If you do a lot of work with 3D printers, then YouTuber Elite Worm has put together a DIY gadget that could be a big timesaver: a clog detector. Built on a small PCB and with connectivity to either a Raspberry Pi or the printer’s board, the small device alerts you when and if the printer’s nozzle becomes clogged, enabling you to pause or cancel the job. While clogging isn’t necessarily common, being alerted immediately should a jam occur during a large job allows you to get everything back on track right away.
The video below shows a step-by-step of a detector being made and tested, with a bill of materials available in its description. The base parts include a Digispark ATtiny85, an OLED display, a tactile push button, and a buzzer, as well as parts like resistors, ball bearing, screws, and wire. You can set up the tinyAVR MCU and test the program before any soldering is done, then put it all together and in a case if you wish. The finished board rests on the top of the extruder, attaching with some double-sided tape. It connects to the 12V DC rail of the hot-end fan and activates as soon as it is turned on. The sensor detects the nozzle's output; if no pulse is detected within a certain threshold, it will start beeping.
The code and necessary libraries and files, as well as files for printing a case for the device, are all available via the YouTube description too. The fairly quick project could just make life a little easier for those who bring a lot of projects to life with a 3D printer.