FUSOR II

FUSOR II

Author: Jay, Jimbo, Scott & Tim

Growing upon what we learned from FUSOR-I, and a happy windfall of surplus vacuum hardware our group set out to build the Fusor of all Fusors, at least at the amateur level. It works! However, bigger is not always better. The larger chamber diameter limits the radial electric field, reducing the amount of-self ionization. However, the extra space the larger chamber provides is perfect for testing ion sources.

This machine was built by contributions from many friends. This system continues to evolve as we test new diagnostics. Please check in periodically for updates.

FUSOR II, also know as MATER-I, our Fusor for testing materials, diagnostics, and ion source concepts in the pursuit of IEC fusion.
We purchased the chamber from a surplus sale of industrial equipment.
Took it home and cleaned it up. Miraculously all the knife-edge seals were in tact.
Tim built a small 80/20 stand to mount the chamber too. Jay and Scott started bolting it up with mostly blank flanges to begin with.
The bottom flange was a copper wire seal, that new cost $90. We were able to reuse one. It holds fantastic vacuum and we will never unbolt that flange!
All buttoned up for vacuum testing.
Leak checking with the wonderful Varian 979 Helium leak checker given to us by our friend Jim.
Passing the vacuum test, Tim installed the first grid. Note that two of the horizontal ports are outfitted with load-lock doors to make accessing the fusor internals easy.
First light!
A sequence of star mode like images were taken, this one is particularly beautiful.
The FUSOR-II deserved its own room, so we constructed one of sold concrete blocks, mostly to keep its operators away from the HV and associated hazards. The walls are double thick for structural integrity while self-standing.
The window is leaded acrylic with 8mm Pb equivalent.
The completed room.
Star mode.
Definitely getting warm, the grid is glowing. We learned our lesson with FUSOR I.
Indium foil.
Placement of indium foil in polyethylene blocks
1 hour HPGe count indicates indium activation.
Note our calibrated He3 neutron detector on the left. So far, our record is only 500k neutrons / second.