Go Back  R/C Tech Forums > General Forums > Electric On-Road
How small is too small...commutators? >

How small is too small...commutators?

How small is too small...commutators?

Old 01-28-2007, 02:14 PM
  #1  
Registered User
Thread Starter
iTrader: (25)
 
Dasupacat1's Avatar
 
Join Date: Aug 2005
Location: Fort Wayne, IN
Posts: 1,372
Trader Rating: 25 (96%+)
Default How small is too small...commutators?

How small is too small when cutting your comms? Is .270 the limit for regular comms? What about large comms like on a Reedy?
Dasupacat1 is offline  
Old 01-28-2007, 02:32 PM
  #2  
Tech Master
iTrader: (26)
 
sportpak's Avatar
 
Join Date: Oct 2006
Location: Ft Wayne, IN
Posts: 1,314
Trader Rating: 26 (100%+)
Default

Word up Dave.. I've heard .260/.265. I have one at .268 and seems to run pretty decent still. I'm not a motor-head, but it runs pretty good. Trust the seat of your pants. Ask big Phil on Tuesday. He's an old wiley veteran at motor tuning.
sportpak is offline  
Old 01-28-2007, 02:34 PM
  #3  
Super Moderator
iTrader: (217)
 
Marcos.J's Avatar
 
Join Date: Sep 2003
Location: Semper Fi
Posts: 31,207
Trader Rating: 217 (100%+)
Default

Originally Posted by sportpak
Word up Dave.. I've heard .260/.265. I have one at .268 and seems to run pretty decent still. I'm not a motor-head, but it runs pretty good. Trust the seat of your pants. Ask big Phil on Tuesday. He's an old wiley veteran at motor tuning.
.264
Marcos.J is offline  
Old 01-28-2007, 02:36 PM
  #4  
Tech Master
iTrader: (14)
 
Join Date: May 2005
Location: michigan
Posts: 1,678
Trader Rating: 14 (100%+)
Default

I've noticed many stock motors can start to suck past .270, losing lots of torque and efficiency.
o.s. power is offline  
Old 01-28-2007, 02:44 PM
  #5  
Tech Lord
iTrader: (22)
 
UN4RACING's Avatar
 
Join Date: Oct 2006
Location: MODIFIED!
Posts: 13,140
Trader Rating: 22 (100%+)
Default

Whats wrong with you guys. True that baby til it peels off.
UN4RACING is offline  
Old 01-28-2007, 02:53 PM
  #6  
Tech Elite
 
PitCrew's Avatar
 
Join Date: Sep 2003
Location: Seattle Indoor Raceway
Posts: 2,129
Default

When you go much past .270, you risk peeling the comm off. No big deal if you don't mind blowing up your diamond bit and getting hit in the face with an armature.

Also, when you are down that small try narrowing your brushes a bit. The increased surface area of the brush wrap increases the dead area that is shorted.

Try this. Comm diameter divided by 2. So, a .270 comm you should narrow your brushes to .135. Then you will have perfect wrap with no shorting.
PitCrew is offline  
Old 01-28-2007, 03:10 PM
  #7  
Tech Regular
 
Join Date: Sep 2005
Posts: 454
Default

Can someone tell me what it is in mm?

Thanks.
trf_racer is offline  
Old 01-28-2007, 03:20 PM
  #8  
Tech Elite
 
PitCrew's Avatar
 
Join Date: Sep 2003
Location: Seattle Indoor Raceway
Posts: 2,129
Default

.270 / .03937

6.86
PitCrew is offline  
Old 01-28-2007, 04:16 PM
  #9  
Registered User
Thread Starter
iTrader: (25)
 
Dasupacat1's Avatar
 
Join Date: Aug 2005
Location: Fort Wayne, IN
Posts: 1,372
Trader Rating: 25 (96%+)
Default

What about big comms?
Dasupacat1 is offline  

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.