Bent Motor Shaft

[500e]

Reckon the bearing is held in by plate & screws, it looks like a dimple at the top of housing where screw may be.
As you found the shaft is soft I would try the pipe over the shaft & pull, did it on a bench drill motor that was nearly as bad, 2 pulls a bit of luck & about 1.5 thou run out, what's to loose

 

[Seadog]

You could go down the Abom79 route and make a new shaft for it. You might need a biggish press to do that, though. Oh, and a working lathe and milling machine

 

[Parm]

How do you know about the majestic centre it caught on fire the other week, big news here.

I dropped it, but not from that height. Only a few metres

I don’t know anything about motors or shafts etc. But a 19mm shaft is a heft of a lump. How have you managed to bend it?

 

[Pete.]

I am officially an idiot.

I have taken apart my motor and ended up managing to drop the rotor with the end housing on the shaft, and it has bent.

Told you it wasn't man enough

 

[Dieselman 63]

Told you it wasn't man enough

Maybe I should go down the 1ph 240v-400v 3ph vfd route now...

 

[Pete.]

Maybe I should go down the 1ph 240v-400v 3ph vfd route now...

If you saw my southbend going today you wouldn't hesitate. At threading speeds I have it stopping in 1/4 turn.

 

[Dieselman 63]

If you saw my southbend going today you wouldn't hesitate. At threading speeds I have it stopping in 1/4 turn.

Yeah I’ve used a vfd before which had the e-stop, amazing stuff.

 

[Pete.]

Not e-stop, normal stop. Haven't even fitted a brakig resistor or implemented DC injection braking yet. I'm using a Yaskawa drive which has literally hundreds of parameters you can set. Half of it is too deep for me but some is really handy, like you can switch between several braking rates, very short for threading to a stop etc or more gentle for higher-speed turning so you don't spin the chuck off.

Do it - you know you want to!

 

[Carl Wilson]

Cut the bent portion off to get the bearing off. Press the shaft out from the rotor. Get a new shaft made or if you have another lathe make one.

Don't mean to be flippant. Abom79 dud something similar as the shaft of his K&T mill motor was bent.

 

[Carl Wilson]

Cut the bent portion off to get the bearing off. Press the shaft out from the rotor. Get a new shaft made or if you have another lathe make one.

Don't mean to be flippant. Abom79 dud something similar as the shaft of his K&T mill motor was bent.

 

[Screwdriver]

I am officially an idiot.

I have taken apart my motor and ended up managing to drop the rotor with the end housing on the shaft, and it has bent.

The only good news is it didn’t land on me, crack the casting or bend the rotor fins.

Now how can I get the rotor bent straight enough to take the housing off, and how do I go about straightening it? I don’t have oxy acetylene or any other means of heating it.

Depends what it's for. If it is for a specific purpose, you could bend it as straight as possible with a pipe over the end. Then turn the end down by using the motor as its own lathe. Another option would be to premanently fit a collar over the bent shaft and turn that straight. If its for a pulley, fit a blank and turn the pulley again while its on the motor.

This assumes the motor still spins...

 

[Seadog]

Don't mean to be flippant. Abom79 dud something similar as the shaft of his K&T mill motor was bent.

Post 22

 

[Pigeon_Droppings2]

Cut the bent portion off to get the bearing off.

I generally try to work out how things could get worse....which generally happens when I try to fix stuff.

I'd be tempted to sacrifice the shaft too to save the rest of it?

 

[Carl Wilson]

Normally when something like this happens you have to take fairly drastic action to make progress.

Realistically you are not going to straighten a shaft to any level of accuracy to enable it to run at 1500 rpm or thereabouts without it causing further damage along the line. Sooner rather than later.

 

[Pete.]

I'm of the opposite opinion to Carl. I see no reason why that shaft could not be pressed straight, at least as straight as your average lathe pulley would run. 1500rpm isn't all that fast and it only has a small pulley on it anyway. Pull the bearing and bore a solid block to sit in it's place. Stick it in a press and shove the bent end down. Use a dial gauge to measure the runout and the amount you press it.

 

[Dieselman 63]

There is no bearing. The housing is machined and oil soaked wool is packed inside. I’ve never come across a motor like this before.

 

[Seadog]

That looks like someone left a syrup in the housing

 

[Pete.]

Was that motor used by Burt Munro?

 

[roofman]

There is no bearing. The housing is machined and oil soaked wool is packed inside. I’ve never come across a motor like this before.

thats why factorys burn down

 

[roofman]

That looks like someone left a syrup in the housing