Hmmm..........That one appears to be a very early EE.
It would be interesting to call the Monarch works and ask them to look it up by serial number in the records.
It may be early enough to have originally had the 'Sundstrand' drive system, or it may have had one of the first iterations of the 'Ward-Leonard' system, with a Reliance DC variable speed motor, driven by the 'motor-generator', in which the motor end runs on 3 phase 220 or 440 VAC, the 'generator' end provides the DC power for the motor, and speed control is done by a vary large duplex rheostat.
It may be identified by several details as being too early for the vacuum-tube drive system.
Actually, your best option, once the particular version of your machine has been identified, is to locate and rebuild an original Ward Leonard system, from an EE which is otherwise unrepairable due to rust or damage. A surprisingly large number of these early EE models may be found in 'sabotaged' condition, from which parts could be salvaged.
One might easily think 'why should I find parts and recondition an obsolete system?', and that is a fair question.
The basic answer is that the Ward Leonard system works well, and will maintain spindle speed under varying load conditions. It has the disadvantage of noisy operation, with the whine if its original 3450 rpm M/G set. (fortunately, the M/G set can be re-located remotely, in an acoustical enclosure, which merely involves running conduit, and carefully tagging the wires at both ends before running the longer wiring)
The quiet vacuum-tube drives are tricky and troublesome. They ran very nicely when new, but after decades of component 'degradation', may require some sophisticated inspection and component renewal. If......and this is the big 'if'......the maze of electronic components are 'restored to as-new condition', a not-easy task for those who are not electrical engineers, they will run well and give good service for many years.
So-called 'modern solid state systems' are a gamble, from the stories one may read.
I've seen some EE lathes which were offered for sale with such replacement drives, after the owners had sunk a lot of $$$$$ in the drive system, and the drive would not adequately 'compensate' to maintain a steady speed under the variable loadings in a cut.
There are now, or so I've read, 'modern' systems which will compensate adequately, but are quite sophisticated, and quite expensive in first-cost.
This is probably one of the best available examples of the 'investigate before you invest' concept. Too many salesmen will tell you that their drive system will work for the drive loadings the EE will experience in operation.......and you'll find out differently.
I tried to run an EE which had been re-fitted with a Sabina drive, (and was offered for sale cheaply) which ran ever so smoothly, full range, under no-load or light load. When I tried a fairly heavy cut, well within the capability of a Ward Leonard EE, the Sabina system 'hunted' enough to cause quite a dramatic resonance on the tool/workpiece.......and this after a lot of time had been put into 'tuning' the system.
If you might be wondering, I've carefully kept my own 'module drive' vacuum-tube EE 'as original', with component replacement and 'tuning' as needed......but I will admit that I've 'gotten lucky', with some help from a old-time electrical engineer friend.
The story of the EE drive systems, and their world of problems, has been written-up quite extensively in the 'Monarch' area of
www.practicalmachinist.com
Do have a very careful read, there are a lot of stories, and second-hand experience is.....as is ever so obvious....the most cost-effective.
All that said.......if you need close tolerances for diameter and roundness, with a high finish, particularly in tough materials, the EE.....or the Hendey 'gagemakers' lathe'......will pay for itself surprisingly quickly, as compared to, say, the accurate but much more delicate HLVH model Hardinge.
There is good reason that many turners will make the investment for an EE or a Hendey gage lathe.....and you really have to run them awhile to understand the 'why' of those machines.
Added on edit.........would you be willing to post the serial number of your EE, and its date of mfg. from the data plate? I'm guessing the s/n is below 11000.....or not much above.
Oh, and a bit more edit.......your machine doesn't have the so-called 'electric lead screw reverse', which is actually a closely adjustable spindle motor stop, done by a micro-switch.
Some of the early EE machines did have the lead screw reverse like the larger Monarchs, along with an electric spindle motor stop, but yours doesn't have that system. Someone has apparently added the version of the bed stop housing from one of those, which originally had the L/R switch.
Indeed, a few EE users like that system, but most I've spoken with don't use it, as fitting a Trava-Dial to read longitudinal will do as well for running internal 'blind hole' threads, in practice.
Getting the stop set for the electric spindle stop is 'fiddly' and only really worth-while for short production runs with a dead-length collet. My own EE has that system, and I've never had reason to use it, but I do strongly recommend fitting a Trava-Dial.
cheers
Carla
I also know that the motor can only move up at the belt area, not down or side to side. So if the motor moves, the belt will slip. If it slips too much, I'll address it.
ics... here are the belts. 83" and 32". Application on the 32 inch belt is a Mazda RX-8 accessory belt. I would have used flat power belts and alligator lacing, but these were way cheaper and work well. On heavy cuts the belt slips on the motor shaft as you would expect.
