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In lugnet.robotics, Chio Siong Soh wrote:
> Bad tidings! I'm experiencing a rather high failure rate with the new type 9V
> geared motor (#43362). This motor has been discussed before
> (http://news.lugnet.com/robotics/?n=19204&t=i&v=a)
>
> This motor can be easily recognised: when you twirl the shaft it turns very
> little and quickly comes to a halt. And it is lousy for doing the Magic Motor
> Test - connect an electric wire from one motor to the other. Twirl the shaft of
> one motor, the other motor should turn at almost the same speed.
>
> Out of 20 of these motors from 10 brand new RIS 2.0 sets, 6 motors have failed
> on me within less than a year. Some failed within just a couple of weeks. The
> common pattern of failure was that the motors will begin to turn slowly with a
> grinding sound, stiffened up and eventually will get jammed.
>
> A possible cause for this behaviour was given at
> http://news.lugnet.com/robotics/?n=19212
>
> I'm beginning to suspect that there is a design and/or manufacturing fault in
> these new type motors that should be drawn to TLC's attention. Or are they
> already aware of this? If so, why are they still putting them out?
>
> Would appreciate to know what is the experience of others just to be sure I'm
> not jinxed!
>
> C S Soh
I had the same problem with one of mine. Using them in a fast RC car might do
this if it gets slammed into something. I will inform Nathanael Kuipers of the
problem since he works at TLC and can tell the proper person.
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In lugnet.robotics, Nathan Bell wrote:
> In lugnet.robotics, Chio Siong Soh wrote:
> > Bad tidings! I'm experiencing a rather high failure rate with the new type 9V
> > geared motor (#43362). This motor has been discussed before
> > (http://news.lugnet.com/robotics/?n=19204&t=i&v=a)
>
> I had the same problem with one of mine. Using them in a fast RC car might do
> this if it gets slammed into something. I will inform Nathanael Kuipers of the
> problem since he works at TLC and can tell the proper person.
Thanks!
No, these motors were only used for FLL type challenges, not in fast RC cars.
I can submit the bad motors for *CSI* and 'autopsy' if need be.
C S Soh
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In lugnet.robotics, Chio Siong Soh wrote:
> In lugnet.robotics, Nathan Bell wrote:
> > In lugnet.robotics, Chio Siong Soh wrote:
> > > Bad tidings! I'm experiencing a rather high failure rate with the new type 9V
> > > geared motor (#43362). This motor has been discussed before
> > > (http://news.lugnet.com/robotics/?n=19204&t=i&v=a)
> >
> > I had the same problem with one of mine. Using them in a fast RC car might do
> > this if it gets slammed into something. I will inform Nathanael Kuipers of the
> > problem since he works at TLC and can tell the proper person.
>
> Thanks!
> No, these motors were only used for FLL type challenges, not in fast RC cars.
>
> I can submit the bad motors for *CSI* and 'autopsy' if need be.
>
> C S Soh
I sent Nathanael Kuipers an email regarding the motors and asked him to forward
it to the proper person.
Do you think it is excessive torque, excessive use, or just a bad piece design
that causes this problem?
Nathan
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In lugnet.robotics, Nathan Bell wrote:
> Do you think it is excessive torque, excessive use, or just a bad piece design
> that causes this problem?
I suspect it's bad design. Perhaps the way the brushes rub on the PCB as pointed
out by Philo (http://www.philohome.com/motors/motor.htm). "This higher friction
explains why 43362 stops faster when you give the shaft a twirl, and why its
no-load current is higher (9mA vs. 3.5mA)".
Its performance is degraded compared to the earlier motor (#71427). The only
advantage seems to be its lighter weight.
In previous posts misgivings have been expresed about this new motor which I am
now re-voicing:
http://news.lugnet.com/robotics/?n=19204
http://news.lugnet.com/technic/?n=8601
C S Soh
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In lugnet.robotics, Chio Siong Soh wrote:
>
> Its performance is degraded compared to the earlier motor (#71427). The only
> advantage seems to be its lighter weight.
I'm guessing it may also be cheaper / easier to manufacture.
ROSCO
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In lugnet.robotics, Ross Crawford wrote:
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In lugnet.robotics, Chio Siong Soh wrote:
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Its performance is degraded compared to the earlier motor (#71427). The only
advantage seems to be its lighter weight.
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Im guessing it may also be cheaper / easier to manufacture.
ROSCO
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I burned out two of these motors in a high-torque situation (my Great Ball
Contraption module prototype) which I posted about
here and
here.
I dont like them for their friction, their louder sound, and that they feel
cheaper than the originals (weight, mostly).
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In lugnet.robotics, Jordan Bradford wrote:
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I burned out two of these motors in a high-torque situation (my Great Ball
Contraption module prototype) which I posted about
here and
here.
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What a relief to know Im not jinxed after all.
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I dont like them for their friction, their louder sound, and that they
feel cheaper than the originals (weight, mostly).
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And their high mortality rate.
I hope the proper person at TLC is looking into it.
C S Soh
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