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I Need Ideas-New Electric Motor-Different Shaft for Pulley Mount

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I purchased a replacement motor from Graingers for my band saw refurbish.
1947 Delta 14" band saw gets a new power plant.
The old motor has a 1/2" shaft with a flat for the allen bolt to mount.
The new motor has a 5/8" shaft with a key way.
Should I bore out the pulley?
Can I buy one that fits?
What would you do?
Thank you for your help.



Unless it's a totally oddball size I think I'd just get a new pulley. Sure you could enlarge the hole in existing one, but that still won't give you a key way in the pulley to match the key way in the new motor shaft. You'd either have to cut a key way, make a half-depth key, or continue to use the set screw by itself. Seems a lot of compromises when a new pulley isn't that expensive. Just my thinking.

I would bore and single point broach it with a boring bar. I know that I could have it done in less time that what it would take to get to the hardware store. Besides that, it would probably be truer than a store bought pulley.
Mr. Derek, I bow to your confidence. A single point broach is a new term to me.
I’ll see what I can find on that subject.
I agree the quality of my 70 year old pulley can not be duplicated today.
I would go to Grainger and turn it in for one that will fit the way you need it to. They are good about taking in returns...
I just spent some time looking for a general purpose 56 frame for belt driven machinery etc. it seems 5/8 is now the standard. 1/2” is kind of puny.
Simple solution would be, find a pulley or call Grainger and ask for help sourcing the right motor.
Hmmm, I have to go to the big city of Chico today, maybe I can find a pulley.
These fractional hp pulleys must be pretty standard.
McMaster Carr or Grainger should have the correct pulley. Boring out the old one and broaching the keyway sounds like more fun!
I would just buy a new cast iron pulley. If it was a step pulley like they used on the wood/metal saw I might consider boring it out because Delta used unique spacing and step sizes. They new cast iron pulleys that I have purchased from "Surplus Center" are pretty good. In sizes like that they are less that $10 (plus shipping). Below is a link for a 2" (when used with 1/2" belt) but they have other sizes.

Hi Guys,

It might be worth checking that the new motor has a straight shaft ! I've just returned a motor with a 20 mm diameter shaft because it was bent.
A fraction over 5 thou runout on the end. Best bit there wasn't any center in either end of the motor shaft. It looked as if the ends had been machined off.
Clueless, I bought a pulley from Ace. $10.
Problem solved.
The table is going back together. I have the table on 180 out in the pic.
It is going on Craigslist next week.
Had the same problem I did not want to drill out the pully ,plus the shaft on the motor was a little too short.........went to the lathe made a "extension for the shaft" 1/2 inch female with grub screw to secure it to the small shaft, 5/8 shaft on the other end [milled a flat spot for the pully screw] and made it long enough to level the belts between pulls........simple fix works great!
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