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First time dealing with electric motor, please don't make too much fun of me...

First time dealing with electric motor, please don't make too much fun of me...

First time dealing with electric motor, please don't make too much fun of me...

(OP)
Hello everyone, I'm a computer engineer and a programmer, so I don't have any experience with large electric motors, please don't make fun of me, and please try to help me with my problem, and help me help you help me with the problem by asking me to any details you may need.
I took up woodturning a couple of years ago, and now the need for a sanding wheel arises, and like any wood worker, I'm trying to make my own.
I had an electric lawn mower which I didn't use anymore, on account of not having a lawn any more, and it was taking space in my work room, so I salvaged the motor to use in my new sanding wheel.
My problem is very simple, if I let the motor run (and it runs just fine), without any load on it (wheel not mounted, and blades of course already taken off), the shaft of the motor gets very hot, so much so that I fear for the wood wheel I've made for it.
Could it be this is normal? the motor itself does not get as hot as the shaft itself but it does get hot (as I would expect). I was thinking some lubrication could be in order, but it has no grease nipple, no indication on the motor to any treatment needed, in fact, the lawn mower was so cheep (it cost me 35 euros 5 years ago, on sale..), the motor has nothing on it at all to help me understand what, if at all, is the problem (again, this could be just normal for this type of motor...).
The only textual reference I have is written in the motor's start capacitor, and I hope this information is helpful:
KAI LU
CCC60 SH
16uF+-5% 50/60Hz
450C ~ C
25/70/21 P0
CE 2009
Should I just spray the whole motor with WD40? should I leave it like it is? any advice would be more then welcome!
(p.s, running on European 220v).

Thanks!

RE: First time dealing with electric motor, please don't make too much fun of me...

If one takes a brand new A.C. NEMA frame motor out-of-the-box, and bench tests it at the correct operating voltage, (simply to run it)
and lets it run for... a half hour for example, you'll find that the shaft is the hottest part of the motor.

RE: First time dealing with electric motor, please don't make too much fun of me...

What direction are you running the axle? A lawnmower is expected to run with the shaft vertical, the load below, and the motor above. This affects bearings (which may be bad!) and the thrust bearing position.

Are you running it sideways?
Does the motor turn easily by hand AFTER it is disconnected from the power supply? Be careful of your safety!

RE: First time dealing with electric motor, please don't make too much fun of me...

(OP)
Yep, it runs sideways now, not down facing like it was on the lawn mower... I didn't think changing the orientation of the motor would have an effect, but I guess it could have some kind of effect, the motor spins by hand, but not smooth, but then again, it's not a toy car motor, I wouldn't expect it to turn with zero effort, I can spin it by hand, but it won't spin to a stop slowly like an electric fan motor, for example. Also, it revs up and down pretty much immediately (again, with no load on it, with load it spins up fast, spin down slower then up).

RE: First time dealing with electric motor, please don't make too much fun of me...

If Its a lawnmower motor It may have a brake built in.
This operates magnetically when power is applied.
Its normally at the drive end.
If insufficient load is applied,the brake sometimes doesn't operate as the induced magnetism isn't strong enough.
This will cause a hot shaft.
You would do better just buying a sanding tool,safer and cheaper in the long run.

RE: First time dealing with electric motor, please don't make too much fun of me...

If it is a universal motor with brushes then some drag is normal. If it's an induction motor then it should be free unless there's a brake or similar.

RE: First time dealing with electric motor, please don't make too much fun of me...

(OP)
mmm... could be there is a break in there, and in that case, is there a way to disable it? I can't see anywhere a place for replacing the brushes, so I guess this means it's either an induction motor, or a motor made so cheaply as to be thrown away once the brushes are all gone... it's already mounted in my sander, but I can take it apart and take some pictures and link them here, maybe (probably) it will help figure out what kind of motor it is and how to deal with it.
Sure theode, I could buy a sanding wheel, but building one myself? can't pass on the manhood high from that project, among the wife, the little kids, the job and the bank on my heels, I need something to assert my manhood at... :)
Thanks guys/girls for all the help, and thanks for not smirking at my lack of knowledge, I really appreciate it.

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