There is somebody here experimenting with thicker alu supposedly doing 1kg reactions, but patton is right, foil works best.You are welcome to try but you will beat your head against the wall.I personally tried discs, pellets, sheet NOTHING worked better than 0.25 thickness aluminium obtained from weighting discs, it's almost foil but not quite.
Also I refuse to believe you don't have plastic barrels and piping. Jacketed reactor with a barrel within a larger barrel, condenser a big pipe inside a small one, smaller tubes fitted for water flow boom you have a really good reactor setup.