- Joined
- Dec 13, 2016
- Messages
- 164
Like many, I have experienced M/G issues and was helped by Cal (10EE Whisperer) and narrowed the issue down to the rheostat. Searching high and low, I could not find any so I made the decision to convert to AC and VFD.
I researched and found many great ideas and a member of the Hobby Machinist group (Deek) (https://www.hobby-machinist.com/threads/10ee-vfd-conversion.64230/ ) has done a beautiful job with his conversion. He listed the primary parts he used and I filled in the gaps from there.
I went with a Marathon Blue Max 5 hp 3ph motor (found on e-bay) and kept the back gear. The joining between the back gear adapter plate and the motor is a pump housing (from Nebraska Surplus) that bolted up to the C-face of the motor. The adapter was where I was a bit nervous to be honest because everything had to be spot on. I used 1 inch thick 6061 aluminum plate for the adapter and installed a support bearing and seal for the through shaft using a lovejoy coupler to connect the motor shaft to the new shaft for the back gear. I had to make a new shaft from one end of the lovejoy coupler to the back gear assembly.
For the electronics, I used the Hitachi WJ200-075LF VFD, a 10 ohm 3 turn potentiometer 40 ohm 400 watt braking resister, new lighted start and stop switches, 40 amp WEG contractor with overload and circuit breaker protection. Programming the VFD was made simple by MKSJ's post he share wtih Karl_T's conversion using the same VFD (https://www.hobby-machinist.com/threads/monarch-10ee-rebuild-10hp-vfd-no-backgear.92017/page-2 ) (See post 15). The use of the contractor provides safety in the event of a power loss while running the lathe and power comes back on, the lathe will not restart. I also used a terminal block for the control wiring so I can disassemble this easier if need be. I made a panel and mounted and wired everything up and installed in the Tailstock end of the lathe. The vertical plate is welded to a bottom plate in a T fashion for stability. I used the original MG front motor mount bolt holes to secure the base and drilled and tapped the webbing in the top right and left corners and secured the vertical part of the panel there. I also used heat shrink labeling to label the wires. The printer is a Brady M210. Works great.
I retained the use of the original Speed control knob adapted the potentiometer to the gear and chain assembly using an adapter and set screw method. Each end was drilled and reamed to fit the respective shafts. I also retained the original forward and reverse switch and wired the drum switch to the VFD along with the potentiometer.
Getting the motor installed in the lathe required 1-1/4 spacers to raise the motor and bolted to the original motor plate (may vary with your application). The motor then bolted to the spacers. Of course all this done ensuring the alignment was right and back gear linkage considered. The belt needed to be longer and I decided on 91 inch belts. This also meant the shift linkage needed to be a little longer so I made a new one.
The lathe runs smooth and quiet. Surface finish has not been sacrificed from what I have seen on aluminum, 1018, 4140 and brass. Backgear works good and I have done some test threading with no issues.
Of course there are a lot of details not mentioned but I’m a visual person so the more pictures the better. How you make the parts is up to your discretion, skill and available tooling.
Researching and reading a lot. Staring at the machine for best options and ideas took some time. Got the electronics ordered and delivered and set everything up on the bench with the motor to get the wiring figured out. Once that was done I programmed the VFD and thank you to all the other posts for sharing links and files to settings for this specific VFD. This helped me out a lot!
Cleaned out the belly of the lathe was a nasty job but somebody had to do it and the wife and kids refused. Go figure.
I worked on this on the weekends around family responsibilities which meant an hour here and an hour there. I did manage to machine the back gear adapter plate in one weekend. I then decided to take a week off of work and get this done or it would draw out for who knows how long. But this week I got it done. Things that slowed the process down we’re labeling the wires but we’ll worth it and research. Electrical parts are in short supply so I had to search around for distributors with inventory.
Hope this helps others out should they decide to make the conversion. I was sad to see the M/G come out. I really wanted to keep the lathe as intact to its original design as I could but parts become an issue.
I do want to give a special thank you to Cal for working with me on the troubleshooting. This took a lot of time from his schedule. Emails, texts, phone calls, pictures and videos shared equates to a lot of time invested. So thank you Cal for you assistance.
I am in the Fredericksburg, VA and if anyone wants any of the parts I took out shown in the first picture, they are free for the taking.
Sent from my iPhone using Tapatalk
I researched and found many great ideas and a member of the Hobby Machinist group (Deek) (https://www.hobby-machinist.com/threads/10ee-vfd-conversion.64230/ ) has done a beautiful job with his conversion. He listed the primary parts he used and I filled in the gaps from there.
I went with a Marathon Blue Max 5 hp 3ph motor (found on e-bay) and kept the back gear. The joining between the back gear adapter plate and the motor is a pump housing (from Nebraska Surplus) that bolted up to the C-face of the motor. The adapter was where I was a bit nervous to be honest because everything had to be spot on. I used 1 inch thick 6061 aluminum plate for the adapter and installed a support bearing and seal for the through shaft using a lovejoy coupler to connect the motor shaft to the new shaft for the back gear. I had to make a new shaft from one end of the lovejoy coupler to the back gear assembly.
For the electronics, I used the Hitachi WJ200-075LF VFD, a 10 ohm 3 turn potentiometer 40 ohm 400 watt braking resister, new lighted start and stop switches, 40 amp WEG contractor with overload and circuit breaker protection. Programming the VFD was made simple by MKSJ's post he share wtih Karl_T's conversion using the same VFD (https://www.hobby-machinist.com/threads/monarch-10ee-rebuild-10hp-vfd-no-backgear.92017/page-2 ) (See post 15). The use of the contractor provides safety in the event of a power loss while running the lathe and power comes back on, the lathe will not restart. I also used a terminal block for the control wiring so I can disassemble this easier if need be. I made a panel and mounted and wired everything up and installed in the Tailstock end of the lathe. The vertical plate is welded to a bottom plate in a T fashion for stability. I used the original MG front motor mount bolt holes to secure the base and drilled and tapped the webbing in the top right and left corners and secured the vertical part of the panel there. I also used heat shrink labeling to label the wires. The printer is a Brady M210. Works great.
I retained the use of the original Speed control knob adapted the potentiometer to the gear and chain assembly using an adapter and set screw method. Each end was drilled and reamed to fit the respective shafts. I also retained the original forward and reverse switch and wired the drum switch to the VFD along with the potentiometer.
Getting the motor installed in the lathe required 1-1/4 spacers to raise the motor and bolted to the original motor plate (may vary with your application). The motor then bolted to the spacers. Of course all this done ensuring the alignment was right and back gear linkage considered. The belt needed to be longer and I decided on 91 inch belts. This also meant the shift linkage needed to be a little longer so I made a new one.
The lathe runs smooth and quiet. Surface finish has not been sacrificed from what I have seen on aluminum, 1018, 4140 and brass. Backgear works good and I have done some test threading with no issues.
Of course there are a lot of details not mentioned but I’m a visual person so the more pictures the better. How you make the parts is up to your discretion, skill and available tooling.
Researching and reading a lot. Staring at the machine for best options and ideas took some time. Got the electronics ordered and delivered and set everything up on the bench with the motor to get the wiring figured out. Once that was done I programmed the VFD and thank you to all the other posts for sharing links and files to settings for this specific VFD. This helped me out a lot!
Cleaned out the belly of the lathe was a nasty job but somebody had to do it and the wife and kids refused. Go figure.
I worked on this on the weekends around family responsibilities which meant an hour here and an hour there. I did manage to machine the back gear adapter plate in one weekend. I then decided to take a week off of work and get this done or it would draw out for who knows how long. But this week I got it done. Things that slowed the process down we’re labeling the wires but we’ll worth it and research. Electrical parts are in short supply so I had to search around for distributors with inventory.
Hope this helps others out should they decide to make the conversion. I was sad to see the M/G come out. I really wanted to keep the lathe as intact to its original design as I could but parts become an issue.
I do want to give a special thank you to Cal for working with me on the troubleshooting. This took a lot of time from his schedule. Emails, texts, phone calls, pictures and videos shared equates to a lot of time invested. So thank you Cal for you assistance.
I am in the Fredericksburg, VA and if anyone wants any of the parts I took out shown in the first picture, they are free for the taking.
Sent from my iPhone using Tapatalk
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