If you don’t care about precise size, balls can be made cheaply by dropping drops of metal down tower where they are cooled by air as they fall, and then by water after they solidify. Then just sort by size

they do that anyway, there’s a lot of ground. balls have lowest drag per mass for randomly oriented tumbling object

you can just pour balls in but any other shape has to be arranged one by one

the waste heat comes from cryogenics system that keeps all of this helium at below 3K. turns out you need to spend a lot of energy to cool down things to temperatures this low

if you try to damage glass chemically i suggest you to find something better to do

this video is old, like from first year or so