Tapered key machined into arbor on Craftsman saw?

[Chris S]

Hey guys,

I got another question about the old Craftsman saw that I have. I picked up a couple of machined pulleys from a local vendor. The one for the motor fits nicely. When I try to put the one on the arbor, it won't go on very far. It looks like the key is machined into the arbor and it's tapered. Is this the case? I was thinking of filing the key down to fit the pulley on. Does this sound like a good idea? Again, this is a $50 investment, so I'm limiting the money I put into it. It's model # 113.298151.

[toolguy1000]

i have what appears to be the guts of a saw like that. the machined pulley on the arbor has a regular non-tapered key, as does the motor. the keys are independent items and are not part of the arbor or motor shafts.



have you tried grabbing the keys with pliers and pulling on them? that's how i removed the keys on my saw once the pulleys are removed.

[LCHIEN]

usually keys are cut from rectangular or square bar stock.There's usually a slot in the shaft and a slot in the pulley each just a bit more deep than about half the height of the key.
The keys are removable. Lot easier to cut a slot in a round bar and to cut a slot in a ID of a pulley than leave a key by machining away everything from a bar that isn't a key.

You should be able to remove and clean the key. New keys are available in the bins at Lowes, HD, or Ace.

P.S. maybe instead of a stopped slot on the arbor shaft they cut a ramped slot where the main part of the slot is flat but the end is ramped up to meet the shaft. If this is the case then maybe the key was pushed onto the ramp a bit making the key top appear to be tapered.

[Chris S]

I just looked at it again, and it sure does look like the key is machine into the shaft, and is tapered. As you can see in one of the pics, there isn't even any signs of a slot at the end of the shaft at all.

[Skaning]

I'm guessing a half round key. Think of the manufacturing process. How would you turn a shaft like that on a lathe. But the two ways to make a keyway is to mill it as a rectangular slot with an end mill or come down with a rotary cutter.

[Chris S]

I'm guessing a half round key. Think of the manufacturing process. How would you turn a shaft like that on a lathe. But the two ways to make a keyway is to mill it as a rectangular slot with an end mill or come down with a rotary cutter.

Winner, Winner, Chicken Dinner! I have only messed around with shafts that had a long slots. You talking about the rotary cutter made perfect sense. The key was just offset a little bit in the slot, making it appear tapered. I tapped on it a bit with a hammer and drift, and out it came. Thanks Skaning!

[Pappy]

Also called a Woodruff key. The rounded bottom make it easy to get them in slightly crooked.