stuck chuck

Plain #36 or are there some extra letters or numbers with it? #36 should be #3 Jacobs taper, but additional identifiers might point to locking screws or something similar. Looking down inside the jaws, you don't see a screw head, do you? If there are any other letters or numbers, you might check with Jacobs to see what they mean.

For a simple Jacobs taper, the wedges should work. Unless there is not enough of a shoulder on the arbor, in which case you can drill a hole crosswise through the arbor and put a pin through for the wedges to bear on.

John Martin

I recently tried to remove the JT3 arbor from a Jacobs BB super chuck. I used wedges and drove them on so hard that the Jacobs arbor deformed where the wedges contacted it. I used a punch through the center of the chuck to drive the arbor out while the wedges were still inplace. It came apart with a big bang because the wedges were pulling so hard. It looked like the chuck had spun on the arbor and galled it just enough to bind up real tight.

some chucks have a hole in the back so you can drive the arbor out.

Thanks, John. Yes, the chuck is a plain #36 - no other letters or numbers. There's no screw visible if I look down through the jaws. The shoulder on the arbor is big enough to use wedges. I squeezed a set in so hard that both the wedges and the arbor deformed.

open the jaws and drill something like a 3/8 hole through the bottom of the chuck body.You will see the top of the arbor through the hole. Then put a