Robotics : 24495


Robotics / 24495

Subject:	Re: High Failure Rate of New Type 9V Geared Motor
Newsgroups:	lugnet.robotics, lugnet.technic
Date:	Sat, 22 Oct 2005 01:24:04 GMT
Viewed:	6908 times

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

Subject:	Re: High Failure Rate of New Type 9V Geared Motor
Newsgroups:	lugnet.robotics, lugnet.technic
Date:	Sat, 22 Oct 2005 02:43:28 GMT
Viewed:	7281 times

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

Subject:	Re: High Failure Rate of New Type 9V Geared Motor
Newsgroups:	lugnet.robotics, lugnet.technic
Date:	Thu, 27 Oct 2005 15:31:12 GMT
Viewed:	7669 times

In lugnet.robotics, Ross Crawford wrote:

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

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 don’t like them for their friction, their louder sound, and that they “feel” cheaper than the originals (weight, mostly).

Subject:	Re: High Failure Rate of New Type 9V Geared Motor
Newsgroups:	lugnet.robotics, lugnet.technic
Date:	Fri, 28 Oct 2005 01:31:32 GMT
Viewed:	8113 times

In lugnet.robotics, Jordan Bradford wrote:

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.

What a relief to know I’m not jinxed after all.

I don’t like them for their friction, their louder sound, and that they “feel” cheaper than the originals (weight, mostly).

And their high mortality rate.

I hope the proper person at TLC is looking into it.

C S Soh