High quality 7-pole motors .... very, very, cheap

[Peaky 556]

Just suggesting maybe the title of this thread is a little overstating of the spec of these motors...  Now John may well have been misled on this description, so I am not trying to conduct a witch-hunt, just to present some facts.
·        Firstly, as John Branch has pointed out in the newsletter, the brush gear is very basic, comprising a spring that, alone, holds the carbon brush in the general proximity of the commutator.  There is no attempt to have a heat-sink or heat removal path, instead the heat from the brush has to travel through the spring coils to get away.
·        Secondly there are five poles, not seven.
My view, gaining some momentum, is that these are low-duty motors, and that overly enthusiastic running or excessive current will cause overheating of the brush springs, followed by relaxation, more arcing, and more heat.
Results from any testing of these motors in a real environment, ie train pulling not just light engine running, would be very welcome if anyone has any?
For instance, John, - do you have any performance experience for the Sentinel with a load of coal trucks?
Regards,
Tim

[John Candy]

Tim,

As you have said, the spec. I listed for these motors is that which was provided by the vendor.
Since the motors are totally encased, I cannot comment on the number of poles (and I am away at present so cannot inspect a sample).

I have only run "Plantagenet" on the rolling road (apart from the short video clip elsewhere in this forum) but "Arthur" spent time running on "Mangapps" at the AGM, hauling a GRS coach.

  The same motor has (I am told) been fitted by Walsall Model Industries  to their own gearboxes for several years and that it how I came into contact with these motors.....the two motor/gearbox units fitted to the Sentinels were standard WMI stock obtained by Ian T.

Cannot add much (if anything) to these observations.

John.