u/Pure_Imagination_300

I have recently downsized my mill from a J-head Bridgeport to a benchtop sized. With the loss of the knee meant I was sacrificing distance between the head and the table. I am using an R8 mounted #33 Jacobs chuck and without a bit it is about 2.5" - does anyone know of a 1/2" capacity drill chuck with a lower profile? Since most keyless chucks are longer than their keyed counterparts, I am fairly certain that it will need to be a keyed chuck.

I've even been considering an ER-32 in an R8 mount ... this is not as adaptable as a drill chuck, and changing sizes would be slow, but it's worth considering if there is nothing else out there.

Thanks in advance

Sorry for the long first post in this group - but here goes:

I used to have a milling machine, a metal lathe, and a surface grinder. They all ran on 3 phase power. I got rid of the surface grinder couple years ago. I powered them all using a rotary phase converter with a 2hp motor suppling the 3rd phase. I sold the mill and let the buyer have the phase converter to close the deal.

I replaced the phase converter with a Digital Phase Shifter and now my motor is getting hot ... like more than 200 degrees if I am not careful and take breaks after every couple passes.

The digital phase converter (hereafter called the 'DPS) is marked as follows:

Model CPS 5hp, Range 4-5 hp, Amps 15

The motor is marked as follows: (there is no 'Catalog No' on the plate)

Baldor Reliance Super E, 3 phase / 2 speed, 05E050X121G1, HP 2 / .5, Amps 6.1 / 2.6, 145T Frame, Des B, Class F

I'm not sure what the hp designation of "2 / .5" means

My votages across the DPS may be my problem, but I'm not sure why it's happening.

I have a red and a black for my line in. Metering across them is 244 volts both when the motor is running and when it's not running.

The output of the DPS has three lugs, the wires are black, red, and the 3rd is marked with tape to make it orange.

When the motor is not running:

Black to Red - 244 volts

Black to Orange - 244 volts

Red to Orange - 0 volts

When the motor is running in a no-load condition:

Black to Red - 326 volts

Black to Orange - 242 volts

Red to Orange - 287 volts

I'm pretty sure the mis-matched voltages are causing the problem but I'm not sure why it's happening. Is the DPS too large for the motor and that's it? Or is a DPS not a viable solution for 3ph in a single ph basement? Do I need to get smaller DPS, a VFD? Or break down and get another rotary phase converter.

Thanks in advance to anyone that may have an idea of what's going on.

Charlie