Cloud chamber for cosmic ray research

In 1948 war-built V2 rockets with nitrogen gas operated Wilson cloud chambers were used as a major tool in cosmic ray research:

From July 1948 edition of Popular Science

Reading this article, the idea was born to build a much smaller Wilson cloud chamber, operated by compressed  CO₂, and launch it on a weather balloon or experimental rocket:

I built a first prototype. The PCB in the front is the HV source for electrostatic clearing field. The chamber is illuminated by a line laser. The alpha particle source is Am241.

This video shows the operation of the chamber:

I made 3-D-drawings with Google Sketchup and my friend Russell helped me to manufacture all the parts.

Unfortunately the choosen PMAA pipe cracked as soon as it got in contact with isopropyl alcohol (solvent crazing). The project is now on hold. I have to go on some day.