Preliminary Tests
IEC conductivity tests
In putting all the components together, we step-by-step tested multiple components in conjunction. First, we tested if the IEC built in Part 3 was conductive and the screw junction was stable enough for a steady flow of electricity. (left)
Rectifier
Next, we constructed a simple bridge rectifier using four 20kv graded diodes assembled in a square. To the left, you can see a quick preliminary test on the breadboard in which 25VAC was converted in DC to steadily light up the blue LED diode. After this successful test, the diodes were soldered together with high-voltage wires. A secondary test was done (below) in which the AC current from the Neon-Sign Transformer (NST) is converted into DC and steadily lights up the yellow LED diode.
The rectifier system was then put into a 3D printed box, filled with cooling oil in order to prevent overheating, potential arcing, and for ease of transportation. (below)
High Voltage Intake
We needed a way to place the IEC in the direct center of the vacuum chamber while also providing a sealed way of creating a voltage intake. To do this, we 3D printed a stand (CAD shown to the right) that the IEC would sit on top of and a wire could feed through into the chamber.
We stripped then fed a wire through the hole, and used a heat shrink to attach the IEC to the top of the stand seen above. It was at this point that we remembered that 3D printed parts are not very good at preventing gas-penetration. The plastic is printed in rows and between each row is a gap in which gas could flow in and out, thus we decided to do cover everything in JB-Weld, a classic solution. JB-Weld still outgasses -- releases trapped gas once put under high enough pressure -- but to a much better extent compared to 3D printed parts. In the picture to the bottom left, the initial set up is pictured upside down as it is prepped for epoxy, and to the bottom right, there is a (albeit blurry) photo of the final dried epoxy as seen from above.
Tests
After putting all components together, we achieved clear plasma! While the neutron emission and radiation is negligible, so far, with 12kv and a 1500 microns of pressure, we have a stable proof of concept.
After reapplying some of the teflon connections and additional layers of epoxy, we were able to decrease the pressure to 700 microns, creating a substantial increase in plasma:
Mark 1 fusor is complete! The full set up is below. Our next steps are to create a deuterium intake, redesign the chamber in order to accommodate x-ray radation, incorporate a neutron emission measuring system, as well as upgrade existing voltage and vacuum systems.
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