I will eventually break this tube (implosions! I know!) and use the electron gun and phosphor inside the vacuum chamber.

The idea is to run the sydney experiment with a pure electron beam. We are currently using an air or deuterium plasma.

Before I break the CRT I will operate it in tact. Here is the pinout for 3BP1.

This sweet CRT hack is a good start for the power supply needs.

Already got the hot cathode running:

On the 3D printing front I received the 3D printed ceramic coffee cup I ordered last month:

It looks really promising. Soon we’ll have a 3D printed ceramic magrid.

Made this image by mistake:

UPDATE: Progress towards a coil former with integrated electron gun:

UPDATE:

More progress on this design… can you see it evolve?

You can see the faceting produced by the chosen resolution. Looks like we are back in business with designing and producing Polywell cores.

Going to try and hack my way around the problem today, so we can order the first core prototype.

The sketchup-svg-outline-plugin is great for producing laser cuts for Ponoko. I recommend this sketch-svg tutorial.

Added the trapped nut cutouts:

This intersect model tutorial was essential for making the trapped nut cutouts.

I just ordered v1 of the extruder from ponoko:

This iteration of the design is nearly ready for rapid prototyping. The chassis walls are thicker, and there is more room for the coils. Also the joints are hollow now, so the coils can be wired together. Specs:

• outside_radius: 242.487113059643 mm
• torus_midplane_radius: 192.693468865964 mm
• donut_exterier_radius: 107.8 mm
• torus_radius: 77.0 mm
• donut_hole_radius: 46.2 mm
• torus_tube_radius: 30.8 mm
• torus_tube_hollow_radius: 25.564 mm
• joint_radius: 21.56 mm
• joint_negative_radius: 7.546 mm
• torus_tube_wall_thickness: 5.236 mm

Here is the corresponding array of 12 lids:

Now we can export to an STL file, and produce our first physical object (in plastic to begin with).

this is what it would look like before inserting the coils.

here is a closeup:

I created this using ruby to pass draw instructions to mged (the main command line tool for BRL-CAD):

require 'matrix'
phi = (1+Math.sqrt(5))/2
icosahedron = Matrix[
[0, +1, +phi],
[0, +1, -phi],
[0, -1, +phi],
[0, -1, -phi],
[+1, +phi, 0],
[+1, -phi, 0],
[-1, +phi, 0],
[-1, -phi, 0],
[+phi, 0, +1],
[+phi, 0, -1],
[-phi, 0, +1],
[-phi, 0, -1]
]

icosahedron.row_vectors().each_with_index do |v,index|
`/usr/brlcad/bin/mged -f -c test3.g 'in torus#{index}.s tor #{v[0]} #{v[1]} #{v[2]} #{v[0]} #{v[1]} #{v[2]} 1.0 0.125'`
end


This basically iterates through the vertices of the icosahedron, and draws a torus normal to the origin. Now we are tantalizingly close to having a CAD file we can render in metal.