Reply To: Motor Rebuild

[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.

Chris