1943 Monarch 10EE S/N 17646-Retrofit and Repair

A pic is worth a 1000 words. I mounted a 5hp 1750 motor INSIDE the old 3hp DC motor. There a chain coupling where the old DC shaft was cut. i put the speed pot on the same speed control linkage, same with the forward off reverse swtiches. can not tell form the out side it has a rebuild. FWIW, I've run this machine up to 4500 RPM many times - a bit more than most say is safe for a 1750 motor10EE a.jpg10EE speed pot F R switches.jpg10EE speed pot F R switches.jpg10EE drive.jpg
 
A pic is worth a 1000 words. I mounted a 5hp 1750 motor INSIDE the old 3hp DC motor. There a chain coupling where the old DC shaft was cut. i put the speed pot on the same speed control linkage, same with the forward off reverse swtiches. can not tell form the out side it has a rebuild. FWIW, I've run this machine up to 4500 RPM many times - a bit more than most say is safe for a 1750 motor
Thank you Karl,
very nice job! that was a very ingenious way to skin the cat!
i don't have the same DC motor in mine to copy the idea like you have it.
i do have a spare gearbox like you have pictured, but i may have to make/find an input shaft and then couple it to the motor.
i'd like to have a full function machine, but i doubt i will ever turn it to 4000 rpm
 
Very nice machine and what a score. As Karl and others have mentioned, a lot of information and very knowledgeable folks in some of the other forums, like PM. I have seen a number of 10EE discussions on motor/VFD replacement in different postings, in this case since all the control systems are removed, a VFD is the way to go. If using a single speed motor, what other have indicated is you need at least 7.5Hp and possible 10Hp; with the back gear, then 5Hp works well. If you have/use the back gear, then there is information/postings on different ways of mating it to a new motor. I like what Karl did, haven't seen that one before. You might look for an inverter motor, the one below will go to 6000 RPM. A couple of months ago I saw a Marathon BlackMax 5Hp going for $150, it was a steal. You may be able to work on different shippers to get the cost down, these motors are heavy. Otherwise a standard inverter (VFD) rated 1750 RPM motor would max out at around 2700RPM (90Hz). A flange mount may be more ideal if you are going to make some interface plate between the motor and gearbox.

https://www.ebay.com/itm/Baldor-Rel...P-230-460V-1760RPM-3PH-IDNM3665T/182487935288
https://www.ebay.com/itm/M3665T-Bal...-TEFC-230-460-volt-3-phase-motor/152731002102

 
..., but i doubt i will ever turn it to 4000 rpm

Needed 4500 RPM just yesterday. Have you ever seen a torx socket head screw with the little pin in the middle to prevent tampering? Well, I have a UPS power supply I'm adding more battery time to and needed this special torrx screw driver. These screw drivers have a hardened tip. So I mounted it in a collet and used a 1/16 carbide endmill to bore a tiny hole. Just try that in a lesser machine.
 
Very nice machine and what a score. As Karl and others have mentioned, a lot of information and very knowledgeable folks in some of the other forums, like PM. I have seen a number of 10EE discussions on motor/VFD replacement in different postings, in this case since all the control systems are removed, a VFD is the way to go. If using a single speed motor, what other have indicated is you need at least 7.5Hp and possible 10Hp; with the back gear, then 5Hp works well. If you have/use the back gear, then there is information/postings on different ways of mating it to a new motor. I like what Karl did, haven't seen that one before. You might look for an inverter motor, the one below will go to 6000 RPM. A couple of months ago I saw a Marathon BlackMax 5Hp going for $150, it was a steal. You may be able to work on different shippers to get the cost down, these motors are heavy. Otherwise a standard inverter (VFD) rated 1750 RPM motor would max out at around 2700RPM (90Hz). A flange mount may be more ideal if you are going to make some interface plate between the motor and gearbox.

https://www.ebay.com/itm/Baldor-Rel...P-230-460V-1760RPM-3PH-IDNM3665T/182487935288
https://www.ebay.com/itm/M3665T-Bal...-TEFC-230-460-volt-3-phase-motor/152731002102


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Thank you very much for the kind words and thank you for the additional information.
is the video of your creation?
the lathe sounds silky smooth!
 
No not my video, I had looked into the VFD conversion and the different factory drives for the 10EE in another forum. Kind of fascinating the drive technology and how well it worked back in the day. There are a lot of discussions as to keeping the factory drives vs. VFD conversion, but now that the tubes for the original drives are very scarce an expensive, other options are more attractive. A VFD conversion if done correctly, can be a very suitable alternative drive and keep these going. It is apparent that it is best to maintain the gear reduction drive for low speeds, otherwise you need a much larger drive motor. Probably optimal to go with an inverter/vector motor that can spin up to 6000 RPM, you can then do the final belt ratio to achieve the top end speed you are looking for, assume this would be around 4500 RPM. If you need any help with the VFD end let me know. Cool project, look forward to getting the beast up and running.
 
Hi MKSJ,
thank you very much for the input.
i'm sure i'll be asking questions as the conversion goes on! :grin:
 
I talked with @mksj and decided to got with an inverter rated motor to gain the most from my retrofit-
Thank you Mark for the suggestions and help!

after hunting ebay i was able to find a Brand New Westinghouse/Teco Max-PE 5 HP, 184T Frame,1745 RPM, 111#lb inverter motor for the retrofit
for less than $400.00 shipped :grin:

FullSizeRender_8.jpg

and the serial plate for those interested,

FullSizeRender_1_8.jpg

now that i have the power plant and the VFD,
i can start my plans on coupling the motor to the newer style gear box and mounting the gearbox.

plenty more to come!
 
NICE MOTOR!

I routinely spin 1725 motors up to 4000. My thinking, they are built the same as 3500 inside and any made in USA item has 15% design room. So, how fast can you spin this one? The 10EE is built to easily take 5000 for short runs. I'm thinking work backward to get your pulley sizes.

I assume you are keeping the back gear??

You do know you need to trade in one of your other lathes so you can afford a 2J collet system. And then trade in another to get an Accurite DRO with their best scales. You won't be using them anyway after the 10EE runs.
 
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