I picked up an old Sheldon EXL 56P 10" lathe the other day. Previous owner
put a new Dayton 110/250 motor on it (that's whole nother story). Anyway, he
had it hooked up in his garage so I could run it. He had this plug on it
(250, 3 prong, twist lock) but the lathe was apparently wired for 110
(according to the add. I didn't get to speak with the owner directly).
http://waynef.smugmug.com/photos/68932303-M.jpg

The lathe has a fwd./rev. drum switch and ran fine in both fwd. and rev. in
his garage when I checked it.
Drum switch:
http://waynef.smugmug.com/photos/68932283-M.jpg

I got it home and wanted to stay with 110 as I have lots of 20amp 110
circuits in my shop. So I installed a 110/250 four prong twist lock
receptacle in one of the my two gang 110 duplex boxes on the wall where the
lathe will go:
http://waynef.smugmug.com/photos/68932299-M.jpg

Removed the three prong 250 plug he had on the lathe and replaced it with a
four prong plug that matched the new outlet:
http://waynef.smugmug.com/photos/68932277-M.jpg
Wired like this:
http://waynef.smugmug.com/photos/68932292-M.jpg

Plugged the lathe in and turned the drum switch to forward. The lathe
(chuck) ran in the counter clockwise direction. Switched the drum switch to
reverse and the lathe again ran in the counter clockwise direction.... huh.

What's up here? Does both the black and white at the receptacle need to be
hot for the fwd./rev. to work properly in this type of set-up? My 20 amp 110
outlets are all wired with the typical hot/neutral lash up.

If I really had to, I could run some flexible metal conduit along the wall
from a junction box that contains a hot 220 circuit and run the lathe on 220
I suppose, but I was just trying to take the path of least resistance.

Any help would be appreciated.