Suitable Motor For Logan 200?

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I'm thinking ahead a bit to when my 200 rebuild will get a new motor, since I'm thinking about adding a
VFD. The old motor is a Walker Turner with a frame labeled 118D which appears obsolete. After measuring
up the mount on the drive box and looking at NEMA frame dimensions it looks as though a NEMA 56
frame will fit. Has anyone changed out their motor to this frame, and if so were there any problems
with the fit?
 
the 56 frame is loosly considered a universal fit motor.
i'm not familiar with a 118d frame.
the 56 should have a 5/8 shaft,
unless it is a 56HZ frame (7/8" shaft).
you may need to account for differing shaft diameters between your motor and the replacement
 
The Frame size to get a 1/2" diameter single-ended shaft is 48. Other mounting dimensions are similar to the 56. These were once common but are beginning to be more difficult to find, at least with certain options.

Also, don't accidentally buy a 56C frame size motor. This is flange mounted.
 
I'm guessing the WT motor has a 5/8" shaft. If it's capacitor start I'm also guessing it's a model KAB5 (maybe with some letter after it) The attached document shows the Walker Turner motors and frame sizes. Atlas also sold motors made by Kingston-Conley that have similar frame sizes with some minor differences like the location of the starting capacitor.

Logan sells a replacement motor that is a 56C frame (flange mount) but it also has a footed base.
 

Attachments

  • WTMotors.pdf
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The foot mount 56 frame motors appear to fit pretty well, but you may need to pad it up a bit so the motor j-box can clear the ear on the casting used for tension adjustment.

I believe an extra 5/8 inch or so was required - just longer bolts and a few extra washers - unless you get fancy and turn four nice pads.
 
Thanks for all your replies. I spent some time measuring and I think a 56 will fit IF the mounting base is slotted and the electrical box doesn't interfere. I found a Marathon in
3 phase that has no capacitor and no electrical box to interfere with the drive box. My Walker Turner has the capacitor mounted on the opposite side of all the modern motors
I looked at online: it's actually a pretty tight fit around the motor. None of the Baldors that I could find will fit for that reason. I need to look through Marathon's listings for single
phase 220 motors: if I find something that fits I'm GTG since my breaker panel resides right next to where the lathe is located.

I'll also have a look at the 48 frame and see if it's possible.
 
Remember that the 48 frame has a 1/2" diameter output shaft. Which would require you to find a new motor pulley or bush the existing one.

It is possible to relocate the start capacitor. But you will have to completely disassembly the motor to do the conversion. If you have to go that route, you're probably better off taking the motor to a rewind shop and having them do it. The two wires going to the capacitor would have to be rerouted. Plus two holes drilled and tapped and a clearance hole for the wires drilled.
 
That sounds wise. And the 56 is far more common. Your only problems should be the location of the capacitor and the location of the junction box. Some 56 frame motors have the junction box cast integral with the right bearing carrier. That would solve that clearance issue, leaving only the capacitor location to solve.
 
I trolled through the Marathon catalog and found some 115V motors which have split phase starting, and therefore no capacitor. I know running amperage is higher with 115,
but it will have a dedicated outlet from the CB panel, and it's no worse than my drill press. They have no junction box on the side, so no problem mounting
them. I'm also going to take some careful measurements to see if a 56 frame capacitor start motor will fit. Marathon has a few with no junction box hanging off the side.
 
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