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    chris mabbott

      I’m a happy camper as I finally picked up a vintage motor for another lathe, so now I don’t have to swap out all the time.

      I plan on rebuilding this here little devil as soon as it reaches my door, hopefully this week as I have been trying not to chew my nails off with impatience 😆
      This is one of the things I love/hate about shopping mail order, the thrill of the hunt, the satisfaction of the purchase, then the sheer, unbridled passion of actually fondling your new gem in sweaty hands 😈 But the waiting, oh the waiting LOL

      Ok, here is the motor, apparently rescued from a retired watchmakers shop, as you can see from the sellers pics, the wiring is bad, the motor is filthy inside, and I can only imagine what the brushes/rotor/stator look like.
      I would hazard a guess and say that the bearings are past their due date also..

      I am planning on doing a photographic, step by step rebuild process, and although I am sure many of you have done this before, there may be someone who hasn’t and it might help.
      I may be doing something incorrectly also, so any tips are always welcome..

      For now, until it arrives, here are the pics..

      chris mabbott

        I couldn’t find much info on this motor only that it’s from the 50’s – 60’s, and even that is unsure..

        Look at all that yellow gunk on the bearing caps, it sure looks like the bearing lube has escaped and run out, I’ll be curious to see if they are the sealed type. Regardless, I will replace them with either American or Japanese bearings, which are the best.

        chris mabbott

          Mmm, look at all that dust just waiting to be cleaned 😆 I can imagine, just from the photos that …

          1. The inside is full of mierda ( pardon my Spanish:-)and efficiency has been reduced by 40%
          2. That the rotor/stator is rusty, because of the humidity in the UK.
          3.That I’m going to be like a pig in poop enjoying restoring this, if I can find parts Doh!

          david pierce

            If you replace the bearings keep in mind that this is a motor and not a machine headstock. ABEC 3 grade bearings are fine for motors and are the bearings that are normally used for electric motors. Higher grade bearings (ABEC 7, ABEC 9) can be very expensive and unnecessary for a motor application. Replacement bearings can be ordered by cross refrencing the serial numbers or by measuring the OD, ID, and thickness in metric units. I am assuming that this is a universal motor and has a wound rotor. Make sure the brushes are still good and the commutator does not have brush carbon in the spaces. The cracked lead wires can be replaced or encased in shrink tubing which can be shrunk with a hair dryer. The brass can be polished back to new with Scotch Brite and motor oil.

            chris mabbott

              Hi David,

              You assume 100% correctly, it is a universal motor & I am also banking on it being a wound rotor due to the brush config.. but I am open to surprises when I pop the hatch, no telling who has been in there before me 😆

              Bearing wise, I’ve had a lot of success using full ceramic bearings on motors over the past few years, they are a lot more durable than the regular steel type and not that expensive.
              Also, and this is the most important for me, electric motors, especially old ones, will always arc to a certain degree, due to poor contacting/out of round brushes or dust in the carbon slip rings, and always in the direction of the bearings, as the arc moves outward drawn by the bearings weak field, especially if they use a lithium or graphite based grease as most sealed mini types do, they are a perfect conduit.
              Once I install these bearings, the casing will have probably rusted away before the bearings fail 😆

              I’ve been using these full ceramic bearings on my pool pumps for a few years, since I first experienced them on applications in the energy industry, and they are great, even the reduction in noise is quite substantial.
              I wonder how they would perform on a lathe headstock because of their high speed capabilities, toughness, and minimal lube requirements?

              I’ll probably have to change the brushes, and even if they’re ok, which I doubt, I’ll change them and the springs/holders, anyway because these are probably 30+ yrs old. I have a special cleaner for the windings and after I soak them and remove any crud/dust, I’ll use a sealant, for motor windings, to protect it from the humidity and improve the field.

              I was hoping that my best friend, the mailman, would have delivered it today, but no.. 😥

              Stay tuned for the tear down pics and thank you David for your helpful suggestions.



                Looking forward to the teardown to reassembly. I have an old Zenith cleaning unit that I to am going to have to do the same thing to my motor. Always looking for tips. In my case I may take it to a nearby company to have it done. I could not stand the down time very long. I use this machine almost daily. Looking for an old standby. I wish I had another “cheep” unit just to fall back on. In time. ;) . Ed.


                  I will be watching closely too as I know nothing about electric motors and I have a few that would benefit from servicing.
                  Good luck :)

                  Bob Tascione

                    Me too Paul!
                    This thread should be a big help for many of us.
                    Chris, do you have a supplier for these bearings that you would recommend?

                    chris mabbott

                      Here’s the link Bob.. and i will add that you will notice how quiet these things run, there is no cage/bearing chatter as with steel BBs Bon chance.. :ugeek:


                      chris mabbott

                        @ewinrow wrote:

                        I could not stand the down time very long. I use this machine almost daily. Ed.

                        If you pick up all of the gear you need in advance Ed, you can have the motor completed in a couple of hours, or less. Not much to them.
                        You can provide the frame info to an electrical supply company, they should be able to match the brushes, unless it’s the brushless type. You can also pop off one of the end caps and photograph the bearing, get the measurements/part numbers etc, then pre order the bearings. You will need the following..

                        Standard/metric socket set, and combination wrenches
                        A couple of flat screwdrivers, for prying LOL
                        One of those cheap small bearing puller kits, they used to be about $20 for three different sizes.
                        A small blow torch or heating element
                        a brass wire brush or dremmel
                        Isopropyl alcohol, it is a fairly mild solvent used for general surface cleaning of electronic equipment
                        some rags
                        Hammer, soft faced type
                        A piece of pipe that will just fit over the shaft and touch the inner race NOT the seal.
                        A piece of hard wood to set the end of the shaft on.

                        Unfortunately I am no longer part of the North American convenience group like you guys, where I could go into Albertson’s, buy bread, steak, beer and ceramic bearings 😆 So my hunt is a quest..


                        Bob Tascione

                          Thanks for the link to Bocabearings Chris!
                          Really nice that they deal with small orders. I’ll check it out a little later today when things slow down around here a bit.

                          chris mabbott

                            You’re welcome Bob & welcome home..

                            Well, my motor arrived with a few other goodies that I’ve been anxiously awaiting. The problem is that I’m having a bit of construction done around my dungeon area, I let the guys use the head, out of pure courtesy, but they’ve kinda made it into their lunch room, much to my dismay, also, their more valuable tool storage area, so yesterday when I went down and saw all the crap and dust inside.. I FREAKED 👿

                            I had to set a few ground rules and I think they got the message from the thunder cloud above my head, so I’ve covered everything in plastic and tried to clean up… So the motor/watch rebuilds will have to wait until sometime next week (Bob, I need a crying smiley please)

                            I went down this evening and did a clean up, then I could not stand to wait until next week to see what was wrong with the Hamilton that arrived today, I know, I know 😆

                            This is what I’m faced with, to the right of the guy is the entrance to my little shop 🙄


                            chris mabbott

                              I Finally got around to working on this motor, got it apart and found a few surprises within..

                              So here it is ready to start the tear down..

                              chris mabbott

                                First remove the pulley which is held into place with a simple grub screw, then I’ll use a fine 1000 grit emery cloth to clean up the shafts before removing the other parts, plus a small shot of WD40, this is where this stuff comes in useful.

                                Here I’ve removed what I thought were bearing dust covers, held in place by three screws. You can see what I think is a fairly new felt … dust cover? I haven’t seen anything like this previously.

                                chris mabbott

                                  Next I’ll remove the two sets of brushes. They look to be in good shape and lots of material left, although dirty. sorry for the blur but it was bouncing around on the spring 😆

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