It was not easy, it was not fast, but it was possible to maintain tolerances prototyping my first training landmine that is inspired by the Russian POMZ-2.
The entire assembly is made of aluminium alloys. There are several interlocking parts, that had to fit tightly with each other. Different O-rings that needed to be squeezed and stretched accurately to perform.
There are only two commercially available valves in the apparatus. The third valve and ALL the other components are made entirely on the S3, including all the steps of manufacturing except for rigid tapping and painting of course.
So far I tested it with 9 bar (130 psi) and found no leaks at all.
Big thanks for the Carbide Team!