> That's an old trick for cleaning open frame relay contacts.... use
> some paper.. newspaper is fine, where there is no ink. The paper has
> just enough abrasive quality to it to wipe off any oxide or dirt on
> the contacts, but it's not so rough that it will remove the metal of
> the contact itself. That was a second best technique, if you did not
> have a contact burnishing tool.
When the use of relays was more plentiful, we had special paper strips made for this purpose. Today, I would think strips cut from a coffee filter would be about the same.
For the benefit of newbies, I'd like to point out that 'in general', cleaning contacts, and burnishing contacts can be different. Metal migration is a problem in contacts. Metal from one contact will build up as a sharp spike on the mating contact. For this reason in manufacturing, the type of metal for each contact is often times chosen with the direction of current flow in mind to reduce the migration. The migration is proportional to the current and time in use.
I would expect the current flow in this keyer to be minimal, and a burnisher would not be required. For other applications, if you use paper to clean a contact that needs to be burnished, you will tear tiny strands of the paper that will be lodged in the contacts. Paper works good for contacts that are obviously dirty. You will see a small line on the paper from the dirt. It is best to follow up with burnishing if needed, or contact spray. When using spray, hold the contacts open while spraying, and until dry, to prevent a ball of residue forming where the contacts would have met. Blow them dry with compressed air of some type if possible. Consider that burnishers are microscopic files and will remove contact metal.
Paper or burnishers should NEVER be used on gold contacts of any type. Never touch gold contacts. (No erasers, either.) The gold plating on the contact surface is microscopic.
Richard Fjeld, NØCE
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