Nice job PhilippF, I've had the same idea and I'm using a vacuum oven for my prototype evaps. It's not my original idea really, I'm an automotive engineer and all production automotive evaps are either controlled atmosphere or vacuum brazed. Cleaning evaps after they are brazed is just such a drag... Wonderful to have them ready to go when they cool

I started out with making brazing rings from sil-phos-copper alloys, but now I'm using a paste that let's me control the alloy placement much better. What are you using?