Vacuum system update

When the lab where I work got a decommissioned Scanning Electron Microscope I got back into vacuum systems while bringing it back to working state. A while ago I got some high vacuum parts from a mass spectrometer. To create a platform for doing High Vacuum experiments I wanted to build this:

A removable vacuum chamber is sealed to a metal table with a rubber gasket. A Turbo pump and a high vacuum ionization gauge are sealed to the underside of the table with ports connecting to the chamber. A port with electrical feed-troughs would allow connection to the experiments inside the chamber.

Made this setup:

First render

I used the table from an old overhead projector to hold all the equipment.

For easy access I wanted the vacuum chamber itself to be a bell jar. I didn’t have one so I found a 4000ml reaction vessel which I for a start find to be a reasonable volume. A 4mm. steel plate serves as the table top and the bell jar is sealed to the surface with a simple gasket cut from 1mm rubber sheet.

Since the bell jar I had only had a 140 mm clearance I needed to fit all the ports to the chamber within this area:

The base plate is cut from 4 mm. Iron plate (this later turned out to be a bit thin).

Welding template

I cut a welsing template to help position all the bits for holding various parts of the system.

After cleaning the pump gauge and feed through was mounted.

Feedthroughs was made from brass post soldered to circuit board clamped to the table with rubber seals.

The control electronics was mounted on a shelf under the table and the control panel mounted on a front plate.

Front panel for controls

Various power supplies and instruments mounted in front panel:

Filament voltage augmentation unit

Vacuum controller and feedthrough mounted
Feedthrough access panel
Ion gauge and feedthrough

 

 

I decided to buy a new bell jar and a colleague thought it needed 3D printed cheese..

All in all I’m very pleased with the result. All the major parts of the system has been built and tested and I have pretty much stuck to the original design. I am now able to place experiments in high vacuum with relative ease and interact with these via. the feedthroughs.

 

 

 

 

 

 

 

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