This is a case I made for use as a simple DIY fan filter for my 3d printer enclosure using carbon filters and with variable fan speed control.
Hardware needed:
-1x Dell Server Fan (Model PFC0612DE)
-1x DC12V Manual Four-Wire PWM Fan Speed Motor Controller Board
-1x SPST Toggle Switch
-1x DC Power Jack Socket
-1x 12V 2A DC Power Supply
-Carbon filters (~3/8” thick)
-Wire, solder, soldering iron, some screws, etc.