Just Picked Up A Kent 4vk

I'll pull the motor apart today and take a good look at it. If the shaft comes out, I think it would be much easier to just make a new one rather than trying to weld and machine it.

What material would be best for a new shaft? 4140?
 
Any of you electric motor guys want to jump in here? This is getting outside of my experience. I would think that 1018 shafting would work, but not sure.
 
Got the top plate off the motor. Found that the fan had no set screw in it to lock it to the shaft, and has 2 blades missing.

I put it in my 20 ton press and there is no way I can press the shaft out. Just don't have enough tonnage to move it.

I've looked for a motor repair place that may be open today but no luck. Will have to be next Friday before I can take it somewhere.



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We can try it in my 50 ton press, but I don't know how those shafts are actually put in. I guess that the worst that could happen it that the armature would be totally destroyed.:chemist:
 
I'm thinking of taking it to a local motor repair place in Vancouver I just found. Hopefully they don't close before 5 on Monday. They may be able to tell me something about it and if the shaft can be pressed out.

I contacted HH Roberts machinery repair and they want to sell me a new electronic drive head for $4k. Kinda pricey for a $1000 mill I think. They didn't even offer me a standard replacement motor.

http://www.hhrobertsmachinery.com/replacement-milling-heads.html
 
can you not weld it up and then turn the whole thing between centers? That's how I've seen some people do it online. Weld it oversize in small goes then needle it as you turn it down? Alternatively, I've also read of people cutting of mullered shafts like that and then press/ pinning in a new shaft, with final dimensioning between centers to make sure everything is lined up. I couldn't imagine that either of those approaches would be beyond the abilities of either of you :)
 
I have the armature out now. Wasn't easy getting the top pulley off it without breaking it.

I had to extend my draw bar on the Shizouka because it was too short and only grabbed 1/4 on the tool holder. I drilled and tapped the original bar and extended it with some high strength threaded rod. Worked out pretty well. Was thinking of doing that with the motor shaft, but I just ran a file across it. Slid off like it was on ice. Not a mark on the shaft. Hard as a rock. So that idea is out.

I think the only option to try and repair the damage is to make a new shaft. I can see what direction the armature is pressed onto the shaft. I'm gong to try and make some blocks to put under the armature and see if I can press the shaft out. I don't have much to lose by trying.

The shaft has 3 key ways milled into it. Odd I think.

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Well with a direct press on the armature with my HF press the shaft wouldn't budge. It's really on there.

I looked closer at the fan blade and several of the blades are bent, and again 2 are missing.

Have to think about plan B now.
 
wow, they really neglected that one. I wonder if the multiple keyways were attempts to fix the problem multiple times. If so, you would have thought they'd learn their lesson the first time!
 
Just have Abom flame spray some material back on and remake the keyway :)
 
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