ummmm,,, uhhh ooo, please help! rcca people!

[mavrick0611]

ok i just got my new comm lathe today, i read the directions, and cut the comm, when i was done it looked nice and shiny except for were the comm is split into the sections. Around those sections it looked as if a layer was pelled off. i can try to get pictures later.

i then reasembbled the motor dropped in new brushes and went to break in the brushes i would throttle it up it would sound normal then it would start whinning, and not acting normal. like it would rev up and near full throttle or reving quickly it would start screching, whinning, and giving high pitch sounds.

so whats going on? did i cut it wrong? does it need re cut or something????

please help!

[ 06-12-2001: Message edited by: mavrick0611 ]

[bullfrog]

i think u cut it too thin .... that sound your hearing is the armature wobbling around in the can.....well its our first job everybody makes mistakes somtimes..looks like your gonna have to geta new armature.

[mavrick0611]

whay would the amiture wobble if i cut the comm?

[XXXER]

It sounds like you are taking off too much of the comm in one pass, you need to take a lot of passes, I mean, you should just BARELY skim the comm each pass.

It could very well be toast, you may need to replace it.

[bullfrog]

the comm is connected to the armature and the comm buzzing in the bushings causes the whole armature to wobble.your lucky the armature didnt get so battered around that it exploded ive seen it happen a guy at my local slot car track cut his comm too thin ( this was a super hornet)and all i heard was a whining sound then a buzzing sound then a pop and i looked over and the whole motor was smoking it litterally disenigrated the magnets and the can had a whole bunch of dents in it ( it looked like it got shot up with a bb gun)and he spent bout an hour cleaning up ( and putting on band aids ) cuz some of the parts went into the side of his hand..... nuf said.

[ 06-12-2001: Message edited by: bullfrog ]

[mavrick0611]

ooo,,, well i changed brushes to older ones and tried it it didnt do it as much but still did it, after about 15 minutes i i put in the new brushes and it only did it once. so i put it in my car and drove 3 packs through it and it was like new, maybeit was just rough or something???? i dont know ill have to read up more on this subject.
aj

[bullfrog]

mabey the new brushes r what is keeping it from wobbling did u change the springs? or mabey the worn brushes made it wobble?

[WhoKnowsWho]

I remember in an old RCCA, they marked the comm with a sharpie marker... so once the sharpie marker black went away, it was cut true and put back in... and new springs wouldn't hurt either probably!

[mavrick0611]

i put in new burshes. It acted fine after running it for about 20 minutes,,, maybe i just didnt make a fine cut. The springs are nearly brand new. i read about that marker tip i forgot to use it though after i run it today ill try truing it again.

thanks for the help!
aj

[B3 Bomb]

<font color="#0000FF">Next time after cutting it take a ball point pen and
run it down the three lines on the comm.&nbsp; This will stop the brushes from
getting hung up or from peeling the next time you cut it.&nbsp; Works for me!</font></p>
http://www.plauder-smilies.de/imu2.gif

[mavrick0611]

hum, didnt think about that, maybe thats what the problem was! well im going to cut it again tonight, its a 10 turn and there will be like 7 runs or better on it so you know,

thanks for all the help!

aj