Spool Dry Box Outlet With Filament Alarm

thingiverse

Here's a DIY dry box for filament with an alarm that sounds when the filament is out. I used an LED light, which lights up when the alarm goes off. You can connect the switch to your print controller or a piezo buzzer instead. I used a cheap storage box in the pictures and mounted two supports on either side of it. A threaded rod runs through all the spools inside. This setup is useful when you constantly change material type or color. The PTFE tube should hold its own shape, but a tiny drop of glue might be needed depending on how it prints. The battery holder can be stuck in place using a sticky foam pad. When drilling the box, use masking tape to mark the spots and add scrap wood as support to avoid cracking the box. For the electronics, I used a CR2032 battery connected to an LED light and the normally open contacts on the switch. You could also replace the LED with a piezo buzzer instead. A more complex setup would involve connecting the filament alarms to software via a microcontroller and maybe a wireless module. Let me know if you have any questions or comments about this design!