Lathe Motor

[The_Yellow_Ardvark]

Yesterday my Cornett Lathe decided to stop working. It was working ok.
Then, after I took 10 minute break, it would not turn. It sat there humming at me.



Striped of the belt to see if it would run with out load.
It didn't


So it was striped off the bed and opened up.

On the bench the shaft would not turn with the end caps on.



Yet, when the Rotor is spun in each end cap it spins freely.



I am guessing that the brass ring and Object is designed to cut the power if the engine goes to fast.

So, any pointers on what to check?

 

[Seadog]

No, that's the centrifugal switch to disconnect the start capacitor.

 

[The_Yellow_Ardvark]

@Seadog
There is no start capacitor, on the motor as I can see.

 

[dan treg]

it may be a Resistance split phase motor and switch takes out the start winding leaving just the run winding at a certain speed. also from your description unless ive misunderstood do you have a mechanical rather than electrical issue. are you saying with motor assembled the shaft wont rotate by hand ?

 

[daleyd]

Looks like the same motor as my drill - yes it’s a split phase motor and that brass centrifugal switch takes out the start winding.

Mine was stuck when I got it, was full of sawdust - I stripped it down and cleaned everything out, now you can hear a definite click as it starts and gets up to speed.

From your description it sounds like something is binding?

 

[R-D-R]

Had similar problem with the cromton on my fobco star. Its a split phase with a start winding and centrifugal switch. Stripped it all down (broke the switch board in the process) obtained a replacement and it all worked perfect from then on.

 

[The_Yellow_Ardvark]

Well I striped it down, rebuilt it and found nothing wrong.
Put it back together.
It spun for about 20 secs. and jammed again and started humming at me.

But This time I found something.



The case has a crack on it. Now I didn't see it before, so I don't know if that has a bearing on it.



But when the motor is stalled you can see the crack flexing.

Looks like old damaged and now during the move and rebuild I must of caused it to finaly go.

So a new motor is needed.

 

[Pete.]

Err, what make is that motor? English Electric?

Ah, don't worry, I see it's a hoover motor. The base is just like an English Electric one I'm just about to lb in the scrap. I thought the end bell might fit.

 

[The_Yellow_Ardvark]

Hoover.

 

[Anguz]

got a picture of the plate thats in focus?
i have a spare hoover motor that looks remarkably similar

 

[The_Yellow_Ardvark]

got a picture of the plate thats in focus?
i have a spare hoover motor that looks remarkably similar

No, but I can give you the details.
Hoover AC Motor.
HP. 1/2
Rating. Cont.
Type. 129G.B.F.
Volts. 230/240.
Cycles. 50.
Phase. 1.
Amps.3.39.
RPM. 1425.
No. 7.29308

Hope that helps.

 

[eddie49]

It spun for about 20 secs. and jammed again and started humming at me.
But This time I found something. The case has a crack on it.

Now I didn't see it before, so I don't know if that has a bearing on it.

Yes, it does have a bearing ( in ) it.

I'll get me coat ....

 

[Anguz]

mine looks squarer on the end plate
also only 1/4 horse

 

[The_Yellow_Ardvark]

I am guessing that this motor is dead.

I am also guessing that the crack was old, or the shifting and moving caused it to open up.

Either way it is not repairable, unless some one knows a way.


Thanks for the help and input. I am going motor hunting.

 

[DAPPH]

Someone with an alu tig welder might be able to repair it ?

 

[The_Yellow_Ardvark]

Maybe.
But I think the case is out off alignment.
Hence why it jams.

 

[DAPPH]

Try putting the cap on 180 degree out & only gently tighten the nuts half a turn at a time after finger tightening and gently tapping the case each time with a bit of soft wood or a very small rubber hammer .
The last drill press motor I put new bearings in would ony fit one way .. If yours does work gently nick the body & the cap when it is assembled for next times clean out .

 

[DAPPH]

Just had another thought Ardy was it lifted at the pulley ..bending the shaft a smidgeon ?

 

[The_Yellow_Ardvark]

@DAPPH

Something to consider.
I am open to ideas.

It was working hard, turning oak down.

I stopped had pi n chips and when back. Then it didn't.

In my rush to dismantle I did not mark the ends on how it was aligned.
My bad.

But looking at it, it is an old crack.
I wonder if in the past it was damaged, some "fixed it" and now after hard use it failed.

Just had a quote to replace it.
£300.

Umm Nope.