A very basic look at the 3 phase Motor driven Generator and vacuum tube rectified direct current variable speed spindle drives on the Monarch 10ee precision lathes.
I use and maintain two motor generator EE at work. I really like those machines. The motor generators have been taken out of the lathes and put in us in a tool room next-door. So our lathes are so quiet
Kudos dee dee. My first lesson on the 10ee is certainly welcome. No other, to my knowledge, has instructed at all clearly about the system of the dbl e like you have. Thankyou.
Excellent video! I don't think this has ever been done in such detail before. Great reference video! When I got my 1953 MG machine many years ago, it was before 10EE Lathes were 'cool' and there was this bit of a cult following of today. After watching the Monarch "Turning Point" video, and these videos by DD, I feel honored to have such a piece of precision engineered Americana from back in the day. It's highly probable my machine made parts that were part of the moon missions. Maybe some of the parts that were made on my machine actually made it to the moon surface. Mind boggling.
I was allowed to use the most worn out one at a company in the late 1970s, and never thought I would be able to own one. I remember them starting to hit the market in the 1990s at prices up to $8000, and a low point in around 2008 when many Gov rebuilt ones with Sabina drives sold at an auction for $500. I would like to restore the early tube drive next if I get a chance. Thanks!
Buying a 10EE scares me more and more when I think about all the electrical troubleshooting that comes with one but on the other hand, it has got to be challenging and rewarding.
I really am enjoying your channel. My 10ee has long been converted to a vfd with an adaptor for the back gear. It works well for me, because I use it as a hobby lathe. The 2hp Baldor that drives my spindle has plenty of power for me and I have never come close to stalling it. That said, I really wish it was original. My 10ee had a MG like your roughing lathe and must have had problems and remained unused because it has very little if any wear that I can detect. The only thing I'm fighting with it is the shifting lever on the back gear. I can adjust it so it works well in open belt or back gear, but not so that you can reliably go between the two options with the shifting lever without having to make an adjustment. Maybe I will get lucky and find the sweet spot where it works for both positions. Thanks for your wealth of information.
Hi dee dee! Very good explanation on the 10EE! I have an all original Tube driven 10EE myself and it’s great to get your insights on it. It would be great to have a live chat with you as I have lots of questions to ask and ideas to share
Great video, Dee Dee. This explains a lot. My 43 10ee only goes up to about 750 800rpm. After that, the field weakening doesn't come on and the lathe sounds like it's running away. Hopefully I can resolve the issue with the help of your video. Thanks
Hi! I have seen problems at that RPM, if spindle seems to surge the exciter voltage could be low from brush contact or the volt resister on the bottom of the exciter is set low.
You’re an incredible source of very interesting information, thanks for sharing it!! Are parts still available for the older drives on these lathes? If so, are they prohibitively expensive?
The factory has many parts for reasonable prices for the older drives. The motor generator units will have to be rebuilt by electric motor shops, but Monarch has the brushes and small things.
Outside of variable speed applications, what is the advantage of DC motors over AC motors? I ask because a non profit I am a member/volunteer at has a large Cincinnati Bickford radial drill press. There's a rectifier/power supply that takes 480 volts 3 phase and outputs 250 (approx) volts DC to power the motor and the column brake.
There is a similar set up at the ball mill I visited, there they apparently used it for the variable speed, on a geared head big drill the purpose may have been dynamic braking or the machine could have been on a ship with DC power available.
I have only seen photos of the older machines like that, the newer design is tricky also usually a worn key in the operating rod or one of multiple adjustments, just gave me an idea for a video, thanks!
I have a mid 60’s 10ee that is pretty much all original. The only problem is that the fan will stop running after about 2 hours use. Shut down and come back later and the cooling fan will run for a while again. Any thoughts on what the problem is?
The fan comes on with the filament transformers and work light with the disconnect switch on the right-hand door, the problem would be the fan itself and not an uncommon problem, that needs to be fixed right away because after using the machine and the control turned off, it is good to let the fan run awhile to cool the tube board down.
@@deedeeindustrialsuperprecision Thanks so much for responding to my question. I became concerned about the high cost and availability of the tubes and replaced them with the SCR's from Scissio Controls. Currently I have 3 useable tubes. But back on the fan, can you give me just a little more on what goes wrong with the fan? Is the repair straight forward or is it something made out of unobtainium?
Can you comment on people that convert the EE drive to 3 phase motors ( with VFD controller) and adapting to the existing back gear box. Is this a reasonable alternative? It would be nice to have you comment on one or you videos. Thanks
It is the only reasonable alternate drive that has been shouted over by idiots pushing solid state DC drives. The invertor conversions requires the motor mounted gear box to be adapted to an inverter rated 5 hp 3 phase AC motor. It has been working reasonably well for others. The factory last I know is using a 7 1/2hp inverter requiring 3 phase power.
@@deedeeindustrialsuperprecision So it sound like the VFD option requires a lot more horsepower to equal to the DC Drive. Thanks for the great insight and education for the drives on these machines.
@@skipdavison7682 Yes, when Monarch first went with AC drive, they tried a 10hp without back gear box it made threading harder because of less effective spindle braking when the half nuts are left engaged, the 7 1/2hp motor with back gear box got the machine in good operating almost as good as the DC drives.
