Rebuilding a Lathe Chuck
If you are trying to rebuild a lathe chuck, it’s important to be patient and careful. Although all the parts of your chuck should be completely replaceable, they are often expensive and require precise handling to keep intact.
The instructions in this article are given for an Albrecht drill chuck. Other chucks may vary slightly in design but should remain similar in principal.
For rebuilding any kind of chuck, the first thing you need to do is dismantle it. This can prove difficult with some chucks because the hood can be hard to grab onto and may be secured very tightly. Consider clamping the chuck in a stationary position or putting it on your lathe to hold it still. You may also want to clean the exterior to make it easier to take apart.
Before you try to remove the hood, first take off the collar, which should be attached with a locking screw. Unscrew it with a screwdriver that will reach all the way into the slot so you don’t damage the screw, and simply pull the collar off the tail of the body. The collar screw is usually secured very tightly, so it may take a little work to get it out. It is good to have your chuck held stationary, in a position that allows you to go straight in with your screwdriver for the most leverage.
Now you will work on removing the hood. The recommended tool for this job is a strap wrench, but whatever you use, you will want to be careful to avoid anything metal because it will tear up the chuck.
Once you have the hood removed, turn the portion of the body you removed the collar from to raise the spindle up about half way and remove the jaws. Continue to raise the spindle until you can lift the shell off the jaw guide. Now remove the spindle, the body and the ball-bearings (without dropping or losing them!), and then remove the arbor, which should be visible through the backside of the body.
Cleaning and Examination
Use a degreaser to clean the parts of your chuck before washing them in soap and water. Air or blow dry the parts before reassembling them. Do not put the chuck back together if any of the parts are still wet. Wipe the spindle and body down with lacquer thinner to remove any residue.
Identify any damaged or broken parts and replace them. You can use a diamond file to remove any nicks in the surface.
Examine the inside of the hood. This should be textured. If necessary, use a high-grit sandpaper to create a texture for the jaws to ride on. Oil the parts lightly with a Q-tip before or during reassembly.
Put the chuck back together in the opposite order of how you took it apart. Replace the bearings (there should be 25), and put the spindle back in. Slide the jaw guide into place with the drive pin lined up. The spindle should be halfway raised in order to replace the jaws. Screw the hood back on and tighten it just until snug with your strap wrench. Open the collar by sliding a screwdriver into the slot. Replace the collar and the locking screw.
Congratulations! Your chuck is officially rebuilt. You should now have a better understanding of its inner w