Fire Safety

I'm working towards getting my printer set up for longer, unattended prints, so I can make larger models.

My new hot end came with a thermal fuse built in, to make thermal run-away impossible. I have since added thermal fuses to the heat lamp and to the heated bed and power supply.

I also installed some passive fire extinguishers (in addition to the traditional fire extinguisher I keep near the door)

Next step will be adding a relay board to the raspberry pi that controls the printer, so I can remotely control power to all the heated elements and the entire printer.

Ventilation

ABS is not very pleasant smelling when you heat it up and print with it. It's also not particularly healthy to stay in a non-ventilated room with an ABS printer for long periods of time (although apparently it's not any worse than staying in a room with a burning candle). Here's an interesting summary of the latest science.

I've been leaving the window open while the printer is running, but that's not a great long-term solution. My long-term solution (what I intended since I got the printer) is to use our radon mitigation system (basically a powerful fan vacuuming air from our sump system and exhausting it outside) for active ventilation. Conveniently, the radon mitigation assembly is in my shop, a few feet from the Rostock:

This afternoon I removed the plexiglass, and installed a cleanout with a screw-in cap:

Now, while I'm printing, I'll leave the cap unscrewed, and plug it back up when the printer is not running. No more worries about leaving a ground-access window open overnight, and now the ventilation is active instead of passive. The manometer on the radon mitigation system didn't even noticeably change when the cap is open compared to when it's closed.