Re: [CAD_CAM_EDM_DRO] Ametek DC motor info?

Couple of observations/questions.

So the lower voltage versions of these motors my be the more desirable
ones if they have lower resistance?

Isnt 2300 bucks a bit much for that Grizz 1126? Looks a whole bunch like
the HF gear head model.

Mark

Jon Elson wrote:

> Yup, there are thousands of these motors out there. I think they were
> used in the CDC "Keystone" tape drives. They work pretty well for
> mid-sized mill and similar CNC applications. They have too much
> resistance for heavier machines, such as the Series I Bridgeport.
> You can still use them, but unless you use a 72 V power supply, you
> can't get anywhere near peak current through them. If you start
> with the 4 Ohm or so motor resistance and then add a few Ohms
> for the driver, it takes up to 70 V to get 10 A flowing, and that is
> with the motor standing still. If you add the back EMF, it gets
> even worse.
>
> I have a client in town who has a machine like the Grizzley 1126
> (the geared-head mill) and it works pretty well using these motors.
> He only has a 36 V power supply now, and that limits the speed and
> torque a bit. But, it DOES work pretty well.
>
> For a plasma table, you'd want a pretty coarse leadscrew thread,
> or a larger pulley for belt drive. I think the motors are rated for
> 900 RPM at 40 V. You can get more speed at higher voltage without
> harming the motor.
>
> Jon