Repairing a broken stepper motor

[+Graham]

A friend of mine asked me to take a look at his NEQ6 mount as it was making a horrible noise and the RA axis had stopped working.

After stripping down the mount I could find nothing wrong.

 

Once re assembled I tested it and sure enough the RA did not move and it was making the most terrible racket.

 

Thinking it was the belt I pulled the RA motor out to check the gears.

They were all fine as was the belt.

 

This is most weird I thought to my self. ?

 

I ran the motor up on the bench to see what was what and found the drive shaft was not moving .

Stripping the motor down I found that the drive shaft had sheared completely in half just below the front bearing.

 

 

That's a new one on me I thought as I stared at the shaft in disbelief. ?

 

What to do.

After a bit of fudging I managed to remove the broken shaft from the twin rotors of the motor.

 

Using the two broken halves of the shaft I managed to get all the dimensions I needed to make another one.

 

This I duly did at work on Friday .

 

This morning I fitted the new shaft and re assembled the motor.

Setting it back up on the bench I tried it. ------ Nothing not a hint of movement. ?

 

Not one to give up on anything I did a bit of research online to find the correct orientation for each of the 2 central rotors.

It turns out I had set them up 1/2 a phase out of alignment with each other.

Once I had reset the rotors I ran the motor up on the end of a drill for half an hour to free everything up and to align all the bits to the new shaft.

This is the result.

 

 

I love it when a plan comes together. ?

[Bottletopburly]

Graham you are a genius ?

[+Graham]

I don't know about that ?

[BAZ]

That is above and beyond mate, excellent repair.

[+RonC]

Great repair Graham (as usual!) 👍