RE: [CAD_CAM_EDM_DRO] Stepper motor from Sherline?

The most common value quoted is the holding torque. I would agree that on
paper it looks like a great motor for a Sherline sized machine. The voltage
rating is nice and low so it is easy to get a high enough voltage with a
chopper drive for a good max RPM. The only thing that seems odd is the size
(length) seems very short for a motor of this holding power. OTOH, there are
rare earth magnet motors now that have incredible output for the size.

Tim
[Denver, CO]

> I posted this on the Sherline group without response, so on the chance
> there are any Sherline CNC'ers over here that aren't over there, I'll
> repeat it here:
>
> Has anyone used the stepper motor Sherline sells? (I wasn't
> even aware of
> it until last week--they seem to have added it to the price
> list without
> fanfare...)
>
> I called and asked about specs, and from what the guy said I
> tracked it
> down to a Shinano Kenshi SST57D3201. Data sheet is at
>
> http://www.shinano.com/pdf/SST57D.pdf
>
> It is a 2-amp size 23 motor, double 1/4" shaft, 134 oz-in
> holding torque
> and about 95 oz-in pull-in torque. On paper, it looks like a
> really nice
> motor.
>
> The Sherline listing is
>
> 67130 STEPPER MOTOR, 2-amp, 23 Frame, 100 oz-in stall torque $48.00
>
> That seems to be about surplus price for a motor of this
> spec, from the
> ones I can find.
>
> BTW, when people talk about a "100 oz-in" motor, are they
> speaking holding
> or stall torque? I can rarely find data sheets for stepper
> motors listed
> on the surplus pages (like
> http://members.home.net/genea/StepperAndServoMotors.html )
>
> Best regards,
>
> Randy
>
> Randy Gordon-Gilmore ,----.___________ ______________
> _________________
> ProtoTrains // = = === == || == == == = || ==
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> Rio Vista, CA, USA
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