WindowSense runs on a Raspberry Pi Zero WH with a Sense HAT, and both are mounted inside a custom 3D-printed case. With a minimalist design and printed with Protopasta's Matte Fiber White HTPLA, the case has an earthy texture that blends in with analog surroundings and decor.
The WindowSense case was designed parametrically in Fusion 360. The mounting hole dimensions of the Pi Zero and Sense HAT were used as fixed construction guidelines around which the case is deployed around the electronics as snugly as practicable.
The two halves of the case snap together with a friction fit as a satisfying click. A small window in the shape of the WindowSense "logo" allows a peek at the PCBs inside and the ability to see the Raspberry Pi's power LED. A decorative joystick cover can be attached to the Sense HAT's five-way joystick button so that it can be operated through the case.
The internal standoffs have been designed to hold the combined Zero + HAT just right and allow mounting with just four screws and two spacers. The USB power cable is routed internally to redirect it for a straight exit out the bottom of the case, which allows for the flat cable to be oriented downward, for wall mounting, or backward, for tabletop use. An additional slot at the bottom edge makes it easy to pop open the case by inserting a flathead screwdriver and giving a gentle twist.
Raspberry Pi Zero WH
Raspberry Pi Sense HAT
USB-to-Micro cable
Clear acrylic panel
White vinyl decal
M2.5 screws, 15 mm x 2
M2.5 screws, 5 mm x 2
Nylon spacers 11 mm x 2
The STL File on Thingiverse contains all three parts of the case: the back plate, the front cover, and the joystick handle. It is already laid out for printing on even small printers, and the models require no special techniques, settings, or printer hardware to create.
I printed my case in Protopasta Matte Fiber HTPLA - White to give the case a natural appearance that doesn't look like plastic. The design should print well in any PLA filament, however.
- Attach the Sense Hat to the Pi Zero header.
- Place the combined Pi+HAT onto the standoff pegs of the case's back plate.
- Insert the nylon standoffs between the two PCBs of the Pi and the HAT where they are attached, and then the long screws through all three into the back plate.
- Insert the short screws through the other two holes of the HAT.
- Plug in the USB cable and wrap it up around the standoff toward the top of the case and then back down so it can exit the case straight out the bottom.
- Using a sharp blade, score and then carefully break the 0.050in acrylic panel into a rectangle that is sized to fit snugly inside the small ridge on the inside of the front cover so that it will be held in the appropriate location to cover the LED matrix.
- With the piece of acrylic panel you cut, cut a slightly larger rectangle of the vinyl film.
- Prepare the plastic panel with a solution of soapy water so that you can reposition and smooth the vinyl when you apply it (it will dry invisibly)
- Remove the vinyl's backing and apply it carefully to the plastic and then gently smooth out any bubbles using your finger or something with an edge that won't scratch the vinyl, such as a credit card.
- Once you are happy with the application of the vinyl, trim off any excess around the edges.
- Place the complete screen, vinyl side in toward the LEDs, into the raised outline which will help keep it in place. You may want to secure the panel to the front cover with a tiny dot of glue at the corners.
- Snap the back plate and front cover together--they are a friction fit.
- Place the joystick handle on the tiny joystick nub through the hole on the front of the case.
- Find a visible place to put the WindowSense on a wall or flat surface.
- Plug it in and get it running!
