MUJI Drybox - with LED humidity indicator

prusaprinters

<p>Based on A4 storage box from 無印良品.<br><a href="https://www.muji.com/jp/ja/store/cmdty/detail/4550002555702">https://www.muji.com/jp/ja/store/cmdty/detail/4550002555702</a></p><p>Each box contains a digital pressure/temperature/moisture meter (BME280), an RGB LED (PL9823), and a DB9 connector for a straight-rs232 cable.<br>Sensor can be bought on Amazon.<br>LEDs in Akidzuki Denshi (in akihabara).<br>Cheap DB9 cables and connectors in Marutsu (also akihabara).</p><p>Connection box, mounted at the back of the printer, allows connecting up to 8 boxes to a Raspberry PI (e.g. the octopi driving your printer).</p><p>I used cables instead of wireless connection to avoid having to replace batteries every few months.</p><p>The boxes are <strong>not</strong> easy to open and close. You'll likely have to seal them with transparent tape, too. And the top covers are likely to fracture during closing. Basically, those top covers suck. I can't really recommend using them. If you have any other idea how to seal those boxes - go for it, and share.&nbsp;</p><p>Software for driving the LEDs from raspi is available here:</p><p><a href="https://gitlab.com/yunta/pl9823">https://gitlab.com/yunta/pl9823</a> - LEDs control tool</p><p><a href="https://gitlab.com/yunta/dry-box-example">https://gitlab.com/yunta/dry-box-example </a>- example script to color leds based on humidity</p><p>&nbsp;</p><h3>Print instructions</h3><p>I did not upload any gcode for the top covers, because every box is slightly different. Measure walls' thickness with a caliper, or something, and update the openscad files <strong>separately for every box you bought</strong>. Then slice as you like it. Supports are only needed for the "base" and "plug-box" parts (or maybe not, I haven't tried printing them without supports). Infill is irrelevant, I think.</p>