Rebuilding/Refurbishing an Atlas Motor

I know this is an old thread, but I just wanted to give Lou a deep thanks for posting this whole thread on rebuilding the old Atlas motor. It totally saved my bacon as I have a very old Atlas 7b shaper with a 1/2hp motor that looked almost exactly like yours. The main difference being it has bearing oilers front and back.

I got it out of a barn sale and it's very apparent it's sat for many years perhaps decades. When I tried to start the motor it just hummed. When I turned it over it was very stiff and after putting some spindle oil in it freed right up and would start. But not strongly. After reading your whole thread I got to suspecting the mangled wiring and the start cap. When I checked it close the guts literally fell apart in my hands. But nowhere was there any markings on it as to how many mfd. But luckily you mentioned what size your was. I ordered one and it works like a champ now. Thank you so much because nobody I talked to could tell the size cap this motor took.
 
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Thanks for the kind words, and nice to know that the thread helped out!
 
Nice careful job, that's what it takes. Good for another 50 years. :cool 2:
Mark S.
 
I can't begin to tell you how dead in the water I would have been without that tidbit of info. It didn't say on the data plate what size the cap needed to be. And every supplier I talked to said they didn't have any info on that old of a motor and all they could say was " yeah, and those old motors are very finiky about the size of the start cap".

Ever looked through start cap specs? It is waaaaay beyond me. Most anybody would say is why am I still trying to get an old motor like that going? A little oil and a $15 cap and it's good to go. I'll bet if I'd tried to replace the motor it would have been a bit of a headache adapting it and I just couldn't at least try and save this old motor. It truly is ancient as it's got oiler caps and the wiring inside the motor is cloth(possibly asbestos, but in perfect condition) and just hums and starts like champ now. Well worth the effort, thanks to Lou.
 
The motor is every bit as vintage and worth restoring as the rest of the machine, so it's certainly worth the effort. And new motors are not exactly cheap, either.
They really don't make 'em like they used to.
Mark S.
ps I don't think you have asbestos wire.
pss I disagree with your shop; there is usually some leeway on the start cap value. Smaller MFD values take longer to start with less torque. Larger values give quick starting but draw more start current, which is harder on the centrifugal switch. The voltage rating should be the same or higher than the original
 
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I have to admit I'm not a restorer, I'm a user. While I deeply appreciate machinery and tooling, I appreciate them for form and function over esthetics. I've got a job to do and love it when the right tool comes along. This old Atlas shaper was more of a rescue than a conscious purchase. It was all there including the vise, tool holder and most of the guards(missing only the motor belt guard which was obviously broken off in some kind of mishap which I couldn't see when I first saw it) and was too cheap to pass up.

It was filthy from decades of sitting but was also obvious that whoever used it originally kept it oiled. So it was that film that is oil and dust that is actually a great preservative of good machinery. And it was not stored outside thank goodness. It just has needed a really deep cleaning with kerosene, wire brushes and hand cleaner. I get the feeling over its long history it's been through many hands and some who didn't know what they were doing as far as how to use it or adjust it. It has been either crashed and broken the ratchet box or an adjuster came loose and crashed the box, as it's been repaired. There's been other forensic signs of past abuse possibly in transport. I seldom buy new machinery so every new to me machine is a revelation.

Thanks to Lou and his careful documentation not only was I able to observe what I'd be getting into if I needed to go into the guts of the motor, it also helped me ascertain if it was worth it. Not every old machine or component is worth the time and energy. But I could see this was and I'll trade some elbow grease and swapping out a component (the start cap) for the possible mess of adapting something new not to mention the expense.

I'm glad I found this post as it's also turned into a goldmine of info on the shaper archived on the site and made me become a member.

P.S. Look up cloth wiring, I was floored to find out it's impossible to know whether it's asbestos or not as it was widely used. I was just trying to help date the machine possibly through the fact it was cloth insulation and stumbled on to it. As with like anything like this as long as it's OK, not falling apart and I don't need to mess with it, I'm good to go.
 
My definition of restoration is pretty broad- even a "tune-up" could qualify I guess. You did a more thorough job than many would have.
I've seen asbestos covered wire but only on heater appliances, oven ignitors and toasters. On motors I've only seen cotton covered rubber, but I suppose some motors might have it. For modern high temp wires they switched to fiberglass but it's best not to breathe that either.
Mark S.
 
There really isn't any good reason for anyone to have used asbestos insulated wire in a motor. One that got hot enough to need it would be on it's way to scrap anyway.
 
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