If it can be rewired, then 240V will be your better bet. Operating a 2 HP motor on 120V is an "iffy" proposition.
I agree. The rated starting current draw should be popping my 20-amp breaker routinely, but it isn't, even once when the motor stalled on start when I had the spindle belt too tight. That surprised me quite a lot, and I was really surprised (I think I mentioned it) when I saw that it was using 120 VAC back in Uncle's hanger. I need to run another circuit for 240 so I'm not having to roll stuff over the cord. The only other 240VAC rolling tool I have is a 3-HP cabinet saw--my other tools are 1 HP or less.
That should have been all that was needed.
It depends. The serial number card stated that the motor was to be supplied by the customer, but it also showed (in handwriting rather than typing) the operating characteristics of the motor used. As previously mentioned, the lathe was sold to Beth Steel to be used in the "Elec Sup" department of what was at the time the world's largest steel plant. 25-Hz power was (and still is) used by electric trains on a large portion of the Amtrak Northeast Corridor line, supplied at much higher voltages using overhead catenary. Amtrak sells a lot of that power to other users of that line, including SEPTA and NJ Transit. The Sparrows Point Shipyard where this lathe was first delivered is in Baltimore, near the southern end of that line, which extends down to Union Station in Washington DC. I do not know if Beth Steel shared power with the Pennsylvania Railroad (the original owner of that line; they were emulating the 11-KV, 25-Hz power used by the New York, New Haven and Hartford Railroad starting in 1908), but it's certainly possible. And it would mean transformers, motors and other power equipment wired for that frequency would be locally available. It's not impossible that Beth Steel generated power for the Penn, given that the Penn started using it in 1915 and the Sparrows Point plant started operation in 1887 under Maryland Steel (Bethlehem bought it in 1915, and it was one of their four Baltimore shipyards). The reason for using 25-Hz power was so that they could increase transmission voltages using the equipment of the day. They currently transmit power from substation to substation at 138KV.
This lathe was delivered in June of 1945, only a few weeks after the surrender of Nazi Germany and while WWII in the Pacific theater was still quite hot. Beth Steel was building liberty ships at Sparrows Point, and they continued to grow into the 50's, supplying steel for rebuilding and in response to post-war prosperity. Meaning: the plant was large and active for quite a while after this lathe was delivered.
So, for the "it depends". I don't know when Beth Steel liquidated this lathe, but I have to assume it was in the 60's or 70's, when the plant was shrinking rather than growing. It would have been outdated by that time, but I suspect it was used for as-needed repairs of other machinery in the plant, not for production (where it would have been considered too small and where being outdated would have been more of an issue). Of course, when they sold it, they would have had to convert it for use on the regular power grid in order to find a buyer, or the buyer would have done it after the purchase. I suspect both would have been counting pennies, and would have used the pulley that originally came with the lathe for use with a 1410-RPM motor. Normally, the pulley would be replaced to provide the specified speeds for the lathe. Appropriate pulleys are easy to make and easy to buy in whatever size would be needed. That tells me that it was probably the buyer that replaced the motor.
I have no idea if it was ever wired for 240.
There is a round three-phase power receptacle on the back of the base unit next to the switch-arm mounting, wired how and for what purpose I don't know.
I haven't messed with the wiring, but I need to go ahead and do that. Normally, I do that first as a matter of safety--I'm apparently more picky about wiring safety than previous owners of the stuff I've bought.
As for your tach, pictures, or "it didn't happen"!
Yeah, yeah, yeah.
I was squeezing it in between spousal assignments, and the holidays are over. Maybe I'll sneak out there tonight.
Rick "pic of the tach in the 'What did you buy today' thread" Denney