Self-Centering 48mm Chuck for Mini Lathe

Originally made for cheap tiny lathes like those sold on Amazon (like so). 

Remixed from mdkendall's excellent design that provided the basis for this smaller version.

Thanks mdkendall!

This version mini-fies the design to:

1. work within my lathe's 50mm working volume (this chuck is 48mm across)
2. be able to use commonly available m3x10 screws, rather than Tommy bars for tightening
3. provide some additional mechanical support to increase rigidity

You can use this to hold on to nearly any round object up to approximately 40mm in diameter. 

Takes 4x m3 screws of either 10 or 12mm length, and one m3 nut. 

The screw and nut are installed in housing.stl, and serve as a good clamping spot for the chuck that comes onto the lathe. The alignmentShealth.stl part provides some additional support for the chuck, and should press-fit in. 

The remaining 3 screws are for the scroll plate, which can be used to lock the jaws in place once the piece is set. The other holes on the housing are for a hex key to lever the chuck closed together with the 3 setscrews. 

All parts are printable without support material, though the sheath and jaws could benefit from a 2.5mm brim if you need some more bed adhesion. 

More tips from the source: 

"After printing clean up the parts and test their fit. If there are any tight spots in the fit of the jaws in the slots, or the jaw teeth in the scroll plate, clean up with a needle file as necessary. There is 0.2mm clearance in the model for all parts that must fit together so there should not be any problem.

Fit the scroll plate to the housing and clip the circlip over the shaft to secure it. Turn the scroll plate so the leading tip of scroll is just about to appear in one of the slots. Feed in jaw A, large end first, and turn the scroll plate to capture it. Repeat with jaw B in the next slot, then jaw C in the next.

The three self-centering jaws are reversible to allow holding larger work pieces. To fit them reversed, insert them in to the slots in the order A-B-C. To fit them in the normal orientation, as shown in the photos,, insert them in the order C-B-A."

Also, it's recommended to paste some sand paper in the jaws if you need a better grip on your material. 

If jaws “stickiness” becomes an issue, make sure you have the jaws in the correct order, and try working the mechanism back and forth to break in the assembly.