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shuter
2006.08.03, 05:54 PM
years ago when I used to slot car race I used to open the case and smooth and polish the commutator with crokus cloth. (I doubt thst is how you spell it) I would then use an Exacto knife to carefully clean out the grooves. It really did a fine job keeping the commutator running efficiently. I am about to drill a hole in the plastic end cap for commutator cleaning on my HFAY car since the rules do not permit opening the can. The hole will allow only limited access for cleaning. What is the best way to condition and clean the commutator under these conditions? What are you guys doing?

nivlacs3z
2006.08.03, 07:12 PM
I dont think its a good idea to use a knife and clean the groves. What I do is just take a napkin, hold the comm in the napkin, and twist. The reason I say that I dont think its a good idea is because you could offset the groves. The two have sort of adapted to eachother in that they have lapped each other to make the same groves on both the comm and the brushes. If its possible then have a hole large enough to partially fit a Q-tip down (with some cotton taken off) and just twist the comm on that. I bet that'd work. GL

shuter
2006.08.03, 07:36 PM
I dont think its a good idea to use a knife and clean the groves. What I do is just take a napkin, hold the comm in the napkin, and twist. The reason I say that I dont think its a good idea is because you could offset the groves. The two have sort of adapted to eachother in that they have lapped each other to make the same groves on both the comm and the brushes. If its possible then have a hole large enough to partially fit a Q-tip down (with some cotton taken off) and just twist the comm on that. I bet that'd work. GL

Yes, one needs to be careful when cleaning the grooves so as not to disturb the edges of the groove. A razor blade or thin exacto knife used carefully can clean them out without doing so. The grooves can build up material from the commutator and brushes that will conduct electricity. I always felt that the grooves were engineered to be non conductive and tried to maintain the engineering.

After running for a while the commutator gets concentric imperfections as well as coated with brush material combined and scum buildup. Isn't it a performance advantage to keep it clean? Do comm drops soften stock brushes and promote this buildup?

Sinister_Y
2006.08.03, 08:13 PM
Shuter,

Same deal here, back in 1/10 and I do this now with mini-z motors is to use a comm stick (looks like a double eraser, cylindrical on one side and rectangular on the other). Then cleanup the crap between the grooves with an exacto knife. Like mentioned, care is needed.

I know some guys who use an actual comm lathe instead of a comm stick.

Comm drops will crap up the comm and could affect the arcs going from the brushes to the comm, i.e. rob power after a while. A trick we used to do in 1/10 and could be used for any racing with electric motors, is to use the comm drops, then after the heat, motor spray (i.e. read non-chlorinated brake cleaner), lube any bearings/bushings and then reapply comm drops. Works good and you still get good power each time.

shuter
2006.08.03, 11:46 PM
Shuter,

Same deal here, back in 1/10 and I do this now with mini-z motors is to use a comm stick (looks like a double eraser, cylindrical on one side and rectangular on the other). Then cleanup the crap between the grooves with an exacto knife. Like mentioned, care is needed.

I know some guys who use an actual comm lathe instead of a comm stick.

Comm drops will crap up the comm and could affect the arcs going from the brushes to the comm, i.e. rob power after a while. A trick we used to do in 1/10 and could be used for any racing with electric motors, is to use the comm drops, then after the heat, motor spray (i.e. read non-chlorinated brake cleaner), lube any bearings/bushings and then reapply comm drops. Works good and you still get good power each time.

I bought some comm drops but have not used them yet for fear of gumming up the commutator. With these little cars, I wonder if I can spry the motor without getting it on the tires or into the electronics? Is there a comm stick that will be small enough to fit through the hole I'm thinking of drilling in the plastic end cap?

gasman1
2006.08.04, 08:57 AM
Shuter,

Same deal here, back in 1/10 and I do this now with mini-z motors is to use a comm stick (looks like a double eraser, cylindrical on one side and rectangular on the other). Then cleanup the crap between the grooves with an exacto knife. Like mentioned, care is needed.

I know some guys who use an actual comm lathe instead of a comm stick.

Comm drops will crap up the comm and could affect the arcs going from the brushes to the comm, i.e. rob power after a while. A trick we used to do in 1/10 and could be used for any racing with electric motors, is to use the comm drops, then after the heat, motor spray (i.e. read non-chlorinated brake cleaner), lube any bearings/bushings and then reapply comm drops. Works good and you still get good power each time.

How do they fit a 130 armature on comm lathe made for 1/10 scale. I sure would be interested

Sinister_Y
2006.08.04, 04:13 PM
Shuter, I always rebuild my cars before and after a race, so this means a complete strip down. This is when I cleanup the com and stuff, check the brush wear etc... (and clean and relube my wheel bearings etc...) and clean the motor can. Regarding the actual heats/race, just use the stick (like a straw) that is included with the can to direct the spray or take the motor off and do it. You want to usually spray in through the area where the brushes are (for the rebuildable motors like atomic and the new PN BB can). For sealed (which can be opened of course) like the Xspeed, most PN and some other motors, I know that PN has a hole where you can spray or put comm drops (i.e. they've drilled a whole into the white plastic endbell housing). Getting brake cleaner (has to be non-chlorinated or you've melt all plastic parts!) on stuff will not harm it, including your tires. At the worst getting brake cleaner on the tires will dry them out a little, so to fix there are few solutions, apply a little bit of traction compound on the tire to get it lubed again, use a cloth/rag around the motor can to avoid excessive spray when cleaning the can and lastly an old 1/10 and 1/5 scale trick I used to use. Clean the tires with soap and water (and toothbrush). It works amazing to restore the rubber to be very sticky. Oh yeah regarding your Q on the stick. You gotta take the motor apart to do this. The other option is if it is a rebuildable, then you can desolder the brush assemblies and use the stick and then resolder back.

Gasman, I have not seen my friends actually use the comm lathe on the mini-z motors, but they wouldn't lie to me. I wouldn't go out and buy one myself as the stick will work fine. It's just to clean up the comm. most times these motors are so cheap, you throw out the old ones...to new ones anyway, stronger magnets (unless you have a magnet zapper...again 1/10 stuff) etc...

shuter
2006.08.06, 09:49 PM
Sinister_Y - Thanks for the input

Sooooo.... Nobody is doing any commutator maintenance on their HFAY cars?

builthatch
2006.08.06, 10:44 PM
i clean my comm with an eraser, then i clean the eraser crap out of the comm slots with an xacto. the final move will be a thorough spraying with motor spray.

also, i've found that using a silver brush on the positive side seems to help keep the comm nicer than a full carbon setup.

gasman1
2006.08.07, 09:52 AM
Sinister_Y - Thanks for the input

Sooooo.... Nobody is doing any commutator maintenance on their HFAY cars?


That is going to be very difficult to do since your not allowed to open the motor can.

Drill a hole in the plastic endbell to be able to get motor spray in to clean motor. Re-oil the bearings. Its not the best way, but it's better than nothing. Just watch when you drill the hole that you don't hit the comm. :eek:

imxlr8ed
2006.08.07, 11:56 AM
I use Reedy motor spray (aimed at the 2 little square holes), and oil the bushings afterwards... been running the same motor since my first HFAY TT back in... December ?!?! No problems to report as of yet !

(hope I didn't just jinx it :o )

Oh yeah, I also run with a cover over those holes when I race... the motor is basically sealed shut when it's in the car.

shuter
2006.08.07, 06:05 PM
Builthatch - Later on when I get into modified motors I'll keep the silver brush on the positive side in mind. Right now I am experimenting with various setups for HFAY and learning to drive. Still have not figured out how to get around the short 180's with any speed. Its killing my times.

Gasman - Yes, drilling the comm sounds like something I might do :eek: A friend has a drill press, I believe I'll use it.

imxlr8ed - Clean is good... I'll try the tape. :D

Thanks

gasman1
2006.08.08, 07:00 AM
Builthatch - Later on when I get into modified motors I'll keep the silver brush on the positive side in mind. Right now I am experimenting with various setups for HFAY and learning to drive. Still have not figured out how to get around the short 180's with any speed. Its killing my times.

Gasman - Yes, drilling the comm sounds like something I might do :eek: A friend has a drill press, I believe I'll use it.

imxlr8ed - Clean is good... I'll try the tape. :D

Thanks

I don't us a power drill or a drill press to drill the hole. You can start with a sharp X-acto knife to start the hole and then use thumb drill bits to enlarge the hole to what you want it to be. Be careful of hitting the comm and flush the motor out with motor spray when your done to remove any of the plastic bits from driling the hole.

Also, I wouldn't cover up any holes on the motor can. The stock motors have very little ventilation and the design of the stock motor mount closes the motor up to hold the heat in the motor. Hot motor = lost performance!

shuter
2006.08.09, 09:04 PM
imxlr8ed - You say you cover the motor holes when you race. Gasman has a point about heat. Although I am not running any stock motor mounts so I have pretty good ventilation. How are you covering the holes? Tape?

Gasman - Seems like the drill press is the most controllable way to drill. I have complete control over depth, and slowly applying pressure to one drill would seem to be the most likely way to keep plastic from dropping inside. Don't you think?

gasman1
2006.08.10, 09:32 AM
imxlr8ed - You say you cover the motor holes when you race. Gasman has a point about heat. Although I am not running any stock motor mounts so I have pretty good ventilation. How are you covering the holes? Tape?

Gasman - Seems like the drill press is the most controllable way to drill. I have complete control over depth, and slowly applying pressure to one drill would seem to be the most likely way to keep plastic from dropping inside. Don't you think?

I'm not saying the drill press isn't a good way to do it, I just explained how I drill my holes. I have more control and I can feel when the bit breaks through better when doing it by hand so I don't damage the comm.

imxlr8ed
2006.08.10, 10:26 AM
I have a thick piece of paper as a shim under my stock motor clip, it's long enough to cover the holes.

I do know that this does kill the longevity of the motor, but then again... I've been running it this way every HFAY and it is still going strong to this day.

shuter
2006.08.11, 12:43 AM
I have a thick piece of paper as a shim under my stock motor clip, it's long enough to cover the holes.

I do know that this does kill the longevity of the motor, but then again... I've been running it this way every HFAY and it is still going strong to this day.


With an uncovered motor, All the grit that gets in there can't be good for it either. Think I'll give it a try and see how hot my motor gets.