Moderated and approved by: "resonance" <resonance@xxxxxxxxxxxx>The voltage isn't very high, so no use buying the expensive G-10. I've used PE and white acetyl rod (delrin) which can be easily machined to make excellent HV feedthrus. We usually put a small "shoulder" on the rod so it can be siliconed directly to the inside of your chamber. Use 2 inch dia and machine a 1/2 inch shoulder for approx 3/4 inch long. For the main wire you can use 4 AWG fine standed welding cable. Keep it in air over to the ignitron as the insulation is not designed for high voltages. Ignitron and trigger circuit set approx 12 inches outside the firing chamber.
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Dr. Resonance
I will eventually be building a containment vessel (possibly even with some sound insulation) for coin shrinking work coils, after I get my main pulser rebuilt. The chamber walls will probably be made from 1/2" steel plate with 1x1" angle iron ribs/stiffeners. The pulser stores a maximum of 18kJ @ 10kV (wish the voltage was higher). As for insulating materials for the HV feed-through area, what materials have you used? I was thinking of using two layers with an air gap, possibly with 1/2" silicone resin based G-11 on the inside. I gather the larger the chamber, and more distant the walls from the work coil, the better the survivability. I also assume that high modulus, high hardness materials like phenolic laminates will tend to shatter, even the linen based ones. What have your experiences been and what materials have you used? G-10? G-11? Polycarbonate? Phenolic? Filled polycarbonates? Delrin? - Bill "Gomez" Lemieux