comm cutting alternative?

[grunt95]

Well i had a bright idea of sanding off the black build up off my comm. I have been doing this for some time now and i was wondering if i am hurting any thing or if i should just keep doing what im doing?
The process
1. put arm in drill
2. sand with 150 grit
3. sand with 280 grit
4. sand with 320 grit
5. sand with 400 grit
6. sand with 600 grit
7. break in!
it works but im just looking for more of peoples opinions on this that use comm lathes to cut their comms.
Thanks
Grunt

[Colgout]

You can't have a true surface this way, and your brush could be jumping here and there. But I guess its better than not doing anything, I used to use eraser to clean the black carbon built up.

[grunt95]

so now why do you say that? Oh hey goo idea!

[TacoCrawler]

used to be that brushed motor distributors offered
commutator cleaners for sale.

Not really much different then using an eraser...
but they were designed and cut to fit directly into the brush shroud.

A small drill or another motor was coupled to one needing cleaning
and would spin the com/rotor while the tool was inserted.

Dan's RC, Peak Perf, Associated... etc.
were many options available back in the day.
One end was more abrasive...
and the other end was for a final clean up.

I'm not sure who might offer that now !?

Maybe Holmes Hobbies offers one !? :dunno:

Here's the one I used back in the day...

Peak Perf. com. cleaner

[Fergy]

I still have a Trinity com cleaning pen from the pre brushless days. Basically small fiberglass rods in a retractable pen that scrapes off the com without damage. It worked well.
If using sandpaper I would put it on something perfectly flat while spinning the com on it to keep it as flat and uniform as possible.

[Meatwad]

The one comm tool I've lusted for but have had no luck finding, my buddy Mr. Clanker has. So at least I get to borrow it.

Made out of some abrasive material, one end fits into the brush hood and is curved like the comm surface. The other end is rounded like a comm for brush cleaning. Old school racer guys have all the cool stuff...

[EddieO]

All the old comm sticks were was cratex molded to shape. You could make one yourself pretty easy out of a cratex stick. The dark reddish brown or the murky blue we're the two main compounds used...

You can make one out of a ruby red eraser as well for a couple of bucks.

The comm pens from trinity were simply a 3m fiberglass pen for auto paint touch ups. You can order online easy or just try an auto parts store or even Walmart.

As for the sandpaper.... God kills a kitten every time someone takes sand paper to a comm. Besides screwing up the arm most of the time, you are really not fixing anything....just a really crappy bandaid. Buy or borrow a comm lathe... Thy are dirt cheap now, seen em as cheap as $10.... And easy to use. I showed by blonde wife in 5 minutes....

Later EddieO

[WHITE-TRASH]

Once upon a time I had one of the aforementioned com sticks and it worked well enough. I lost it and resorted to using a drill and emery board and nothing but bad happened to my motors as amazing as that sounds. I broke down and bought a trinity com lathe awhile back for $20 and proceed to turn every single armature I could find.


Immoral of the story is listen to Eddie-O and buy a fawking lathe and treat your motors right!

[grunt95]

well thanks guys! looks like im doing more harm then help soo i see a comm lathe in my near future! once again guys thanks for chiming in.

[Meatwad]

Originally Posted by EddieO

All the old comm sticks were was cratex molded to shape. You could make one yourself pretty easy out of a cratex stick. The dark reddish brown or the murky blue we're the two main compounds used...

You can make one out of a ruby red eraser as well for a couple of bucks.

The comm pens from trinity were simply a 3m fiberglass pen for auto paint touch ups. You can order online easy or just try an auto parts store or even Walmart.

As for the sandpaper.... God kills a kitten every time someone takes sand paper to a comm. Besides screwing up the arm most of the time, you are really not fixing anything....just a really crappy bandaid. Buy or borrow a comm lathe... Thy are dirt cheap now, seen em as cheap as $10.... And easy to use. I showed by blonde wife in 5 minutes....

Later EddieO

Either you're liked more than I am or you know the right people, probably both. I can't find a decently priced comm lathe for crap, anything more than 50 buck is too much to keep my spare parts sporty going. All other rigs are bl now.

[Colgout]

Originally Posted by Meatwad

Either you're liked more than I am or you know the right people, probably both. I can't find a decently priced comm lathe for crap, anything more than 50 buck is too much to keep my spare parts sporty going. All other rigs are bl now.

These are all very reasonable price... If I am not already have one, i would have get the trinity one....

EDIT: The following lathes are for stock motor and are not the best option, you should look for one that has a V block or bearings to support the armature only, not the whole motor.

RC Car or Truck Cobra Stock Pro com 2000 Motor Lathe RARE RC Equipment AE HPI | eBay

Team Cobra 2000K Stock com Motor Lathe "Extra Cutters" | eBay

Trinity Tru Lathe Brushed Motor com Commutator Truing Kyosho Tamiya Associated | eBay

There are a few Hudy one too but they are close to hundred.

[Johnnysplits]

Not to hijack but, being that were on the subject and I've never owned a lathe and was on the "throw it out and buy a new motor plan", I have some questions:
- What do you look for to know that the comm needs to be cut?
- How often do you cut the comm?
- How many times can it be cut?

[The Violator]

Cleaning up the comm surface with sandpaper would remove way to much material without offering a nice flat surface. Plus without having access to brushes and springs to finish the clean up it would seem to be a waste of effort.


I know EddieO offers his rebuild services at reasonable rates. Plus he has all the parts to truly rebuild the motor. I have looked at lathes before, but in the end a pro rebuilt motor is a more consistent option. Plus while he has it, there are always new upgrades that can be done to make your used motor even better.

[badhoopty]

best comm cutting alternative?

brushless.

[dentonmac]

Originally Posted by The Violator

I know EddieO offers his rebuild services at reasonable rates. Plus he has all the parts to truly rebuild the motor. I have looked at lathes before, but in the end a pro rebuilt motor is a more consistent option. Plus while he has it, there are always new upgrades that can be done to make your used motor even better.

X2

Coming to crawling from the brushless go-fast world, I was crawling with some much more experienced crawlers. My rear motor in my MOA stopped, so one of the guys pulled just one of the brushes and said in a disgusted tone 'Do you do ANY maintenance?' With my puzzled look I knew it was a much needed lesson learned the embarrassing way.

I decided to purchase a comm lathe, I figured it was an investment in performance (as well as being pretty dang fun). My opinion, money well spent. With the amount of motors I have done, it paid for itself in just 3 motors (even with the very reasonable rates Eddie offers for rebuild). Compared to shipping, cost for rebuild, shipping back. And the more important (to me) down time.

[TEDROCKZ]

Originally Posted by Colgout

These are all very reasonable price... If I am not already have one, i would have get the trinity one....

RC Car or Truck Cobra Stock Pro com 2000 Motor Lathe RARE RC Equipment AE HPI | eBay

Team Cobra 2000K Stock com Motor Lathe "Extra Cutters" | eBay

Trinity Tru Lathe Brushed Motor com Commutator Truing Kyosho Tamiya Associated | eBay

There are a few Hudy one too but they are close to hundred.

All these you have linked are for stock/sealed can motors. Not what you want for the type of motors we have nowadays .

As for as the OP go ahead and buy the right stuff to do with and/or get someone that knows the right way to do it for you. The service and shipping to and from is relatively cheap compared to what good motors cost.

[WHITE-TRASH]

Originally Posted by TEDROCKZ

All these you have linked are for stock/sealed can motors. Not what you want for the type of motors we have nowadays .

No those lathes will work the same on any armature that'll fit on the fixture. My trinity lathe is basically the same and it hasn't had a problem with any com.

[TEDROCKZ]

Originally Posted by WHITE-TRASH

No those lathes will work the same on any armature that'll fit on the fixture. My trinity lathe is basically the same and it hasn't had a problem with any com.

Post a pic of a stock motor lathe with just the armature in it. Stock/sealed can lathes mount up the whole motor and turns the arm whilst in the can. Turns the comm through the brush way. Difference between stock motor lathes and mod motor lathes. Most manufacturers made both. Just not keen for turning just a uninstalled arm...

[WHITE-TRASH]

Originally Posted by TEDROCKZ

Post a pic of a stock motor lathe with just the armature in it. Stock/sealed can lathes mount up the whole motor and turns the arm whilst in the can. Turns the comm through the brush way. Difference between stock motor lathes and mod motor lathes. Most manufacturers made both. Just not keen for turning just a uninstalled arm...

I see my issue now, I looked at the picture on the box and saw a lathe that looks like mine not realizing they were the other type of lathes. I take the armature out of the can to turn the com. Never had an issue with it since I cut slowly removing as little material as I can with each pass.


For this application I don't see why either lathe type wouldn't work fine.

[ZippoMan]

Cool topic and I will mention I bought a Team Cobra lathe last year. I haven't even used it yet. I am too scared to try and also have not run my RC's enough to even attempt looking at the comms. If I had an old junker motor to practice with it would help. All my motors are Holmes Hobbies.