Märklin Brushes

(Apologies if this is a repeat; I thought I posted it but I can't see it)
I opened up one of my old Märklin locos (prototype: Swedish "Statens
Järnvägar" Da 884, 1955; model from ~1967) and one of the items I thought might be worth an overhaul was the brushes, so I took them out and to my surprise they were different from one another. One is a simple graphite rod (which is what I expected) but the other is made of what looks like rolled-up brass mesh. Is this "normal" in a 60's Märklin loco? Does it serve a purpose?
/Torsten
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I opened up my old Märklin loco (prototype: Swedish "Statens Järnvägar" Da 884, 1955; model from maybe 1967) to go over it for maintenance (see separate thread) and gave the brushes a closer look, as they seemed likely candidates for replacing. I found that the two brushes were different from one another. One is a length of graphite (which is what I expected) but the other is a rod of rolled-up brass mesh. Is this "normal"? If so, what's the purpose?
/Torsten
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Torsten Lif wrote:

Yes, it serves a definite purpose, although whether it's worthwhile is slightly debatable.
The bronze mesh brush is there to clean the commutator while the graphite one is slightly softer than electrically optimum so that it lubricates the commutator surface. In the 1950s Mä offered an alternative set of two (different composition) graphite brushes which they described as for slower running. (either Märklin fans weren't into slower running, or the graphite brushes didn't work as well because the brushes disappeared from the catalogue in the mid 50s)
If you look carefully when reassembling, you will find there is a slot in the graphite brush for the straight spring end to sit in and the other brush spring has a little "L" end which pokes into the bronze mesh brush.
I once tried using two graphite brushes but the result was a sooted up commutator which needed dismantling to clean.
Regards, Greg.P.
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Greg Procter wrote:

Cool. Thanks!

Yes, I noticed that.
I also noticed that they both were worn slightly at an angle but I can't figure which way they originally sat. :-(
But I'll try to get a new set anyway, so it doesn't matter much.

Don't want to go THERE!

/Torsten
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I forgot to mention, Maerklin did a general loco maintainence book released about 10-15 years ago. It may well still be in their catalogue
Torsten Lif wrote:

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