Quantity   Component name
2 × 32x43cm plywood top and bottom
2 × 32x88cm plywood sides
2 × switches see schematic
2 × hinges for the door, of course
2 × 43x90cm plywood back and door
18 × 1.5x31cm plywood rack and distributor holders
6 × 2x2x31cm pieces of wood structural braces
1 × 31x40cm pegboard air distributor
4 × chunks of wood for legs How high do you want it off the floor?
8 × food safe wire racks cheap BBQ grills work
1 × heater (a few hundred watts depending on your design)
1 × fan If you use a PC fan, you'll need a way to power it as well