# Comm size????



## me21 (Nov 7, 2003)

What is the smallest you have cut a comm down to? Is .269 starting to push my luck? I hear alot of people say .270


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## tfrahm (Nov 14, 1998)

ONE time I managed .267, but the motor didn't run long before burning through the thin comm segments... Normally it's .270 for me...


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## RCMits (Jan 1, 1970)

me21 said:


> What is the smallest you have cut a comm down to? Is .269 starting to push my luck? I hear alot of people say .270


270 is the best.. if you got some soldering skillz.. you can check our fyssybush and their commsleeves.. pretty nifty.

i had one comm at 268 once.. but it just acted wierd.


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## Slider (Dec 7, 2003)

269 But it don't last long, to thin


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## erock1331 (Apr 1, 2002)

.265 but on the track it was unpredictable, 
Usually anything under 2.70 is either a track record pace motor or acts funny and wont run worth a crap, usually you can tell on break in if it will run or not.
Just feel the motor, it tells you alot, LOL as Mr. Peachock always told me.


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## erock1331 (Apr 1, 2002)

The biggest thing to worry about on a small com is damaging the bit on your lathe when they get that low.


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## BrentP (Mar 1, 2002)

I've cut a couple down to .265 & they run like a banshi on the track for about 40 seconds then they fall off hard. The copper is so thin that it heats up very fast & either will come apart or fall on its face. Like erock said, it is a very dangerous situation for your lathe to go below .270. If it digs into the bit you could ruin an $80 diamond bit real fast.

__________________
Brent Pearcy
Bulit Motorsports, TQCells


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## 22Racer (Nov 18, 2001)

.270 is the common dia to stop and throw it away. I hate the way they run under .280. I've been installing Fussybrush comm sleeves for guy's for $10.00 including shipping back. Big savings on a hand wound mod! I love the way a larger comm feels. I like them better than a new motor, and they run nice and cool. With the comm sleeve you can get a comm as big as .315 
Rex e-mail [email protected]


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## EddieO (Sep 19, 2003)

.270 is the safe bet.....anything else you are playing with fire...

The bigger .350 comms, you can go a little more than .030......like .310 to .315....

Later EddieO


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## SlipNSlide (Jul 6, 2004)

Is it true that the smaller the comm size gets the more you should narrow the face of the brush to prevent too much overlap?


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