Motor Replacement for 15" Clausing Variable Spped Drill Press

jbacc · Nov 26, 2017

Today I was out in the shop working on a few things including mounting a back-plate on a 4 jaw chuck. While drilling a 1/2" hole, the Clausing 15" variable speed

drill press made an odd sound but kept running but the chuck was not turning. Upon inspection, I noticed that the motor shaft broke where it enters the motor housing. The motor was still running but the shaft broke right at the base where it enter the motor frame. Never saw anything like it and while I do not know what kind of life it had before I purchased it about 15 years ago, I certainly do not abuse it or even work it hard.

The motor plate which I hope I can attach a picture of states that it is Doerr 1150 RPM F1756Y motor frame. Would someone be so kind as to enlighten me as to what frame motors will bolt up to the press and any suggestions regarding a replacement would be most appreciated.

Thanks in advance to any and all help/suggestions.

Joe

Sorry for the typo in the heading...

JST · Nov 26, 2017

Probably belt tight, and shaft broke off after years of being "sprung" a bit. Might have started before you ever had it.

The shaft can be welded, but it is VERY questionable as to why you would bother when motors are available. Those are common at garage sales, never mind other sources.

What is the dimension of the mounting bolt pattern, distance from "front" bolts to shaft, shaft diameter, and how high is the shaft off the mount surface? Those are the biggies for the frame size, and can be looked up on a size list., which I have

johnoder · Nov 26, 2017

I would not be surprised to find a F1756Y Doerr frame had at least some of the NEMA 56 frame dimensions

JST · Nov 26, 2017

johnoder said:
I would not be surprised to find a F1756Y Doerr frame had at least some of the NEMA 56 frame dimensions

Very likely. But SOMETHING about it is probably a special. Maybe shaft size, that's always a goodie.

crrmeyer · Nov 26, 2017

jbacc said:
Today I was out in the shop working on a few things including mounting a back-plate on a 4 jaw chuck. While drilling a 1/2" hole, the Clausing 15" variable speed View attachment 213827drill press made an odd sound but kept running but the chuck was not turning. Upon inspection, I noticed that the motor shaft broke where it enters the motor housing. The motor was still running but the shaft broke right at the base where it enter the motor frame. Never saw anything like it and while I do not know what kind of life it had before I purchased it about 15 years ago, I certainly do not abuse it or even work it hard.

The motor plate which I hope I can attach a picture of states that it is Doerr 1150 RPM F1756Y motor frame. Would someone be so kind as to enlighten me as to what frame motors will bolt up to the press and any suggestions regarding a replacement would be most appreciated.

Thanks in advance to any and all help/suggestions.

Joe

Sorry for the typo in the heading...

If you want to go the VFD route (variable frequency drive) for variable spindle speed, my son has a spare 3/4 HP 1725 RPM 3 phase 208/220/440V version of that motor along with some other parts from the top half Clausing 15" drill press (step pulley version) my son was given to help finance buying tools for his Boy Scouts Eagle Scout project. It looks to be a standard 5/8' keyed shaft if that matches your drill press motor.

jbacc · Nov 26, 2017

Many thanks to all of you for responding. I will take some measurements of the bolt pattern. Hopefully, as John suggested, the dimensions are close to the same as a NEMA 56 Frame.

I had not thought of going the 3 phase with VFD route. I might even have a 3 phase motor with the proper size shaft but it's a c-face motor, not sure if that matters as there is also a mounting plate. Going by memory so please forgive any conjecture on my part.

Crrmeyer, not sure what shipping might cost but if a I do go the VFD route, I will consider the motor your sin has, especially if Doerr's 1756Y mount proves to be unique and/or proprietary.

Thanks again to all for your help and insight.

Joe

Bill D · Nov 26, 2017

Since this has a variable pulley on the shaft I bet the motor shaft is longer then normal. I would ditch the variable speed and switch to step pulleys and a VFD. Come forward two centuries and enjoy the benefits of modern technology.
Bill D

jbacc · Nov 27, 2017

Good Evening all,

Just got home from work and went to the workshop as I remembered where I stored the 3 phase motor I purchased a while back. The good news is I found it and it is a 56C motor which mounts up perfectly. As John Oder surmised, Doerr's 1756Y designation does in fact match up to the NEMA 56 dimensions.

The motor is a 2HP motor but the bad news is, at least I think it is bad news is that it is a 3450 RPM motor. If you recall, the motor that was installed on the Clausing was an 1150 RPM motor. Assuming I left the original variable speed pulley's in place and power the 3450 motor with a VFD, would I have a usable range of speeds for mostly metalworking or would it run too fast.

If this is an option, what size VFD should I look for? I attached both a picture of the motor and the motor plate.

Again, in all sincerity, many thanks for any and all help and insight.

Joe

Can't figure out how to orient the pictures properly...Sorry.

Bill D · Nov 27, 2017

If you reduce the rpm by 50% the torque will also be reduced by 50%. So your replacement motor is a no go.
Bill

jbacc · Nov 27, 2017

Bill, many thanks and much appreciation for your help. I guess I need to start looking for a motor... Would a 1750 rpm 3 phase motor work or do I need to stay closer to the original 1150 RPM motor?

Thanks again,

Joe

jbacc · Nov 28, 2017

Spent some time searching EBay and other online vendors for a 3/4 - 1hp 3 phase 56 frame 1140 RPM motor.... Not cheap... I found a nice motor but it is a 143T frame and it appears the dimensions are different including a 7/8" shaft as opposed to a 5/8" of the NEMA 56 frame.

Any leads and/or suggestions to a good replacement motor would be appreciated. Going the 3 phase route will require a decent VFD making this an extremely expensive repair.

Thanks,

Joe

Search

Largest Manufacturing Technology Community on the Web

Search

Motor Replacement for 15" Clausing Variable Spped Drill Press

jbacc

Hot Rolled

JST

Diamond

johnoder

Diamond

JST

Diamond

crrmeyer

Stainless

jbacc

Hot Rolled

Bill D

Diamond

jbacc

Hot Rolled

Bill D

Diamond

jbacc

Hot Rolled

jbacc

Hot Rolled

Similar threads