OR: 1) Create a box of WALL(normal wall) 2) Create 4 blocks of FAN of equal size(not necessarily equal shape) 3) Put the fan directions facing 90 clockwise from the previous one(there are tutorials if you don't know how to do this) 4) Place whatever powders you want in the box(broken metals, stone, sand, concrete). 5) Melt down the powders. 6) Wait. 30-60 seconds should do it. 7) Pause 8) Cool down the particles until they are below their melting point(below 800 C is usually good) 9) Delete the FANs using the delete wall tool. 10) Save as stamp, use as many times as you like.