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Armature question????????

Armature question????????

Old 09-18-2005, 01:20 PM
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Default Armature question????????

I know that buying a replacement armature for your motor is much more cheaper than buying a new motor but would the pwer be the same? let's say that you always check your motors temp. and it never did overheat, any advice from the PRO's or anybody?

tnx in advance.
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Old 09-18-2005, 02:09 PM
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New armatures have a little bit more torque than one that has been cut a few times. The smaller the com gets, it advances the timing slightly which moves the RPM's a little higher and the torque down. It could possibly change your gearing. So no there is not much difference when you put in a new are vs. an older arm that has been cut, it just moves the power band of the motor a little lower in the RPM's.
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Old 09-18-2005, 09:26 PM
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Originally Posted by polesitter61
New armatures have a little bit more torque than one that has been cut a few times. The smaller the com gets, it advances the timing slightly which moves the RPM's a little higher and the torque down. It could possibly change your gearing. So no there is not much difference when you put in a new are vs. an older arm that has been cut, it just moves the power band of the motor a little lower in the RPM's.
That's truth
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Old 09-18-2005, 09:29 PM
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Originally Posted by polesitter61
New armatures have a little bit more torque than one that has been cut a few times. The smaller the com gets, it advances the timing slightly which moves the RPM's a little higher and the torque down. It could possibly change your gearing. So no there is not much difference when you put in a new are vs. an older arm that has been cut, it just moves the power band of the motor a little lower in the RPM's.


Another thing, I've heard that magnets lose saturation (strength) over time. So a newer motor should have more power since the magnets have more strength.
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Old 09-18-2005, 09:43 PM
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Originally Posted by ChadCapece


Another thing, I've heard that magnets lose saturation (strength) over time. So a newer motor should have more power since the magnets have more strength.
Just rezapped the magnet
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Old 09-18-2005, 09:44 PM
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Can anyone tell me what is a "good motor temperature"? like what temperature a 19T v2 element can run without "over heating"?
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Old 09-18-2005, 09:48 PM
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the only power difference between a new and old armature ( i am assuming that you are talking about a stock motor? or 19T?) will come from the comm size, and the strength and integrity of having an arm with new wire (wire that has never been run).

the comm size does effect power, as the comm gets smaller (this as a result of truing on a comm lathe) the brushes can wrap father around the comm. this results in decreased efficiency, and increasd power. the comm size has no effect on the timing of the motor.

the magnets do lose their power over time, it is a good idea to get the zapped every once in a while.

my suggestion, if you are into racing, and need a motor that is perforing at its best, then just buy a brand new motor. if you are just bashing around, you'll be able to get by on just a new arm.

peter robinson
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Old 09-18-2005, 11:07 PM
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I'll second Peter's view on getting a new motor.

For the cost of getting a replacement arm another few more tens,you get a new end bell,new motor springs,new brushes and a new motor can.I thinks thats a better deal...

Don't you think so??
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Old 09-19-2005, 08:03 AM
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PHP Code:
the comm size has no effect on the timing of the motor 
????
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Old 09-19-2005, 08:19 AM
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Peter let me correct you just a bit. The comm size does affect the timing. I will explain.... as the com get smaller the brush wrap increases. as the brush wrap increases the leading edge of the brushes moves in the advancing direction while the trailing edge move in the retarding direction. This movement is minor but it does exist. While the mechanical timing of the endbell didnt change with relationship to the magnet the firing point of the armature does with relationship to the magnets.
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Old 09-19-2005, 09:08 AM
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John dropping knowledge...
and yes, he is correct, ask any of the oval guys...

First thing they do with a new motor is cut it WAY down to increase the RPM
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Old 09-19-2005, 09:20 AM
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To save money I just recopper my comms and cut the comms to the size I want. The comms last much longer and give much more rpms.

Ronald
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Old 09-19-2005, 12:57 PM
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Originally Posted by mooony
To save money I just recopper my comms and cut the comms to the size I want. The comms last much longer and give much more rpms.

Ronald
where can you get them coppers? abd how much do they cost?
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Old 09-19-2005, 03:04 PM
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It increases timing in theory.......Big Jim always maintained it did not......by that theory, a large comm stock would never work, since it would have less timing....but I can show you a prototype that would prove that theory wrong.

And also by that theory, using a larger brush that wrapped even more fully around would have even more timing.

Timing mechanically is set in two spots....the can/endbell, and the comm slots....

Smaller comm= More RPM......

Larger Comm= More torque...

And compare nothing to what the oval guys do.....they are a unique crowd with some unique ideas and theories....

Later EddieO
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Old 09-19-2005, 03:04 PM
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www.fussybrush.com

Thats where you can buy the replacement comm stuff....

Later EddieO
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