Ball screws are nice but expensive. We have

more friction and reduction

so I hope this does not happen to us. I would

hate to have to readjust

the prop if the RPM creeps up.

Is that Pittman motor a permanent magnet motor?

 If so, design a

provision in

the circuit to short the motor.  That will

'brake' the motor and prevent it

from rotating.

Marc Pedings

Thanks Marc. Good idea. I will bet that will

works on yours too Jeff.

Will it really "stop" the motor or just slow it

down?  We use an

electromagnetic brake.

Jeff Spitzer

Given the additional friction we won't know until we
try it Jeff but
Tracy has agreed to try it on his test stand.

Paul Lamar

A shorted permanent magnet DC motor resistss movement
by back EMF. No movement - no back EMF - it will only
slow the creeping. You can see this directly if you or
a friend have one of these So African spring driven
radios - turning it off shorts the motor which is
being used as a generator - the handle slows - but it
does not stop - Vance

 
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