Have 110V 20A (not enough A) and unused 220V 50A. Options?

I have a shop run off of the one house panel I have. My Lathe is about 30' form the panel and runs off a 20A 110V circuit. I cannot use the higher speeds on my lathe without surging and eventually tripping the breaker (I've tried my two seperate 20A circuits and they both work the same). There used to be a ceramics kiln run off a 50A 220 circuit that is ideally suited for the lathe. Can I replace the 50A 220 breaker and use only one leg to run a 25A 110 circuit to the lathe? Or is there a better way to get more amperage to the lathe using the unused and now disconnected 220V 50A circuit?

 

That would depend on the wiring method. The old kiln was most likely straight 240 and did not have a neutral.

 

The wires are Red, White, Green, & Black. I assume it does have a neutral, ground, and two hot (though disconnected) wires?

 

You can switch the breaker to a single pole breaker connected to either the black or red. The white and ground will connect to the proper bus bar in the panel.

Depending on the acceptable wire sizes allowed on the breaker you may need to reduce it to fit. You will need to reduce for the receptacle end.

 

That would be a huge bonus for you if you did have a large cable with those four wires.
A neutral would allow you to install a 50 amp sub-panel which would give you many options for power.

Here we are allowed to connect a 60 amp sub-panel using #6 wire.
Do you know what gauge the wire is?

 

I am unsure what gauge the red, black, & white wires are though they are all the same gauge (they are 7 strand and measure from .200"-.296" diameter (depending on how the wire is oriented) for the wire and .310" with insulation, using my calipers). Here is a picture with a ruler for scale: http://i157.photobucket.com/albums/t...ps3ca93db9.jpg

 

.200 would be close to #4 but looking at them I would guess #6, 0.1620. I'd suggest either measure them with wire stripers or get a one foot length of THWN from the hardware store and compare the striped size.

 

Make sure the power is off and you may be able to straighten and pull out the wires in the box and look all around to see if you can see the printed wire type and size.
The other end of that wire in the breaker panel may have enough length and be in better shape to read the size......Just make sure the wire size in the panel carries on without dropping a size or two or doesn't branch off.

 

The OP may be able to read the size on the cable sheath near the panel.

 

Ya, that might work and limit exposure to volts!
Plus he should check as much of the cable as he can to make sure the cct doesn't branch off.