Delta 14" bandsaw replacing the lower wheel

[paul handley]

I took both wheels off to replace the upper and lower tires. wheels came off easily and to top wheel was replaced just as easily. I have a problem with the lower wheel though. The shaft has a key slot that accepts a half circle key.

I put the wheel just on the shaft and align the keyway on the hub of the wheel with the key and slip it further on the shaft. But then it stops because the key turns in the slot and prevents the wheel from moving any further on the shaft.

This is the first time I have encountered this type of key and I can't figure out how to proceed. I have tried to push the key back level but it won't go. It's very tight down there and dark. even with a light I can't see much.

Does anyone have any tips that will let me put the wheel back on?
Thanks,
Paul

[Lee Schierer]

I always hold the free end of the key down as I slide the pulley onto the shaft. You can tap the key back to level with a screw driver and hammer if you can reach it. Don't beat on it, it should move easily. A little oil in the slot on your wheel wouldn't hurt.

[paul handley]

Thanks, Lee! Well I was a Swabby also, but back in the late 50's. Well I did it! It was a tight space, about like working in the wheelwell of C130, and very little illumination,. I pushed on the wheel and just moved it past the front of the key. The key immediately rose up on the back end and I took a wooden dowel and gave it the lightest of taps and pushed on the wheel. Voila! It pushed right on!

I can't understand why that semicircular key would be better than a rectangular key in a milled slot that went from the end to about an inch in. Seems like it would make it easier to assemble. I understand the need for the key since it's the driving wheel, but, Oh. well...

[John K Jordan]

I can't understand why that semicircular key would be better than a rectangular key in a milled slot that went from the end to about an inch in. Seems like it would make it easier to assemble. I understand the need for the key since it's the driving wheel, but, Oh. well...

I always thought they were used because the semicircles were quicker to cut - straight in with a circular cutter instead of cutting a longer slot. And once in place, they certainly can't go anywhere such as slip out the end of a slot! But I'm not a machinist (except in my own mind when playing in the back room of my shop. )

I usually try to hold the back end with pliers but I have had to tap on them before.

JKJ

[Lee Schierer]

I can't understand why that semicircular key would be better than a rectangular key in a milled slot that went from the end to about an inch in. Seems like it would make it easier to assemble.

What you have is called a Woodruff key. From Wikipedia: "The circular segment can be cut directly by plunge cutting with a circular Woodruff cutter without any reliefs. The main advantage of the Woodruff key is the elimination of milling near shaft shoulders, where stress concentrations, and concentricity would be affected. The latter is particularly important for high speed operation. The more exact fit of the key and key way also reduces play, and stress concentrations in, and improves the reliability of the key. An additional advantage is a stuck key can be removed from a shaft with a hammer blow, the circular profile will push the key out of the slot, as opposed to a standard key which will need to be pushed axially, or pulled out of its slot."

[paul handley]

Thanks again about the woodruff key. I remember now having heard of it but I didn't know all those particulars.

And thanks every one for posting! My 2 bandsaws are both over 40 years old an originally purchased by me. Pretty good life for a Craftsman and a Delta huh?