Suicide Switch

thingiverse

Disclaimer: I am not responsible for anything you do. The Problem: Many times, I've found myself needing to run a print well into the night, leaving me with two unappealing options. Leave the printer running all through the night or wake up at some inhumane hour to turn it off. The Solution: I discovered a reliable and simple solution: enable your printer to pull the plug on itself at the end of the print. This ingenious idea has saved me from countless sleepless nights. My Printer's Evolution: My printer started its life as a Da Vinci 1.0, but it now runs an mks gen 1.4 board with servo outputs. Your printer may have different specifications, so be sure to adapt accordingly. What You'll Need: To implement this solution, you will require the following components: A control board equipped with a servo output. 1 x R/C Relay such as https://littlebirdelectronics.com.au/products/pololu-rc-switch-with-relay-assembled 1 x r/c servo extension cable 1 x regular relay such as https://littlebirdelectronics.com.au/products/30a-horn-relay-spst 1 x momentary push button of your choice (hereinafter referred to as the ignition button) Refer to the diagram for wiring instructions. If it doesn't make sense, perhaps you shouldn't be tampering with your printer. How It Should Work: Power switch off: Press the ignition button – it will power on but then die when you release the ignition button, which isn't what we want. Power switch on: Press the ignition button – it will power on, energize the main relay, and remain on even after releasing the ignition button. This is our desired outcome. To shut down your printer: 1. Power switch off – no explanation needed. 2. Insert 'm280 p1 s2000' in your end g-code (where 'p' represents the number of your servo minus one). I used 'p1' because my Z-probe was set to 'p0.' This command will activate the R/C servo, which interrupts the circuit keeping the main relay closed and, consequently, power supply on. It's like a game of dominoes. Possible Issue: The mks gen 1.4 board retains consciousness if connected via USB even when the main power is off. To prevent this, it's wise to call 'm280 p1 s0' after the kill command to ensure the R/C servo and relay release their grip. In some cases, my 'm280 p1 s2000' command is ignored. I found that calling 'm280 p1 s0' beforehand resolves this issue. To be safe, add these commands to your end g-code: 'm280 p1 s0' – R/C relay closed (default option) 'm280 p1 s2000' – R/C relay open, kill everything 'm300' – beep to give you some extra time and ensure the printer is fully dead. 'm280 p1 s0' – reset R/C relay in case USB power is present. In this scenario, your printer will remain off until you press the ignition button. Firmware Adjustments: You might need to make a few simple adjustments to your firmware (I use Marlin) if you haven't already enabled servo functionality. A Note from My Experience: The screw posts for my R/C relay servo broke when I tried to install it. Instead, I used double-sided tape as a makeshift solution. The big servo requires an M3 screw, while the RC servo uses 2mm self-tapping screws that I had lying around.