Buying a lathe blindfolded

$500 and a case of beer should be safe.

$500 is what I paid for my Clausing 6913.

i

The problem with a 10EE is the motor drive. There were two versions. One is a 3-phase motor spinning a huge DC generator. If you know a little about electric motors, you should be able to make this run. The later system used a bunch of vacuum tubes to drive thyratron tubes. These drives are a bit complicated. It would be possible to convert it to two SCR drives, one big one for armature, a small one for field, and use tach feedback to make rock steady speed settings. It may also be possible to keep the thyratron drive running, or retrofit it with SCRs.

Others have changed to direct drive by AC motor, but you lose some low-end torque this way. Monarch used a massively large motor so it could deliver nameplate HP down to very low speeds.

Other than the motor drive, the rest of the machine is battleship tough, so is not likely to have much wrong. It could have a lot of wear, though. Of course, if you can power it up and run the spindle, that eliminates problems in the spindle drive.

Jon

Holy smokes, that's scary. I am electrically challenged. V

With some effort, you can become less electrically challenged.

I would think that doing anything at all with this Monarch, would require some electrical expertise.

i

I won't even pretend I can give concrete advice on how to evaluate or price a Monarch. But I would suggest you go wiggle and turn anything that will wiggle and turn. You want to check for backlash in the crossfeed and compound, and any wiggle/slop in anything that rotates or slides. If you have a decent straight edge, take it and check the ways near the headstock with a feeler gauge, looking for wear. I'm not familiar with the Monarch so not sure what all to check. But finding stuff that's loose/sloppy is not a good sign if you can't budget a full rebuild.

Years ago I found an HLVH for what seemed like a decent price. Until I turned the crossfeed and discovered half a turn of backlash... if everything seems smooth and tight, from what I've read, your biggest fear is probably the spindle motor drive setup. There's a few guys there that have been all through that issue and can offer specifics.

Jon

...

Vernon, we're teaching Iggy to do a CNC control, that ain't easy. We can walk you right through a VFD install on the 10EE. I own one and bought it just 'cause I had to have it. Best purchase I ever made.

Make sure everything turns and slides. Damn near none of this ever breaks on a 10EE but be sure. Do plan on drive work - almost every old 10EE was slid into the corner because of this.

Karl

Given that the lathe hasnt been run for a very long time..that sounds like a very good and fair price.

Also given that it "probably" hasnt been run because the drive took a shit....my personal opinion matches the others. If its easy to fix..fix it. If not..simply remove the motor and controller and install a simple VFD and decent sized electric motor. Id personally use a 5-7.5 HP Wegg or similar brand electric motor.

Figure $500 for motor and drive. So a 10EE for a grand isnt a bad thing, assuming all else is in working conditon.

If you think you can get it for $500..and it sounds like its a good chance...a good check out of the other Stuff might be proper here and some 10EE owners might toss in the things to test and check.

Ive used some, but can only give generic suggestions of how and what to check for.

It IS one hell of a lathe and if you can score it...you will never be disappointed, Even with a bit of wear here and there.

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Installing a Variable Frequency Drive ( VFD ) is a piece of cake. Two wires plus ground for the input to the VFD and three wires plus ground from the VFD to the motor. And VFD's can be found at reasonable prices.

Dan

=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 Dan

Based on the following comment

"The problem with a 10EE is the motor drive. There were two versions. One is a 3-phase motor spinning a huge DC generator. If you know a little about electric motors, you should be able to make this run. The later system used a bunch of vacuum tubes to drive thyratron tubes. These drives are a bit complicated..."

I think I would rather have the former than the latter. I will try to get some information off the data plate and start there. Thanks to all!!! V

But the 10EE has a DC motor with an unusual frame. You would probably need a good-sized lathe to make the conversion parts to fit a standard AC motor.

Jon

The motor is a normal wound field DC motor, but the control uses field weakening to spin the motor above 2000 RPM. The field is full on from

0 to 2000 RPM as the armature supply ramps up. From 2000 to 4000 RPM the armature is full on, and reducing the field current increases the motor's speed.

I think you could use two SCR drives, one for the field and one for the armature, as long as you can control them as described above. The thyratron EEs have a 2 gang pot with a funky taper to control the two supplies.

Is the funny taper correct to command a pair of SCR drives? Or is it not sorted out into anything as easy as "current to coil"?

this would be an obvious use of a small computer, or alternatively as you suggest a primary SCR drive for the armature and a small one for the field - a lamp dimmer may well do for the field - then the user could know to adjust appropriately

If you buy it by the pound, you cannot possibly loose. There will definitely be someone ready to buy it from you for by-the-pound x 5 regardless of the shape.

I believe it would be possible. Unfortunately the pot is trouble prone and a replacement is rather expensive, something like $150 IIRC. I performed surgrey on mine and was able to repair it, but I've since sold the lathe.

OUCH!

Actually you could do this with a dual pot and either some diodes and op-amps, or a properly programmed itty bitty microprocessor. There's probably a way to do it with a PLC or similar, but I don't talk PLC.

Hey everybody... I'm now looking into a different lathe - also a Monarch. However, this one is a 16"CV model built in 1945. It has a

18.5" swing and 30" centers. I need to resolve two problems however in order to get my courage up enough to decide if I can swing it.

First, the weight. If a Monarch 10EE weighs 3200 lbs., this one must weigh quite a lot more. My forklift is rated at 4000# tops. I have been unable to find a weight for the thing but it looks like it might very well weigh 6000# or even 7000#.

The second thing that worries me is the drive motor. I was unable to reach the engine data plate and was unable to find any specifications on the web. However, if a 10EE has a 10HP motor it seems plausible that this lathe could have a 15HP motor. I imagine the motor is wired for 440v 3ph. I HOPE it could be re-wired for 220v 3ph. However, if the motor is indeed 15hp or bigger, I get the impression that this is the outer limit for single to 3 phase VFD boxes never mind that they cost about $1500. It's not so much the expense of the box that worries me as what happens if the motor CANNOT be rewired for 220v? And of course, if the VFD will barely output the needed power what will that do the life expectancy of the VFD? I surely wouldn't want to burn up more than one of them a week or it would get pricey!

I have really found very little information on the model 16CV lathe. Therefore, it concerns me that I could easily step off into something I cannot get over the finish line - never mind off the trailer... nevertheless, I'd love to have it and it looks like I could buy it pretty cheap.

Is there any reasonable doubt that the thing could be repowered with a smaller motor that would reliably run from a VFD? If I can get confident that it can be repowered I might consider hiring a machinery mover to get it into my building!

Any and all advice is gleefully appreciated. V

V

Hmm -- 1945? I think that is pretty likely to be the motor-generator type rather than the thyratron tube electronics type. Those came into being later.

Hmm ... running one form 240 VAC single phase at 15 HP would draw nearly 47 A neglecting motor efficiency. Can you feed that much current at 240 V to *anything* in your shop? (The current would be a bit less with a true three phase supply.)

:-)

Given the age, it probably has a three phase motor running a DC generator, and uses that to run the DC spindle motor. I don't know what voltages it produces form the generator, but you might be able to replace the motor-generator setup with a switching power supply which would reduce the total draw from the line, and perhaps give you some flexibility in selecting the voltage from which it runs. But if it is on the order of 15 HP -- expect to need to feed it a *lot* of current from 240 VAC.

Does your building have a thick enough slab to support that machine's weight?

Personally -- I think that you should stick with the 10EE. It is easier to move, and there have been a lot of conversions done and written up, so you won't need to design the conversion yourself, you can find several people who have done the conversion different ways, and read through them all to settle on one which looks to fit your capabilities and available equipment.

Good Luck, DoN.