Question about old electric motors...

[Doc Nickel]

A few weeks back, I asked about vintage motors, something that might be an interesting style and/or period match to my circa-1910 Stockbridge shaper (for which I need a motor anyway.)

It was kind of a lark at the time, as I'd narrowly missed what was supposed to have been a nice example- which is what gave me the idea. I soon dropped it for lack of time and sources, and the general disinterest in having a huge old motor of questionable quality shipped all the way to Alaska.

However, I recently happened across this:



Despite the name of the image, it's not a motor off a shaper, that was just a handy name I gave it to keep things sorted in my dump folder. The owner says it's actually out of an old butcher shop that was line-shaft powered.

Here's the data he gave me:
Alternating current motor
Type llTBA single phase 60cycle 3hp cont. duty 40degree C.
25% overload 2 hrs. @55 degrees C.
1750 rpm 110v - 32 amp 220v - 16 amp
Wagner elec mfg co St Louis, USA

He says an electrician friend checked it out- he smelled ozone but it seemed to run okay. I'm assuming worn brushes?

Now, considering this entire thing is purely for looks- a modern 3HP would be far cheaper to ship, more reliable, and a third the size (this one's almost two feet long counting the pulley) - is there any real issue I ought to know about, if I used something like this? Will it draw more power than a modern 3HP? Require an oddball starting circuit? Something else?

Doc.

[kjbllc]

Well brushes would be one thing to think of if is has brushes, where are you going to get them. I do believe that it would be less efficient. The bearings may also be a problem being so old. It may also not be from the early 1900's and more from the 30's or so. Somewhere along the line they up the voltage ratings on the motors. the early ones that I have seen are 107. The may be an issue with the higher voltage and the age of the insulation on the windings, cracked and brittle. If that goes you can have it rewound. But overall I think that you are looking at something that is a 50/50 proposition. You may hook it up and it runs for ever with no problems, or it may burn up in the first 5 minutes. I would get it if it is cheap, and use it to run a 72" sander with that nice drum on the end. This is just my opinion though others may have had different experiences. good luck.

[bruto]

If the horsepower is reasonably matched to the load, those brushes won't stay engaged for long (I'm assuming a repulsion-induction motor), so if there is much of them left now it will probably last well enough. It's common for those to give a whiff of ozone. One real advantage of these motors is that they can run on the starting winding indefinitely without damage, so they are well suited to heavy and slow starting machines, or machines that occasionally bog down. It's hard to burn a repulsion induction motor out. If it's in good running condition it should last forever, and those old motors, with their big oil-soaked sleeve bearings, tend to run quietly too. Just make sure your belt alignment is good, because they usually float a good deal, and don't take thrust well.

[Bob Ford]

Doc

This looks to be a repulsion induction motor. Torker had questions of one a few months ago. If the insulation is good you should have no problems. Might have to fiddle with the forward reverse settings to get full power. The bearings I think are sleeve and you might have to re-sleeve and adjust the shims for end play. It is a heavy motor and the wound rotor makes a good flywheel,should put out even smooth power. The new higher voltage should not be a problem and hook up is straight forward. Just get breakers and switches of the correct size. I have not wound motors generators since the early 1960s, but those motors were sought after for some applications. Suggest a clamp on amp meter for you too!

Bob

[mwechtal]

Here's the data he gave me:
Alternating current motor
Type llTBA single phase 60cycle 3hp cont. duty 40degree C.
25% overload 2 hrs. @55 degrees C.
1750 rpm 110v - 32 amp 220v - 16 amp
Wagner elec mfg co St Louis, USA

That's odd. Deg. C specs on an old US made motor?

Mike

[Forrest Addy]

Old motors like that can be a crap shoot.

The leads may be very fragile in that the insulation may crumble off the wires. Be very careful when working with the leads and be prepared to follow them back to the motor's internal connections and replace them if need be. A widely used practice is to slip shrink tube over leads with crumbly insulation to contain and reinforce it. The end emerging from the windings has to be laced tightly to the winding mass so that movement of the leads doesn't crumble off at the point of flexure.

At the very least I would suggest a disassembly, inspection, a megger test, bushings and oil rings etc, inspect the brush rigging, replace the brushes turn the comm, then finally a bake, dip and bake for the stator. Since the armature is wound bake and dip that too.

All this is belt and suspender thinking; you may not wish to go through it all if the motor has never been out doors. At the very least open it up and vaccuum out the dirt and dust.

One thing that may be a long reach. Is is a metal cutting ram shaper or a vertical spindle wood shaper. You don't say. I'm guessing a metalcutting ram shaper. But if this motor is intended for a vertical spindle wood shaper, it will have to be vertically mounted. Are the plain bearings suited for this service? It looks to me like it's furnished with oil rings (those little coverplates are where they are installed in the bearing cavity) but maybe not. It needs to be checked out. Most horizontal service plain bearing motors are not suited for vertical service.

A clever home shop machinist can retrofit it with ball bearings but if he hires the work it won't be cheap.

I love those old "boulder" motors. They have a nice shape that hints at authority.

[Doc Nickel]

Is is a metal cutting ram shaper or a vertical spindle wood shaper. You don't say. I'm guessing a metalcutting ram shaper.

-It's an old 16" Stockbridge that I picked up a month or so ago (but have yet to haul home.) As I said, the only reason I'm considering this old motor is that it might make an interesting period match to this turn-of-the-century machine.

Yeah, I figured it'd probably have sleeve bearings/bushings. That''s not too much of an issue, as the Stockbridge has no oil system, so I'll have to keep at it with an oil gun anyway.

But, presuming the motor works and won't crash on me anytime soon, there's still the issue of mounting. I'd have to set it on the floor, and figure out some way to mount it- I don't want to drill the concrete floor and put in redheads, which means I'd have to... I don't know, make a low platform for both the shaper and the motor?

On the other hand, a smaller, lighter modern motor I think I could build a frame to mount it to the machine, off the pad just below the input pulley shaft. It's original purpose was an outboard arm for a large flat-belt pulley, but with some thought and design time, I'm sure I could make a bracket that would hold a motor- and possibly a short jackshaft/step pulley if neccessary. (I'm still not sure what kind of input RPM I need to give it.)

Doc.

[bruto]

If the shaper has bolt holes in the base, you might be able to get away with simply bolting a heavy plate or piece of angle iron to the base on one side, and bolting the motor to the plate, or attaching a plate to the angle iron.. If you put the motor on a hinged mount, you could tension the belt with its weight.

[ammcoman2]

Re: Deg. C specs on an old US made motor

Yep, one would think this to be odd but for some reason the motor manufacturers went Celsius from the early thirties (and, perhaps, earlier). Thermostats were marked in Fahrenheit.

At the plant I worked at for many years we had this dual personality. All motor protectors (Klixon) were listed in degrees C and the thermostat line products were marked in degrees F. Interesting how one could easily switch back and forth.

Geoff