Baldor 2HP Shunt Field DC Motor CD6202
Baldor 1HP Shunt Field DC Motor CD5318
Baldor 1HP Permanent Magnet DC Motor CDP3460

(Click on images for a larger view)
So a few years back, 5 to be exact, I decided I would like variable speed on my Rong Fu RF-31 Mill. So I set out on a quest to find a 2HP DC Motor, checking surplus houses and also watching eBay for one. I really didn't want a permanent magnet one so I held out for one that had a shunt field and also be a Baldor but I figured that was a bit wishful. Have a pretty decent understanding of DC Motors and control of them, majored in Power Technology in college and worked in Engineering at Allen-Bradley Drives Division when they were small, nothing like they are today. If I wanted to I could design my own DC Drive to control these motors, but as affordable as they are now it's not worth it, probably cost more to do. Eventually I did find a motor and bought it, that was back in February 2007. When I got it I became concerned about its weight and size and started thinking maybe this isn't such a good idea. The motor weighs in at a hefty 90 some pounds and that's over twice the weight of the Marathon 2HP motor that is currently installed on the Mill. So the project fell by the wayside and the motor sat and collected dust.

Well I'm back on the project now and I'm going to do what I have to do to safely and sturdily mount this motor on the Mill.

So the first thing I decide needs to be done is to check out the motor, never had done that. So I'm thinking new brushes, maybe new bearings now and not later after it's installed, and might have to have the commutator cleaned up. After all I bought a used motor. So I contacted a few Baldor authorized service centers by email and finally called one to get an idea of the cost to do this. But was I surprised, way more then I thought it would be. And I really didn't know if the motor needed it so time to find that out. Below is what I found. Boy was I surprised!
  As you can see the commutator is in excellent condition, it does not look like it was run for any extended period of time at all.
  The brushes also show no real wear on them at all.
  And this thing is spotless inside, no dust dirt or grime as would be expected in a motor that was used.
  All I can say is man what a score, I had no clue what I had until recently. I might have checked it out in 2007 when I bought it, as I usually do, but I don't remember the deal being this sweet. And I thought I was buying a used motor and was expecting the worst. $139 for the motor, $65 for shipping and Baldor's 2012 list price is $2,379. The price was probably less in 2007, but still, and the fact the motor looks to be new and never used, what a plus.
Now the only thing I'm contemplating doing is finding a Tach mounting kit and Tach for it. I have a Tach but was planning on using it on the Baldor 1HP DC motor I just purchased for my lathe. Got a sweet deal on a new one of those, $293. Was up till 3AM trying to decide whether to buy it or not, wasn't looking for one but stumbled on it. I knew if I hem'd and haw'd too long it be gone. Maybe which ever machine gets its DC Motor first will get that Tach.

And I also already have the DC Drives to run these motor, picked them up way back too. Three Boston Gear Beta II Drives. All with accel, decel, jog, current limit, min speed, max speed, dynamic braking, etc. and two with forward/reverse.

I also think I'm going to motorize the crank for moving the headstock up and down, it's cumbersome now, with another 45lbs. added to it it's going to be worse. If the headstock is made somewhat balanced front to back this is definitely going to throw that balance off.
  And here's the new Baldor 1HP CDP3460 DC Motor I received on 01-May-2012. This thing is sweet lookin' isn't she? $293 and $24 shipping.
And another score. After 20 some pages of Google'n (no kidding) a bran spankin' new Baldor XPY Tach for $349. Shipping included. For one of the two motors above. Now I need the Tach Mounting Kit for both. Getting a deal on those does not look very good. After looking for a week or so, nothing yet.

And while I'm on this DC Motor kick, got a line on a 1/2HP DC motor for my Mini Woodworking Lathe.

Update (01-Dec-2013): Finally found a reasonably priced *new* TK3400 (Tachometer mounting Kit) on eBay last week and I am now the proud owner of it. Game on for getting the 1HP DC Motor on my 9x20. Oh and I did pick up that motor for my Mini Woodworking Lathe...

Update (05-Dec-2013): Found another brand new Baldor XPY 50V/1000RPM tach for $250. For the Mill. On the way...

Update (22-Mar-2021): Found another brand new Baldor CD5318 1HP Shunt Field DC Motor... Destined for my lathe...
  And here's a new Baldor 1HP CD5318 Shunt Field DC Motor I received on 25-Mar-2021. Another sweet lookin' thing, eh? $175 and $64 shipping.