Re: [CAD_CAM_EDM_DRO] Stepper sings, but wont walk....

audiomaker2000 wrote:

> Hey all,
> I have been trying to repair a Bridgeport Boss that has a stepper
> which when told to move via the stock control "sings" and will sort
> of vibrate but wont actually turn. I've replaced every card in the
> machine with those which I pulled from my retrofit machine (and
> which are known to work), and the result is the same. I checked the
> motor itself by switching it to a different axis circuit and the
> stepper works fine.
> So, I'm wondering what else besides the cards (drives, and stock
> CNC) that could cause such a condition? I'll probably just retrofit
> this one too, but it is making me quite curious. All that seems to
> be left is cap's and wires.

Well, one possiblity is that one of the controller's phase outputs has
gotten stuck on or off.

Jon