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GregS[_3_] GregS[_3_] is offline
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Default 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