Shortening a motor shaft

[Jim F]

What is the preferred method to shorten the shaft on a motor ?
I have a 1/2 HP Marathon dual voltage I just got. Set-up as a redneck buffer, but may put it to better use.
Has a 1" shaft that has been turned down to 1/2" at the end.
There is 11 1/2" of shaft out of the body.

 

[markba633csi]

A hacksaw with a good blade will usually cut it with minimal effort
-Mark

 

[tq60]

Hack saw works...

If you have a mill you ca cut with hack saw, place on mill table andwth motor running bring In an end mill from end to true up end.

Or place on lathe bed strapped down and use lathe tools to true it up, visualise the motor as head stock and turning shaft as spindle.

No lathe or mill, angle grinder touching end of running motor shaft.

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[Dabbler]

-- are you just taking the 1/2" part off, or going shorter?

 

[rwm]

After you cut it, touch it up with an angle grinder while the shaft is turning.
Robert

 

[Jim F]

-- are you just taking the 1/2" part off, or going shorter?

Not sure , but I don't think I need almost 12" of shaft.........

 

[Jim F]

Hack saw works...

If you have a mill you ca cut with hack saw, place on mill table andwth motor running bring In an end mill from end to true up end.

Or place on lathe bed strapped down and use lathe tools to true it up, visualise the motor as head stock and turning shaft as spindle.

No lathe or mill, angle grinder touching end of running motor shaft.

Sent from my SAMSUNG-SM-G930A using Tapatalk

I have a lathe and a mill.

 

[rwm]

Could you chuck up the shaft in the lathe and spin it with the motor body strapped down? That would allow you to turn the shaft to a specific size and thread it. I have always wondered about this and whether it could damage the windings? I'm sure the bearings would be fine. Can any motor experts weigh in please.
Robert

 

[Jim F]

Could you chuck up the shaft in the lathe and spin it with the motor body strapped down? That would allow you to turn the shaft to a specific size and thread it. I have always wondered about this and whether it could damage the windings? I'm sure the bearings would be fine. Can any motor experts weigh in please.
Robert

That is what I was thinking, versus pulling the rotor out.
I do know that if you turn a large 3 phase fast enough, it turns into a generator.

 

[benmychree]

That is what I was thinking, versus pulling the rotor out.
I do know that if you turn a large 3 phase fast enough, it turns into a generator.

That may be true, but I think only if power is applied into the motor, then it will "push back" One of my friends did this with relatively small hydro electric installations with Pelton type water wheels.