Re: [CAD_CAM_EDM_DRO] BP series 1

Joe Vicars wrote:

> I am looking at a Series 1 (boss 3,4,5) Bridgeport/Textron mill. I
> think I can get it for about 2000. Is that worth it?

Depends on the condition of the ways, ballscrews and spindle
bearings. If you can hear it run, listen to the spindle bearings.
If they are noisy, you are looking at $700+ for a set of ABEC 7
bearings.

> It has the rigid
> head, ballscrews, short table. The motors are the big heavy ones with
> fins.
> It comes with a quick change spindle and about 25 toolholders (they
> look like small 30 taper, no drawbar). Spindle speed and brake look air
> controlled. Spindle motor is 220/ 3phase.
> Are they stepper motors?

Yes.

> Will they work with a bipolar drive?

Yes, that should be no problem. If the motors have 4 wires, they are already
that way.

> Can
> I easily sever the spindle motor and speed from the control?

That should be easy. Spindle motor just has a contactor to 3 Phase power.
Speed control has an air motor to move the speed control. You could put
it back to original Bridgeport manual control, or use the air valves to
control speed from the new control.

> What voltage/current should I run the motors?

Depends on the motors.

> Can I use the existing power supply somehow?

Yes, but they have some odd features, namely a variable reactor to control
idling current by reducing voltage.

Jon