Star in Cube
In the Atlas of Bergeron's Manuel du Tourneur, there's a star in a cube that's rather unique. It's on page XX and it's figure 3. What's unique about this piece is that the star is larger than the dimensions of the cube. I assume that it was turned from a sphere, thus the points of the star stand proud of the flat surface of the cube, but tangental to the corners of the cube.
Tools & Supplies
You'll need a couple custom tools for this one. Details to come.
You'll also need 5 styrofoam plugs 2" in diameter and 3/8" thick with a 1" round lower stub and 1/8" hole in the center. See image at right.
You'll need a very round ball for this project. No wobbly ball will do. Start by determining 6 points on the ball. Then, at each point, make 3 circles with diameters of 1/8", 1/2" and 1-1/8". The smallest circle will be the point on the star, the middle circle will be the hole in the cube and the largest circle will be the flat of the outside of the cube.
Here's the process for making this one:
- Line up the first end grain point in the chuck. It's critical to do the 2 end grain points first on this project.
- Using a square end tool, about 3/16" wide, remove the stock between the first and second circle to a depth of 3/4". This defines the point of the star and the hole that goes through the cube.
- Make the undercut with the custom hollowing tool. This operation produces the outermost hollow inside of the cube.
- Remove the larger circle. This should be about 3/8" below the top of the point of the star.
- Remove the waste inside the hollow to the surface of the inner flat that makes up the base of the star.
- Carefully shape the 1/4" protrusion into a spike.
- Perform all sanding necessary, as you're now done with this section and it won't be held stable and available for working again.
- Insert the styrofoam plug into the hole being careful to fit the spike into the hole in the plug.
- Spin up the lathe and shape the plug to the contour of the ball.
- Perform these same operations on the opposite end grain point.
- Work the remaining 4 points.
- Remove the ball from the chuck, take out the plugs and admire your recreation of Bergeron's wonderful item.