Re: [CAD_CAM_EDM_DRO] Is it possible to change the BP motor to eliminate shifting?

Keith Clark wrote:

>Is it possible to change the 2 HP motor on my (Series 1 originally
>Boss controlled) Bridgeport spindle during conversion to control
>spindle speed, to a motor that could have the entire speed range
>needed and thus obviate the need for the gear shift?
>
>

Yup, you need a 100 Hp DC motor. The minimum speed on a 1J Bridgeport
is 80 RPM. To deliver 2 Hp at 80 RPM requires 50 times the torque at
4000 RPM. So, you need a motor that delivers 2 HP worth of torque at
80 RPM, but can also go up to 4000 RPM or so.

This is not very practical. That's why ALL machines with widely varying
speeds
use gears.

Jon