I'm attempting to build first phase change cpu cooling system, and i've got everything i need on order. That is, except gass. From what i can tell r290 & ln2 (for testing & brazing) are unregulated, but I cant for the life of me find a supplyer which doesnt require you do a safty course first.

Now I can see the logic in that, but if i want to blow myself up, thats upto me, its allready costing me a small fortune. does anyone know a uk supplyer where i can buy such gasses?

otherwise I guess i'll do the course.