# What part exactly is the "comm"



## dennis07 (Dec 7, 2011)

I recently pulled my 1967? T-Jet 500's out of the closet. First time I've opened the box in over 40 years. So I've been to several websites and read this forum for hours. I keep coming across the term "comm". In the parts blow-out of the T-Jet it doesn't mention "comm" as a part. I'm sure all 7 of my cars need to have the comm cleaned as described in so many posts now I just need to figure out what it is. 
As long as I'm asking for advice-- The stock magnets with my cars are all black. There are no marks to indicate North and south. As a 10 year old I had no idea the magnets were suppose to go in a certain way (probably explains why the cars didn't run so well at times). How do I go about finding a North and south magnet out of the ones I have for each car?

Thanks for helping a newbie.


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## alpink (Aug 22, 2010)

commutator. it is the three segment copper plate on the bottom of the armature on pancake motors.

get a boyscout compass to determine polarity of the magnets. put the magnet against the compass like it is snuggling with it and center the "c" at the N on the compass, if the longer part of the pointer is on the N, it is the north magnet.


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## dennis07 (Dec 7, 2011)

thanks for the quick reply.


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## HO_Only (Jan 30, 2011)

*North magnets go in the front*

The North/South orientation of the magnets effects the direction the will car run. North magnets go in the front. Turning them upside down might effect performance. The only way to tell which way is best, is trial and error…


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## Sir Slotsalot (Jan 23, 2010)

I thought the "comm" was control of the helm on a Federation Starship. LOL!! Sorry I couldn't resist. Too much Trek.


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## slotking (May 27, 2008)

dennis, sorry about the joke postit by Sirslot!

on a serious note, with a car tht old, you need to check and make sure there are no cracks in the dilithium crystals!

it can be very bad


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## Boosted-Z71 (Nov 26, 2007)

That smell of 30+ year old Aurora oil would be the stuff slot car dreams of made of, 1 wiff would take any of us back to our child hood days.

The magnet deal is easy if your just racing at your own track, if the car runs backwards switch the magnet positions in the chassis.

Boosted


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## dennis07 (Dec 7, 2011)

"That smell of 30+ year old Aurora oil would be the stuff slot car dreams of made of, 1 wiff would take any of us back to our child hood days."

It has been cool seeing this stuff again. I took an axel out of one car & cleaned off 40 year old lint. Is there a market for vintage lint?
Live long and prosper
Dennis


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## Boosted-Z71 (Nov 26, 2007)

Sorry Dennis, I dont think the lint and axle crud ever caught on, at least not on the same scale as the burning oil smell. Glad you dug out the old cars, hope your get them running like the day they were new and enjoy them twice as much now, I know I get the biggest kick from running some of the originals that I have.

Boosted


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## slotcarman12078 (Oct 3, 2008)

Oh and if you're lacking a compass, you can match up magnets by how they attract to each other. A set of mags will go together like this.... () Same pole magnets will do this... (( . One of each pole in a car should get it moving. Reverse magnet positions if the car goes backwards. Oh, and sort the rest in piles so you know which are which once you establish and sort them out.


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## dennis07 (Dec 7, 2011)

Thanks slotcarman. I asked someone selling magnets on ebay for advice before I posted here & they replied a day or so later with the same advice. I've got them all sorted. Surprisingly to me out of my 9 sets of magnets I only had 1 set that was not matched. I had one extra magnet so it was the odd ball. I'm waiting for a new old transformer to arrive and I'll start test driving. In the meantime I've been washing & waxing-- seriously--the bodies and giving all of the parts a good cleaning. It's amazing what a soft metal wheel and a dremel can do for worn out looking pickup shoes.
Dennis


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## Bill Hall (Jan 6, 2007)

How many times we gotta go over this?

That aint fuzz, it's an oiling wick!


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## Boosted-Z71 (Nov 26, 2007)

Bill Hall said:


> That aint fuzz, it's an oiling wick!


I just never thought of it that way, but I will from now on :wave:

Boosted


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