Polishing the ground plate

Did some polishing last weekend, here is picture of the ground plate, nice and shiny:

The ground plate will have two 1-pole, two 8-pole and one 4-pole feedthrough.
Also tried to fix the mass spectrometer, still have the problem that after bake-out all the QMG064 sensors fail.
I tried to clean the grid with fine quartz powder and ultrasound cleaning, no effect at all..... to be continued.

Vacuum feedthrough

The old and big second hand pillar drill works great! Although drilling a 40mm (for the viewport) hole through 20mm aluminum does make the 800W motor a bit warm.
I've also mounted 2 times high voltage (20kV) feedthrough for the octavio core, one 4-pole mid-voltage (4kV) feedthrough for the focus coils. Still have to mount two times low voltage 8-pole feedthrough for the electron guns.
For the current through the core I will use batteries, the batteries can have the same potential (+12kV) as the core, this will simplify building the octavio core.