Elliot Omnimil 00 (motor options?)

Towforce

Member
Pondering the future of a Elliot Omnimil that I have ( here is a good example of the my "OO" http://www.lathes.co.uk/elliott-omnimil-00/page2.html ), not sure I'm going to keep it or ? but I was re-evaluating a problem that kind of has me stuck.

The overhead had a stock 3/4 220 1ph motor. With this motor, you could fully articulate the mill angle and the motor would clear the horizonal support (pushed back when not in use). The stock motor was "open" and had no rear cooling fan. I have yet to find anything to replace it with. (the original motor had a broken output shaft that had been repaired... not a good repair and was a source of vibration). This is what the stock motor looks like:

Stock Mill Motor.jpg

I've tried various base mount motors and they tend to have too much diameter and end up striking the support shaft. Seems what I'm looking for is a very short old school motor, any suggestions? (and I've gone through some pretty endless lists of motor options from my motor supplier). I did a mock up of a 1hp Leeson and its pretty much the same problem with everything else that I tried, in order to have enough lower clearance it moves the output too high to line up with the belts.

mockup motor.jpg

One possible solution is to fine a conventional base mount cap start motor and invert the motor with the shaft facing down. Ridiculous amount of reengineering that could be avoided if I could just find a "short fat" 3/4-1hp base mount motor.

Thanks for thoughts....

Martin
 
Pondering the future of a Elliot Omnimil that I have ( here is a good example of the my "OO" http://www.lathes.co.uk/elliott-omnimil-00/page2.html ), not sure I'm going to keep it or ? but I was re-evaluating a problem that kind of has me stuck.

The overhead had a stock 3/4 220 1ph motor. With this motor, you could fully articulate the mill angle and the motor would clear the horizonal support (pushed back when not in use). The stock motor was "open" and had no rear cooling fan. I have yet to find anything to replace it with. (the original motor had a broken output shaft that had been repaired... not a good repair and was a source of vibration). This is what the stock motor looks like:

View attachment 31206

I've tried various base mount motors and they tend to have too much diameter and end up striking the support shaft. Seems what I'm looking for is a very short old school motor, any suggestions? (and I've gone through some pretty endless lists of motor options from my motor supplier). I did a mock up of a 1hp Leeson and its pretty much the same problem with everything else that I tried, in order to have enough lower clearance it moves the output too high to line up with the belts.

View attachment 31209

One possible solution is to fine a conventional base mount cap start motor and invert the motor with the shaft facing down. Ridiculous amount of reengineering that could be avoided if I could just find a "short fat" 3/4-1hp base mount motor.

Thanks for thoughts....

Martin
Might not be what you are looking for, but I think I would try and source an adequately sized 3phase motor and just use the one pulley size that you can line up and add a vfd for spindle speeds.
 

YotaBota

Mike
Premium Member
I would send pictures of the motor (with dimensions) and data plate to these guys and see what they come up with, they are also a good source for VFD's.


I bought my VFD form them and a few others have bought motors as well.
 

Towforce

Member
Might not be what you are looking for, but I think I would try and source an adequately sized 3phase motor and just use the one pulley size that you can line up and add a vfd for spindle speeds.
Curious, if I went with a 1700-1800 rpm 3ph, with the VDF, how would the overall amp draw look? (Never worked with VDF's but does pose an interesting option given I'm electrically starting with a clean slate and I think there are VDF's that take remote signal inputs to assign rotation allowing me to install "stock" looking front controls)
 

Downwindtracker2

Well-Known Member
You are looking at the motor, what about the jack shaft ?. A longer shaft with a connected spacer between the sheaves. Or a keyed shaft which PA has on sale in their coming flyer. That would require a bearing mount. From the looks of the belt, it doesn't look like a "A" series, 3L ?? I would use the bottom sheave and switch over to a common "A" for the new motor and top sheave. Just an old millwright's thoughts. That mill well worth the effort.
 

YotaBota

Mike
Premium Member
I don't believe the amps will change for the same HP rated motor whether it's single or 3ph, but my beliefs have been proven mistaken in the past, lol. A motor person should chime in here shortly.
I have a 1.5hp 3ph motor and vfd on my lathe and run the original on/off and drum switch for rev/off/fwd control then added a freq control pot to fine adjust the spindle speed with a tach for bling.

1677258753811.jpeg
 
I have to be honest, electrical is not my strong point. While I have purchased a couple of them now, I have yet to install one. I'm still a little bit scared of letting the magic smoke out of any more gadgets, so I am still in the stage where I sneak up on it and poke it's box before running away ......
Hasn't bit me yet, so I don't run as far away as I used to......:rolleyes:
Fortunately, there's some brilliant minds here that will be along shortly to set us both straight. ;):p
 

jcdammeyer

John
Premium Member
Interesting method for adjust belt tension and for that matter replacing the motor belt with that long stud in the way.
img30.jpg


3/4HP is 754W/HP * 0.75HP = 565W
I put the 80SM-M0320MAL on my milling machine knee because I didn't need more than 2000 RPM. With reduction pulleys I still get 120 ipm on the knee which is plenty fast.

I would suggest the same motor which at 730W would allow the same sort of speed ranges you get now but in one belt position would give you variable speed over quite a wide range. And take a look at the motor dimensions. An easy fit since it's much smaller.

Yes in many ways overkill but OTOH, if you move to CNC you have variable speed and the ability to do power tapping.
 

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Interesting method for adjust belt tension and for that matter replacing the motor belt with that long stud in the way.
img30.jpg


3/4HP is 754W/HP * 0.75HP = 565W
I put the 80SM-M0320MAL on my milling machine knee because I didn't need more than 2000 RPM. With reduction pulleys I still get 120 ipm on the knee which is plenty fast.

I would suggest the same motor which at 730W would allow the same sort of speed ranges you get now but in one belt position would give you variable speed over quite a wide range. And take a look at the motor dimensions. An easy fit since it's much smaller.

Yes in many ways overkill but OTOH, if you move to CNC you have variable speed and the ability to do power tapping.
.......see, I told ya one of the smart ones would come along. :p
 

Downwindtracker2

Well-Known Member
I'm struggling with the programing of my VFD, so I won't be the one encouraging that route. But a new TEFC motor is in order. I would go with a 1hp . Your original 3/4hp likely had at least that amount of grunt. Whither a 3ph VFD or 1ph, you will still need to be able to the change belts for speed ranges. . Walking the dog, I got to think about the problem,if the bearing mount for the jack shaft is sturdy enough, I would be tempted to simply cut what looks to be a one piece double sheave and bolt the new sheave on top. I did something like that when I changed motors on my lathe, the more powerful 3ph had a smaller shaft.
 

Downwindtracker2

Well-Known Member
I notice the fiberglass guard , a higher back section for the raised motor and sheaves would be needed with my suggestion. Molding , or making panels with fiberglass is silly easy. If you take a piece of the machine into a paint store they should be able to colour match. I've had Delta grey, General green and RongFu creme very well matched.
 
Try a motor rewind shop or two, they may be able to help you..

Bring the old motor and they can tell you the frame size required, will limit you hp selection to what is currently available.
 

Towforce

Member
Try a motor rewind shop or two, they may be able to help you..

Bring the old motor and they can tell you the frame size required, will limit you hp selection to what is currently available.
Through my work I often deal with Armature Electric (Vancouver), they do great work, saved my bacon on many of my big commercial OEM stuff. Trouble is they don't really like to mess with the small frame stuff because the aftermarket tends to have it covered. Good point tho... I should just take the original motor in and get an opinion. What I really need to do is get off the fence as to if I want to sell it as is or get "it" back in the game?...

BTW, spacer idea was interesting (lifting the head attachment 1/2" might be all that is required).

I do prefer to keep it close to stock, no real experience with VDF's, I'm old school, like to build interlocked electromechanical motor reversers (much of the new stuff is small and reliable). As to the belt concerns above (access to the main drive belt).... the steel shaft running up the middle between shives is simply a support for the Fiberglass cover, on screw and the belt can be removed. Can't recall but I believe they are standard B belts.

M
 

Towforce

Member
VFD's well easy to wire, reading the manual and setting up the settings a little more fun. But definitely worth it.
I accept that, tho.... at my work, every time the company launches a new product with some fangle microprocessor (product of the devil).... and the field reps spend hours on the phone with tech service... followed by "replace the board" ;-) .... Relays are all warm and comfortable!

M
 

Downwindtracker2

Well-Known Member
One motor repair shop told me, they specialize in large metric motor that aren't easily replaced . He gave me a name of a guy that did small motors on the side, who I couldn't reach. Since the motor on my RF-45 mill is bit odd, I couldn't just replace with an off the shelf, instead I had Teco in Abbotsford repair it. They have a repair shop in back. He said he would look at it when he got a chance to work on it.

Our mill used Beaver Electric, BTW. I asked permission and dumpster dived for motors off of thrown out small equipment. Some still had the Beaver Electric sticker.chuckle.

My buddy forgot and left a small drill press running. The motor was just an open vented one, not even fan cooled. It caught fire and he caught *ell from his wife.
 
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