This is a box to house the components required to control a 4-wire fan used in my Air Scrubber project for my LACK enclosure.

The information is displayed on a 128x32 OLED display. https://ebay.us/rxHI4i

The control is performed by an Arduino Pro Mini (16MHz 5v). https://ebay.us/T4mzeE

The fan speed is selected by a 4 position rotary switch. https://ebay.us/NkEpef

Knob (23mm) for rotary switch. https://ebay.us/hsyoyO

The supply voltage for the fan is through a (5v) relay switched off by the Arduino. https://ebay.us/6b8B6j

Connector is 4 pin JST. https://ebay.us/Kgg9Wj

12vRocker Switch. https://ebay.us/8zmu28 I've used 90 degree spade connectors

12v to 5v buck converter. https://www.adafruit.com/product/4739 or https://tinyurl.com/5b9vddtf from Pimoroni UK.

Wiring for internal electronics 24awg. https://ebay.us/5w8QUT & https://ebay.us/QNX6Jp

The Gcode is in PETG with 0.2 layer height & 0.4 nozzle. No supports are required.

It's a fiddley assembly and I wish I had allowed more space and offset the power in and on/off switch.