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Gearbox power feed


Jul 17, 2023
I have a 1965 step pulley with a gearbox power feed. I am looking for the motor rotation direction so that I can wire it correctly and not break anything. Any other information on these would be greatly appreciated.
Wiring the gearbox or the spindle motor?

Either way, it is somewhat going to depend on your local power source
Aren't both functions reversible?
The spindle motor is.
Is the gearbox reverse through gear shifting?
Is there a neutral position?
(My mill has a gearbox, but it is a SB and it does not break anything if accidentally wired in reverse. It just means the controls work backwards)
Good for you for checking, but i still think that dependent on how your 3ph feed is wired separate from the machine is going to be the factor. So figure out how to take the load off the gears if it seems to be a factor, wire it, and check.

If you wire it and the motor runs opposite the switch indication, just swap any 2 wires.

If you are using an RPC or (horrors) simple capacitor bank, the generated line sometimes works better if it does not include the line to the control voltage (to the magnetic coil assuming you have a magnetic starter). IOW take control voltage off the hot that runs through from the 1ph panel.

One beauty of 3ph is how darn simple it is. :)

Last edited:

Dan from Oakland

Sep 15, 2005
Oakland, CA
If you move the feed lever to the right, the table should go that direction. If not, the motor is running backwards.
Those old PFs are pretty simple, what am I missing????