Lathe Chuck Enhancements

[akjeff]

Spent some time on a couple of things I've been meaning to do ever since buying this 8" Bison Set-Tru chuck. It's a great quality, very accurate chuck, but the key that comes with them is about useless. It's only about 3-1/2"-4" long, and if you have any large diameter parts in the chuck, it's a knuckle buster. Picked through the scraps/cut offs, and made a new one. Basically a piece of 3/4" o.d. .083" wall 4130 tube, and a couple of nubs machined out of 4140 bar, pressed and welded into each end. T-handle is 3/8" drill rod. Light, comfortable, and will clear any workpiece my 14" lathe will swing.



While the chuck was getting attention, I went ahead with drilling & tapping( 1/4-20 and .625" deep ) 9 holes in the face, so that sacrificial aluminum ferrules can be screwed to the chuck, and faced off, to aid in turning parts that require them having very parallel faces. Decided to go with the method Joe Pie demonstrated on his channel.

It was simple and quick to do. While it lacks the sophistication of ROBRENZ and Stefan's adjustable setups, this way is simple, cheap, and the parts won't know the difference.

 

[akjeff]

Had enough material left over, and made a smaller version for the 6-jaw this morning. It also had a tiny key....not much bigger than you'd find with a large drill chuck.

 

[Alcap]

I remember watching that video about drilling the chuck , Im just too scared LOL . Did you ever check the face of the chuck for being parallel ( square ) ? I guess if it is you’ll be able to just install the standoffs like you would parallels and only face them once ? I think I’m just going to give it a try !

 

[akjeff]

I remember watching that video about drilling the chuck , Im just too scared LOL . Did you ever check the face of the chuck for being parallel ( square ) ? I guess if it is you’ll be able to just install the standoffs like you would parallels and only face them once ? I think I’m just going to give it a try !

I'd be lying if I said I wasn't a little uneasy punching holes in a perfectly good chuck. There appeared to be about 3/4" of material from the face, to the scroll. So, I went with holes 5/8" deep, and finished with a bottom tap, to get as much thread engagement as I could, which is over 2 diameters for the 1/4-20 screws, which should be plenty. Very happy when the last hole was drilled, and none broke through!

Edited as I forgot to answer your question @Alcap, sorry! Yes, I've checked both the face of the chuck, and the steps on the jaws. All is good to a thou or less. Gotta love Bison chucks! Even though simply bolting on the standoffs( once they get an initial face cut ) will probably be reasonably close, I'll still give them a skim cut to be sure. To be repeatable, I'd have to number them all, as well as having a witness mark so they stay clocked in the same position every time. It'll just take a minute to true them up fresh.

 

[verbotenwhisky]

Had enough material left over, and made a smaller version for the 6-jaw this morning. It also had a tiny key....not much bigger than you'd find with a large drill chuck.
View attachment 459754
View attachment 459755

I need to make a chuck wrench for my lathe, the one(s) that came with it are short....

 

[petertha]

I made a square to hex driver for my Bison 5C collet chuck which has a very fine pinion so needs lots of turns. I use my cordless driver set with low torque.

I didn't take a picture but sketch shows I made a similar driver for my larger chuck with a hex to match a socket. So you could put it on a typical clutched cordless driver or torque wrench if that was important. The only PITA aspect was keeping the driver stub in the socket. A small magnet is an easy solution but I don't like the fur it attracts. Could probably braze or tack but not sure about the plating. I guess JB weld for that matter but kind of low brow.

 

[petertha]

@akjeff can you post a picture showing the mounted spacers/standoffs/ferrules... whatever they are called.

 

[akjeff]

@akjeff can you post a picture showing the mounted spacers/standoffs/ferrules... whatever they are called.

I'll try to remember to do that tomorrow. In the mean time, if you watch the YouTube link in the original post, it'll pretty well answer your question.

 

[petertha]

Ah sorry, I didn't realize it was an embedded YouTube vide link. I see how its done now.