Motor Mount Nema Dimensions

[evanthayer]

Hi All,

I am getting to the point where I will be mounting my motor to the horizontal drive unit on my 1952 9A. I have a new 3/4HP Nema 56 frame motor that I'd like to use as I believe is common on the 9A. As usual, I am doing things backwards as I measured the bolt holes on my mount AFTER I got the motor - and found to my non-surprise that they do not match. After some measurement and research I believe my motor mount is drilled based on the old, discontinued NEMA system and are "Old NEMA 66" spacing. Unfortunately, Old NEMA 66 does not match New NEMA 56 in either direction.

Old NEMA 66:
axial to motor = 5.875"
radial to motor = 5.000"

New NEMA 56:
axial to motor = 5.000"
radial to motor = 4.875"


NEMA 66 motors are no longer available. I assume my options are either using an adapter plate or re-drilling the existing mount for New NEMA 56 spacing. I did find a company "Overly Hautz" that manufactures an Old NEMA 66 to New NEMA 56 conversion mount. Has anyone had experience with that company or a similar conversion kit?

Anyone else deal with this some other way?

Thanks.

Evan

Existing Motor Mount:




New Motor Plate:

 

[Kevin T]

That company making adapters looks good. Did you find out how much they are?

 

[evanthayer]

a little pricy at $175 (about as much as the motor!!) but they are very nice and helpful on the phone. i haven't received mine yet so i cannot comment on quality.

That company making adapters looks good. Did you find out how much they are?

 

[evanthayer]

Here is the bolt pattern that came on my 1952 9A horizontal drive motor standard if anyone is interested.

BOLT PATTERN:

 

[jmm03]

do you have enough room to just use a piece of 1/2" thick plate and make your own adapter? e.g., plate bolted to original base and new holes drilled and tapped offset for the new motor. Jim

 

[evanthayer]

I probably did!

do you have enough room to just use a piece of 1/2" thick plate and make your own adapter? e.g., plate bolted to original base and new holes drilled and tapped offset for the new motor. Jim

 

[evanthayer]

Finishing Up

Getting back to this thread to post an update. I received the Nema 66 to 56 converter plates from Overly Hautz Motor Base Company. They shipped quickly and were well packed.

The design of the plates that Overly Hautz uses is pretty straightforward: (2) plates that are each drilled with clearance holes to fit the old Nema 66 bolt holes with 5/16" hardware as designed by SB. Each plate is also bored out and fitted with (2) 5/16-18 threaded collars that are spaced for new Nema 56 and deep enough to accept a 3/4" long bolt with a flat and lock washer.

Here are some images of how the plates were received:



And a close-up



Nothing too special with how they were manufactured: plasma cut plates with a few spacers stick welded in. Plates came lightly primed and oily as expected. It was easy to clean them up, prime, and paint them to match the lathe:



While the construction looks middle-of-the-road, the fit was very precise. The plates went on in a snap and the motor bolted up exactly in the middle of the adjustment range, i.e., perfectly. No bumping or cursing to get it on, too!





To summarize, the Overly Hautz company is easy to work with and quick, the plates while expensive work great the first time. The design is straightforward and could definitely be re-created at home, although I am happy to have not had to do it.