UV resin didn't work to fix the shaft, it was fairly easy to remove it once cured. The resin the shaft is made of seems to be rather "special".
I then started making a mold using alginate. This worked, but since the mold releases water all the time neither UV curing resin nor epoxy felt happy with that and the casted shafts looked like a mess. What I learned in the process: Forget alginate as a solution for a mold, it simply doesn't work out.
Already ordered some RTV silicone (
https://www.silikonfabrik.de/silikone/silixon/silixon40-silikonkautschuk-rtv2-giesssilikon.html?number=SILIXON40-500-0709), but wanted to finish the project this weekend. I remembered to have some RTV blue silicone and took that to make a mold. This works to some extend as it is not that liquid. However, it takes 24 h for it to cure, so this also would have been a "finish the project this weekend" blocker.
Eventually, I looked inside a Fluke 8000A I had sitting in the shelf and to my surprise found the very same switches. So for the time being the Fluke 8000A had to serve as a donor for the shaft and the springs until I have made and organized replacements. I also removed the lock on the Mean switch and replaced it with a spring.
The unit is mostly back together and I could turn it on without having to fear something goes up in smoke and yes, she is working
There is still some work to do before I can call it finished, but I'm close to aquire some data like noise, short-term and mid-term stability.
-branadic-