Pre 1952 Motor Frame Size help

[BrentH]

Hello,

A friend is restoring a 10 inch Utilathe that was build pre 1955. I have the same lathe built after 1955. The lathes are very similar, however the electric motor mounts are drilled and tapped at different spacing.

From the manual (old one) it says the motor fitted to his lathe should be a frame 69

From the manual - Newer one - says that my motor should be a 56J

Realizing that NEMA classification for fractional horsepower motors came into play 1952/1953 my motor designation and mount spacing on the lathe makes sense (except for the J, which is supposed to designate a special jet pump motor with threaded shaft. Mine is a 3 phase motor and no threading of the shaft - estimate manufacture around 1969)

For a frame designation of 69 I cannot find anything on this frame size. I can find frame 66 which has the same foot mount spacing (according to the bolt pattern on the side of his lathe) and is designated a pre 1952 frame motor.

Is the 69 a typo and should be a 66?

The objective would be to possibly relocate the bolt hole to a 56 frame pattern or a 56H pattern. I want to be sure the motor pulleys will be located correctly. The 66 frame gives a height to shaft center as 4.12" vs a 56 frame at 3.5" this may not be an issue as my lathe doesn't seem to have a problem with fitment.

Would anyone have any info on a 69 frame motor? or is it typo in the manual? (it could be as they have a 25Hz motor instead of a 50 listed as an option)

 

[Bob Korves]

Talk to a local motor shop about it? Bring pics and dimensions...

 

[Ulma Doctor]

The 56J is a pump motor

the 56 frame is loosely considered a universal motor for many retrofits below 3hp
the 56 frames will have a 5/8" shaft with the exception of the 56HZ which has a 7/8" shaft
the 56C is a face mount, sometimes as a threaded shaft, sometimes as a 5/8" shaft.
56 frames can have 3" or 5" spaced holes (56H,56HZ) on the longitudinal axis, most other factors are identical

 

[BrentH]

The 56J is a pump motor

Yes that is true ---- I made a typo ....My motor is a J56. Evidently not just a pump motor but pretty much all around application motor for heavier duty applications where a 1.25 service factor is applicable. The shaft is not stainless or threaded as applicable to a pump motor that you find if you put frame 56J as the frame. Interesting....

Talk to a local motor shop about it? Bring pics and dimensions...

This would be an ideal situation, however, we have no physical motor, just what the manual says is the motor to fit.

Anyone with info on an antique "Frame 69" ?

 

[RobertB]

Would anyone have any info on a 69 frame motor? or is it typo in the manual? (it could be as they have a 25Hz motor instead of a 50 listed as an option)

25Hz isn't a typo, some areas at one time, such as Niagara Falls, used to generate 25Hz power.

I would think it would not be too difficult to make some new mounting holes in a 56 frame foot to match the lathe mounting holes.

NEMA is US, Standard Modern is Canadian manufacturer, maybe 69 frame is a Canadian version of NEMA?

 

[BrentH]

Hi Robert,

Good to know on the 25 Hz - that is pretty interesting stuff and I will include that in my history write up on these lathes - I will continue the hunt for the 69 Frame - yes it could be some "Canadian" thing. The USA seems to have kept a lot better records, or at least published more. Its hard to find anything on Canadian Companies in the early 1900's and lots of records seemed to vanish as companies were bought out....

Thanks for the info!