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Discussion Starter #1
Dumb question about grease,
As I need to reassemble my brushes I thought I would get some electric motor grease,
Several people appear to recommend “Noalox” – damned if I can find it in New Zealand!

Looking into it I think I find;
Grease is non-conductive,
“Noalox” has zinc particles in it, “Coppaslip” has copper particles in it
Neither is more than slightly conductive

Adding small particles that can be crushed between the surfaces strikes me as being analogous to improving your bearing by adding swarf

I can buy an even lower conductivity grease –Dielectric Grease – at a huge increase in price

The main thing the grease does it to provide a protective coating to keep water and air off the metal, when crimping or bolting together it may enable the metal parts to “slide” into a better joint .

So on my motor and on my crimped joints I should use a good high melting point normal grease??
(Not silicon as that has some adverse effect on brushes)

Am I blowing smoke?
:confused:
 

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questions are always good. . . :)

Conductive greases use particles of different types of conductive metals..usually ones that are resistive to oxidation and fairly good conductors. The idea is that under high compressive forces, the small particles are "squashed" making contact with both surfaces ensuring a good electrical connection. The grease is the material that holds it in suspension and keeps out the atmosphere. The better types use silver bits, others use zinc etc.

Major may want to chime in here.. but my thoughts are to not use anything on brush to commutator "connection" ... if that is what your are proposing. A natural "film" develops here as brushes wear in and seat.... and u don't want to mess with it. As for the other compressive connections related to a motor... I suppose it could be used.

Cheers,
Gary
Edit... "dielectric" means non-conductive... don't be using this on anything that you want a good electrical connection with.
 

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Dumb question about grease,
Hi Dunc,

I don't particularly like the stuff for electrical connections. The only times I use it is on Pb-Acid battery terminals and for Aluminum connectors. For copper or brass in a noncorrosive environment, I go dry with a rubber boot.

And never put any chemical in the motor.

major
 

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Discussion Starter #4
Thanks Major,

So for the screws that connect the brush tails,
The brush tails, the copper bits they screw onto
and for the leads on my motor I should clean the parts and connect them dry?

When I get around to doing the crimps - dry as well? - with heat shrink and glue
 

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Thanks Major,

So for the screws that connect the brush tails,
The brush tails, the copper bits they screw onto
and for the leads on my motor I should clean the parts and connect them dry?

When I get around to doing the crimps - dry as well? - with heat shrink and glue
That is what I recommend. Works for me :) Rubber boots are nice for outside exposed terminals.
 
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