# Help Refurbish My New Mill.



## joe_m (Sep 2, 2012)

I'm spinning this question off from my "new mill" thread because I have a feeling it is going to take on a life of its own. Some of you suggested the big blue cannister was the original 3-phase motor so I did some research and I think you're right, but if it was there is no way to bring it back to life - all wires are gone and there is no nameplate to be found. Here's the setup as is. Based on the setup, and the mounting, where can I find a motor that will fit the original slot correctly? 3-phase is fine, it will run through a VFD. 


220V Power comes in from the wall to the gray box on the side of the mill. All that's inside is this little hookup. The white wires take voltage off one leg to power a 110V light. The two red go up through the metal conduit to the box on the side of the blue cannister (aka the original motor.)


The box on the side of the blue cannister is just a reverse switch. No wires go from it to inside the blue. They just go back to the 1-phase 220V motor that has been mounted on the back. That motor was mounted on a swinging bracket that has been welded to the back of the blue cannister.



There are 5 steps on the pulley below the blue cannister, but the original speed diagram shows 10 possibilities - a high and a low.


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## joe_m (Sep 2, 2012)

The add-an-image button was getting wonky so I had to split my post.

Here's the shot of the bracket welded to the back of the blue cannister for the new motor.


The top of the blue cannister looks like a shaft has been added, or the original motor shaft was replaced with a long one that sticks out both sides. The blue cannister itself also swivels with two quick-release brackets so that the belt on the bottom can be adjusted. The bottom of the blue cannister holds the pulley that goes to the head itself. It looks normal to me.



And that's about it. Without a manual all I can do is guestimate from online info that the mill dates to the seventies or eighties. Is that blue cannister the size of a certain mount for phase 3 motors or was it some off-the-wall contraption that I will never find a replacement for?
thanks
Joe


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## David (Sep 2, 2012)

Joe sorry to hear that motor has been modified!  I have run into this before on other equip.  What I have done is to disassemble to a point where I know what I am dealing with, then measure, measure.  If the blue motor is no good and you want to buy/install a new one, I would start sourcing the hp you want and start checking frame configurations.  You may have to fab a base plate that would adapt the new motor to the head flange.  Others may have recommendations on motor vendors.  I have had good luck with my local shop, they are willing to help above and beyond just selling a motor.


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## Pacer (Sep 2, 2012)

That appears to be very similar to Bridgeport and its many copies (My Chinese BP clone is very similar to that) Youll need to get that Rube Goldberg stuff off there and be able to see the mount - and get a pic of it, and as David says get some measurements. Its fairly common for the BPs motor to fail and be refitted with another type motor using an adapter, some of them had an oddball mounting configuration. It shouldnt be something that is gonna cause any problems that cant be figured out.


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## Rbeckett (Sep 2, 2012)

Most elec motors follow a standard NEMA configuration and should be easy to source once you know what you have.  As far as wiring I have to get an expert because I dont know enough to not get myself electrocuted, so I leave it to them.  The blue can is probably not good especially if the magnets/windings where damaged by the heat of welding on it.  Look at the NEMA Standards and you should be able to pick out your mount from the drawings and measurements and come up with a suitable direct or nearly direct replacement.  Adapter plates with multiple hole and spacer configurations are very common and completely acceptable for strength and durability.   I think the original motor was a two speed and one speed commonly dies and folks just slap a motor on to replace them.  The dual stacked pulley design will be good to keep if you really want to slow down the quill and use it as a verticle lathe and mill.  Just me .02, hope it helps.  As an add on, the voltage to the red wires is only 110 too, there is no connection to 220 anywhere in that box I can see.  Unless the are tapping the white wire and combining it to get 220 at the motor.  Thats dangerous because it floats the neutral line at a 220 potential... Not good from my very very limited estimation and experience in electrical wiring.
Bob


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## joe_m (Sep 2, 2012)

I took the motor(s) off to make it easier to lift the head off myself to remove that riser. While it's down I measured what I could - but since I can't get either of the pulleys off I'm a bit limited. The top one has a tiny hidden set screw I can't get ahold of, and the bottom one is held in with a key and I don't have a pulley puller. So I measured two adjacent holes and did the a squared + b squared = C squared thing to get a radius of 3.21ish and a bolt circle diameter of 7.424ish. I figured that, armed with a shaft length of 4-4.25" and a shaft diameter of 3/4" would get me close on the NEMA chart.

Nope, no such luck.
The only face mount I see with a 4" shaft is 254TC and 256TC, which has a bolt circle diameter of 7.25 (pretty close - and I was using a tape measure for my measurements...) But the shaft size is 1-5/8 for those, so that's not it, although now that I think about it the shaft on the TOP might be 1-5/8. (and just for grins i checked to see what Baldor makes in either of those styles and the smallest is 3-phase 7.5hp.) 

I was able to lift the two motors bolted together and the 220v one is much heavier than the blue can, so I'm sure the inside has been stripped.


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## pineyfolks (Sep 3, 2012)

If you want to go cheap, make a sleeve or bore the case out on the blue motor and use it as a base for another motor:thinking:


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## Hawkeye (Sep 3, 2012)

Joe, if I'm understanding your OP, they have the light coming off one of the power legs and returning via the ground. Is that correct? If so, I'd fix that first. It's never a good idea to use a ground wire as a power conductor.

Fixing it may involve running a 3-wire from the panel to your receptacle location and either using a 4-pin connector to plug it in or direct-connecting the mill through a junction box (my choice). Then the light can be run from one power leg and returned through the neutral, as it should be.

BTW, nice score on the mill. That's more what I had in mind when I was thinking of getting a knee mill, not the 1 1/2 ton monster I call 'Miss Vicky".

If you end up running on a single-phase motor, I'd consider keeping the blue canister as an idler shaft, so you have the full 10 speeds. If you go to 3-phase with a VFD, it's history.


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## AR1911 (Sep 4, 2012)

I guess I missed the message where you told us what kind of mill this is.


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## joe_m (Sep 4, 2012)

AR1911 said:


> I guess I missed the message where you told us what kind of mill this is.



It's a Taiwanese vertical mill by "Select Machinery Co." The original post is over in the milling machine section:

http://www.hobby-machinist.com/showthread.php/8288-Another-Mill-to-ID

Joe


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## Clearprop (Dec 17, 2012)

A user on other forum's that goes by "Rakort" also has this mill. He replaced the original motor with a 2hp 3ph by machining the armature to accept the original pulley and milling a mounting base that matches the stock base, IMO he did a great job. You might be able to just re-use your base from the original motor to do something similar.

I've been in contact with him and so far it's still a work in progress. I was able to use my original 1.5hp 3ph motor by hooking up a teco VFD, works like a charm. I'm very glad I learned about VFD's, I would otherwise have spent just about as much adapting a single phase motor that wouldn't work as well. I'm still in the process of wiring up the "remote" controls for the VFD, I have all the switchs and pots for adjustble speed, jog, fwd/rev, and E-stop, I just need to hook it up.


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