SuperMod Self-Centering Vise

Following the design of self-centering chucks for lathes, I designed this project from scratch with many test prints along the way.  The large vise can hold a maximum diameter of 3 inches (76 mm), and the small vise 2 inches (50 mm).  Note that my pictures and illustrations show the large vise.

This vise is an accessory for my swivel base.  You will need the base and mount from here: https://www.printables.com/model/1157302-supermod-helping-hand-swivel-clamp-rev3. 

You can find an up-to-date list of SuperMod designs here: https://www.printables.com/@FlyingGyroscope/collections/2284604.

Key Features

• Perfect aid for painting miniatures
  • Small vise holds 20 to 50 mm bases
  • Large vise holds 20 to 75 mm bases
• Captive jaws cannot accidentally fall out 
• Multiple tolerances for the perfect fit 

Supplies

A single screw holds the vise together and mounts it to the swivel base.

• (1) M3x30 mm, or
• (1) 4-40 x 1.25 inch

Tolerance and Fit

This project is equal parts practical print and tolerance test.  I made three sets of parts to help everyone have success.  

If you want ultimate control over fit, modify step files for the sliding jaws.  Note that plain versions exclude chamfers and fillets, making them easier to edit.  At a minimum I recommend re-adding a chamfer on the bottom face to deal with elephant's foot and re-adding a fillet to the end of the teeth to help with assembly.

Assembly 

Before you begin assembly, test fit pieces to check for smooth movement.  If you get stuck at any point, inspect Assembly_Guide.3mf to see an assembled vise.

The self-centering mechanism requires an offset tooth pattern for each sliding jaw.  You can easily identify each unique jaw by the number of stripes on the end.  Follow the pattern shown below.  Start with jaw 0 and move counterclockwise to the next slot.  Once jaws are in place, gently squeeze inward to keep them aligned for the next step.  You can use a rubber band to keep them in place.  

During assembly, there is only one orientation where the teeth and spiral ridges mesh together.  With jaws held inwards, jaw 0 should line up near the tab with a triangle marker on the bottom.

Locate the triangle marker on the bottom of the scroll plate.  Set the top plate+jaws on top of the scroll plate, and line up jaw 0 with the specially marked tab.  Rotate the plates back and forth (centered around the triangle marker) until everything meshes together.

If you could not find the mesh point, try making a few full rotations until everything slides together.  If you still cannot get the pieces to fit: (1) confirm that you have jaws in the correct order, then (2) slide all jaws out of the top plate and confirm that each one can mesh with the scroll plate.

Finally, add the base plate on the bottom to make a scroll plate sandwich.  Align the hexagon pattern on the top and bottom plates and squeeze.  You now have an assembled vise, ready for a swivel mount.

Thanks for visiting, and enjoy!