I bought a Webster lathe the other day. It's in great shape and I'm happy with it, but it came with a jacobs chuck without the key. The chuck spins so the jaws open and close but I don't know how to get the entire thing off if I want to change it out or service the lathe. I actually don't even understand why the chuck spins. Shouldn't I need a key for that too? I don't want to force anything and break it so I'll wait for some advice.

Anything I say here is based on experience with a drill press.

The chuck should spin by hand and the key is for the final tightening.

The initial install of the chuck just involves sliding it up on to a tapered shaft then giving it a rap or to with a rubber or wooden mallet for a fraction fit.

Removal requires a specialty tool, two tapered U shaped wedges that you slide together till snug then tap with two hammers till the friction it overcome and the chuck is loose.

Again, all wood working drill press experience.

Ok thanks. Now I at least understand the key component. I'll have to find a picture of the u shaped wedges to understand that part.

Dale-
The chuck should be mounted on a "WW" arbor. Loosen the drawbar, and it should come right off, still attached to the arbor. If the chuck is a Jacobs, there will be a number on it; 0, 1, 2,etc., and you can get a replacement key from a well-stocked hardware store or machinist's supply. Don''t separate the chuck from its arbor unless you are going to replace it with another chuck.
Regards,

Bob

On some hand drills, when you open the jaws there is a screw. worth a look.

Shims/Wedges

Picture is worth 1K word
The ol Morse taper.
The machinists like Lorne may chime in.

Thanks everyone!

It's a great lathe. No one else bid on it on eBay the night I bought it. Still can't figure out why. A really shiny Peerless went for 334 bucks and this was less than half the price. It wasn't as shiny but came with the motor, attached to a board with a switch. Works beautifully. I took some 0000 steel wool to it and gave it a little love and it's looking sweet.