained right arrows at the start of each line automatically, with my text identified by not having these, as a function of OE as it stands, and when these didn't appear, as was the case that started this sub-discussion, that something had just 'gone wrong'. Surely, I wasn't seeing something different on my machine, than what everyone else was seeing, was I ? Presumably, once the post is on the server, I see the same as everyone else, don't I, even though it's my own post that I'm looking at ? I must admit to being a little confused now (not unusual !) The indicated bit of software is now installed, and I guess it must be doing something as you say that things now look "better", but I'm not sure exactly what I am seeing here, that looks any different, other than the number of right arrows at each line start seems to be increasing as you go further back ... ?? That's what its supposed to look like. Each new meassage is supposed to add another row of arrows to any quoted text, so you can tell who posted what without going back and reading every message in a thread. -- You can't have a sense of humor, if you have no sense! |
#34
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Cleaning Plated Electrical Contacts?
In article ,
"Arfa Daily" wrote: I must admit to being a little confused now FWIW I don't remember your posts having a quoting problem before. But I'm confused, too: I don't understand why so many people use an operating system that has to be patched every three days, and software that has to have third party **** added to it to work properly. |
#35
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Cleaning Plated Electrical Contacts?
"Michael A. Terrell" wrote in message m... Arfa Daily wrote: Interesting that you say "often". I really hadn't noticed that this occured except on the odd occasion, and I had always put that down to there being something amiss in the formatting of the text that I was 'breaking into' with my comments. I don't very often reply in that way, answering individual points within the text body of the original post. Normally, I append a total reply to the bottom of the post, sometimes snipping irrelevant text from above or below, if it is one specific point that I am replying to, or where the post has become unnecessarily rambling. I had always thought that the original text gained right arrows at the start of each line automatically, with my text identified by not having these, as a function of OE as it stands, and when these didn't appear, as was the case that started this sub-discussion, that something had just 'gone wrong'. Surely, I wasn't seeing something different on my machine, than what everyone else was seeing, was I ? Presumably, once the post is on the server, I see the same as everyone else, don't I, even though it's my own post that I'm looking at ? I must admit to being a little confused now (not unusual !) The indicated bit of software is now installed, and I guess it must be doing something as you say that things now look "better", but I'm not sure exactly what I am seeing here, that looks any different, other than the number of right arrows at each line start seems to be increasing as you go further back ... ?? That's what its supposed to look like. Each new meassage is supposed to add another row of arrows to any quoted text, so you can tell who posted what without going back and reading every message in a thread. -- Fair enough ! Mission accomplished then, I guess ... Arfa |
#36
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Cleaning Plated Electrical Contacts?
"Smitty Two" wrote in message news In article , "Arfa Daily" wrote: I must admit to being a little confused now FWIW I don't remember your posts having a quoting problem before. But I'm confused, too: I don't understand why so many people use an operating system that has to be patched every three days, and software that has to have third party **** added to it to work properly. Well, part of it is that I don't look good with a beard, or in sandals. I also find riding a bike a bit too much like hard work ... :-) Seriously though. My computers are just tools. They are not a hobby where I like to tinker with software and so on. I understand probably more than most average Joes about how they work, and how to keep them working, but the vagaries of operating systems and so on, are way, waaaayy over my head. For that reason alone, I just leave them with the Windows OS on them that they came with, but as a side issue, I like to know that if I buy or download a piece of software, chances are it can be thrown onto the machine, and will just work with a minimum of fuss. Gates-bashing seems to be an international pastime, and one that I don't really understand. OK, so the guy makes a lot of money, and some of his company's policies might be a bit monopolistic, but so what ? He puts a lot back into the community, and I really don't think that his business practices are any worse than many other large corporations. It also has to be remembered that pretty much single-handedly, that company has been responsible for spreading affordable and powerful computing throughout the world, from the poorest to the richest countries, and with a common platform that allows anyone from any of those countries, to develop software that can be used by pretty much anyone *with* a computer. As to it needing patches every couple of months, it has to be remembered that it is a large and complex piece of software, trying to please all of the people, all of the time. Of course there are going to be bugs, and as we all know, patching one - in any piece of software let alone an OS - is likely to cause other problems that just can't be forseen until they occur. Many of the patches are security-related, and wouldn't be necessary if the little toe rags who think it's funny to attack computers and wreak havoc in the commercial world, were properly targetted, and jumped on from a great height. Anyway, updating with those patches is no great shakes, is it ? My Windows machines check with MS regularly, and just get on with downloading and installing any updates, with little intervention from me. And before everyone starts squawking at me in self-rightous indignation for being crass enough to use, and actually *like* Windows, I really don't care. It does what I need it to do, without me having any deep understanding of either it, or the computers it runs on, and does it pretty much faultlessly the majority of the time ... d;~} Arfa |
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