X2 Motor is having issues and not running right.

[BrassBuilder]

I started to mill a part tonite. The end mill went about 2" along the length of the cut (approximately .020 cutting depth) and then the motor bogged down. I raised the spindle up so that the end mill was not touching anything and the motor kept getting slower and slower.

I took the motor off the mill and took the brushes out. There was still plenty left. I then took the end cap off of the motor and the end of the armature where the brushes ride against was really black. I took a scratch pad and cleaned the armature off until I had a bright copper color. Put it back together and the motor ran perfectly for about one pass around the part and then bogged down again.

Any suggestions on a possible fix?

What are some good options to replace this? LMS has the replacement motor for $179. That seems like a lot for what I am getting. Keling had some sort of motor/controller available, but I can't find it now. I think it was around $300.

Any other suggestions for a replacement motor?

This happened at the worst time. I had a bunch of parts that I wanted to cut this weekend. Now I won't have an excuse to get out of yard work.

UPDATE: I thought I had posted something about this before and about a year ago, I had the same issue. I didn't do anything with it then, but it worked great for the last year now.

X2 Motor Replacement

I'd still like advice on a replacement...just in case.

Thanks

Mike

[hoss2006]

The LMS motor is actually the same as the one from grizzly ($197)
http://www.grizzly.com/products/G8689/parts/1
You can also call Harbor Freight and order one for their X2 but it's likely a couple months for delivery.
Mini Mill - 2 Speed Mini Milling Machine
A treadmill motor is also a common replacement, read more here for the same one I used on the G0704.
Projects2
Hoss

[BrassBuilder]

Hey Hoss,
I got the bad news...my motor is shot. I guess there is a short in the windings somewhere. I took the motor to work today and our electric department put the armature on their test bench and cleaned up the end where the brushes ride against. I was able to watch them and they used about three or four pieces of equipment on it. One was called a graver....graner...something like that. Anyway, they gave it back to me and they weren't sure it was going to work. It doesn't. It will run on a very low speed but as soon as I turn the rpms up, the control overload shuts the motor down.

So...here is what I am looking at:

The Keling 1100w motor and controller. $500
Replacement motor from LMS. $200
This motor from Surplus Center. $40
Surplus Center - 3400 RPM 1 HP 120 VDC PM MOTOR

As a temporary fix, I was going to get an AC motor from the local hardware store and install that so I can get my parts cut.

I've been looking around on ebay for a treadmill motor, but I can't find anything that looks like it would work.

I also have a KBMM-225D controller that is just sitting here screaming to be used.

I'm leaning towards the Kelling, but I have no idea if they got that controller issue fixed. I see the new shipments have the improved controller.

Anyone have any experience with the Surplus Center motor?

Ugh...I was really looking forward on making some chips this weekend.

Thanks

Mike

[Al_The_Man]

I was able to watch them and they used about three or four pieces of equipment on it. One was called a graver....graner...something like that.
Mike

Growler, it detects shorted turns in armatures.
It treats the armature as the secondary of a transformer and the output is read from the comm bars, low output = shorted turn.
Al.

[BrassBuilder]

Growler, it detects shorted turns in armatures.
It treats the armature as the secondary of a transformer and the output is read from the comm bars, low output = shorted turn.
Al.

Yeah...growler...that was it! I was close though. LOL.

They also cleaned up the slots on the end of the armature using another tool. I had hopes that it was going to work...

Mike

[BrassBuilder]

Alrighty...

Got option 4 going right now. I have a treadmill motor here from my lathe, but I thought it was going to be way too big size wise and weight wise for the X2. I set it on top of the head and the little NEMA 23 motor raised it's new motor up and down like it wasn't even there. I'm getting the new mounts built right now. Since I don't have a running mill, the parts are getting cut with my bandsaw and drill press.

If it looks like the NEMA 23 is under strain, I have a NEMA 34 here that should do the trick.

The motor is 220v. I will use the previously mentioned KB controller on this and get rid of the last of the X2 electronics. Yay.

Pictures tomorrow once I see if this will actually work. It should.

The mill is getting Hossisized with bigger travel as soon as I get the parts I need and get my lathe conversion done.

Mike

[BrassBuilder]

Might have an issue....

The treadmill motor that I have has a label showing how to wire it CCW. I need to run this CW. Will that be an issue switching the wires around and running this CW in lieu of CCW?

Mike

[Al_The_Man]

Normally with a DC brushed you just reverse the DC power, but on some of these uni-directional motors the brushes are offset, making it more efficient in one direction, so it may be an issue?
If the stator did not carry the brush gear, you could swap the stator end for end
Al.

[BrassBuilder]

Normally with a DC brushed you just reverse the DC power, but on some of these uni-directional motors the brushes are offset, making it more efficient in one direction, so it may be an issue?
If the stator did not carry the brush gear, you could swap the stator end for end
Al.

I looked the motor over and I don't see anyway of reversing the stator. I did notice the brushes are sitting at an angle on the end of the armature. That has me concerned since I'm running the motor "backwards" from the way it was designed (CW instead of CCW).

I guess I am also not supposed to make any parts this weekend....

I got the motor hooked up. Seemed to do pretty good. And then the same thing happened with this one that happened to the original. Started bogging down and losing RPMs. After looking the situation over some more, I see my spindle bearings froze up now. They were probably the reason for the original motor going heywire. I got the bearings out and the bottom one is definately the bad one. The top one isn't too bad.

I have new bearings coming from McMaster and they are rated for 11,000 RPM.

While I am sure having a bad bearing didn't help the motor issue at all, I am still wondering about running it CW...guess I'll find out when I get the new bearings in.

I'm hoping I can get this treadmill motor working. I can already see a difference in power in the thing over the original motor. Running on 220v now with a KB motor controller.

[Al_The_Man]

While I am sure having a bad bearing didn't help the motor issue at all, I am still wondering about running it CW...guess I'll find out when I get the new bearings in.
.

You probably are not going to damage the motor, but your torque is going to be lower than it would be in the CCW direction.
Al.

[BrassBuilder]

You probably are not going to damage the motor, but your torque is going to be lower than it would be in the CCW direction.
Al.

And that shouldn't be an issue. I've never milled steel in the lathe. I had to mill a piece of cast iron once (and only once), but the rest is aluminum and brass.

I knew the bearings were getting a little rough, but was hoping they had enough life left in them to get four pieces kicked out. Hope I didn't burn up another motor in the process.

I've got my eye on a couple of treadmill motors on ebay. Crappy pics...lack of info...and the seller hasn't got back to me on whether they run CW or CCW.

Thanks

[Al_The_Man]

Unfortunately in recent years the Ebay price of large DC servo motors has seemed to soar, you could get them for a steal some years back, they make nice spindle motors though as they often come with a DC tach which can be connected to the SCR controllers.
Al.