On 2009-07-02, wrote:
On Jul 2, 5:22*am, "DoN. Nichols" wrote:

* * * * A DC motor, a Variac, and a rectifier would do a nice job there.
If you really care about spindle speed precision, a servo motor and
servo amplifier would be guilding the lilly. :-)


* * * * But a DC motor a Variac, and a rectifier would be more flexible,
giving you a much wider range of speeds, and the ability to change the
speed in mid cut without having to stop the motor and change the belts.

[...]


* * * * Enjoy,
* * * * * * * * DoN.

Start looking at Craigslist or Freecycle for a treadmill. Most of
them have a DC motor and controler, but I did find one with a AC motor
and a varible speed pulley.

Are you complaining about them mostly being DC motors, or about
the one AC and the VS pulley assembly? Both would be interesting to me
Or did you get one assuming a DC motor, and when you got it home you
discovered the VS pulley?

Look under Free and be patient.

Or look in Ebay for a small VFD and then locally for a small 3 phase
motor. I just got a 56 frame three phase motor for $5 at a garage
sale.

That would be a good way to go -- though I think that the DC
motor would do better at really low speeds.

Of course -- I'm not the one looking for the slow speed motor,
just one responding. :-)

Enjoy,
DoN.

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