cleaning momentary push button switches

[Tony Duell]

> 
> Hi,
> 
> I've got an old piece of test equipment that has momentary push button 
> switches which are the primary "input" or control.  While most of them 
> seem to work, many of them are sticky, mushy, and just don't have a 
> positive click.

You haven't given us much to go on :-). There must me thousands of 
different types of pushbutton switches used on test equipment. A 
make/model of the equipnet and any markings on the switches could be a 
help. A description of the swtich would be useful...

Some swithces can be dismantled non-desturctively. If so, take them 
apart, you can then clean the contacts. Where you can restore the 'click' 
is another matter, sometimes bending some part will do it. FWIW, the 
meral from a coke can (or similar) can sometimes be used for make the 
'click washer'. 

Clean the parts with something lijke propan-2-ol (isopropanol). It 
doesn't attack most plastics, and it doesn't leave anythibng behind. I 
would not apply lubricants.

> 
> I'm not totally adverse to simply replacing them --- assuming I could 
> find an exact match.

That's what I would do, if I could get soemthing that would fit without 
modifications. Again, we'd need to know a bit more about the switches...

-tony