I've laid out this 4 inch PVC pipe and drilled holes to line up with the slots in the stainless steel plates. This way I can bolt the plates inside the tube using the stainless steel bolts as electrodes where I will connect the electrical supply. By threading these holes I can more easily pull the plates back against the inside of the PVC tube and seal them more easily air-tight. The other unit to the left is my previous unit where I studied how to make this work better.

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