10EE backgear mounting 3 phase motor

ITS BREATHING!!!!!!!!!!!!!!!!!

Spent the day assembling the motor and backgear. Then putting it in place. Just like putting 2 lbs. of stuff in a 1 lb. box. Had to trim one of the feet and turn the 2" x 3/4" bolts down to 1.5". couldn't find the correct junction box, had to clobber a bit here. Powered it at 6:15 (past my quit time), of course it runs backwards, but IT RUNS. Just need to switch two wires. Got lots of cleanup to do -tighten bolts,
adjust belt tension, re-install brake resistor, adjust backgear transmission link, yada yada.

Pic of the motor moving in and in place.




10EE moving in.jpg



10EE running.jpg
 
OK, like any project, now i know how to do it better.

First, I'd rotate the motor mounts a bit CCW to get the electrical connection near the top on the motor. Got to be careful to not interfere with other holes. Did not look careful but likely 15 - 20 degrees. See green in pic.

This allows the sides of the motor mount plates mount to be right up to the motor sides. Now trim the front transfer plate to be just bigger than the motor and backgear, I'd leave it a rectangle. just easier that way. See red lines in pic.

Now drill and tap the sides of the front transfer plate for the motor mounting plate attachment. See orange hole tap points.

The motor mount plates would be a large angle iron at the base with a plate welded to reach the tapped hole on the side of the transfer plate. I'd slot both the base and the sides at the attachment points. Allows vertical and horizontal adjustment.

The unit I built is tippy forward. Had to be because one of the base plate mounts in the lathe was in the way. Extend the side plate angle iron forward of the transfer plate to solve this.

Now the motor will not fit the orginal mounts so you have to pull this huge base plate to and drill and tap new locations. Now that pesky rubber mount won't be in your way to slide the unit in.

side plate design 2.jpg
 
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Had the lathe up to 3000 RPM yesterday... It just purrs and does the job.

Like I said in post 1, this is the best possible design to use a backgear. The running machine confirms this. Downside is finding a motor with a long shaft, needs to be 3.5" out with this design. It would be a plus to find one with a 1.25" shaft also. Not sure that's possible in 5 hp motors. I would not go smaller, 3 phase has less low end torque than DC.

Still this is a lot of labor to fabricate. My second 10EE rebuild used a 10hp motor and no backgear. Personally, I'd recommend this route unless you need to turn threads on something like 2" diameter Acme.
 
I personally think the extra effort would be worth it to keep the back gear. I want to be able to turn 3" acme threads if it came up.

You did a great job on this. If I decide to ditch the MG setup, this is the route I will take now that I've seen what you've done here. So much simpler than all the other setups.

I converted my MG unit to single phase, and it works, but ended up taking more time and effort than what you've done here, and I still have 74 year old electrical....

Thanks for posting this.
 
If you happen to know somebody in North East Minnesota, I'd suggest you buy the same offer I did on eBay. Long shaft motors at a discount are common as hen's teeth. I know shipping north of the border is prohibitive.
 
I have a shipping location right at the border on the US side. So that's not an issue. Its a 45 minute drive from my house.
 
Great thread. Wish I'd seen it sooner, because they are out of stock on those motors.
 
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