I have been working on the new electron gun for the last months. I have designed and built the new version with many improvements.
I achieved a 0.1mm spot size in the center of the working area. This is very good news for printing fine details in metal parts.
This 0.1mm focus test was very useful to understand the need for a stable HV power supply. With my HV power supply, small changes in the mains AC input translate to changes in the HV output and focus spot size.
So is a good idea to test a commercial HV power supply or add some kind of feedback control to the Cockcroft Walton multiplier.
This was one of the most difficult technical parts. There are still many challenges to solve, but this was a big step.
Please remember to support me to continue working on this project. I'm waiting some financial support to release the designs and schematics. Many thanks for your help!