Optocoupler PCB For Laser Etching For ABL

thingiverse

My new capacitive ABL kits are now available on eBay at https://www.ebay.com/itm/233183828678 with a competitive price of $39.99, featuring pre-configured firmware for Ender 3/3 Pro, CR-10 Series, and other non-Creality printers using a 2-wire normally closed Z endstop. Setup is incredibly easy: simply mount the probe (OEM Bracket), plug in power and the Z end stop connector, upload the ready-to-flash firmware, and calibrate! The kits come with Vanilla Marlin firmware that includes support for SD cards and thermal runaway protection. UPDATE 2/11/2019: I've added a "calibration coin" .stl file to help position the sensor offset when mounting. Detailed setup documentation will be available soon. I've also included my CR-10S Marlin source with various features enabled, such as original Creality boot and status screens, PID control, auto-temp, bilinear ABL, 4-corner ABL, babystepping, LCD-adjustable preheat, EEPROM store/load/failsafe, and LCD-adjustable software endstops. UPDATE 2/5/2019: I've added gerber files (eagle.zip) for Excellion machines, which should be supported by many board houses. I use OSH Park for my PCBs. I've edited the .bmp file to get the focus just right for laser etching and experimenting. The .jpg can be used for photo-resist etching or toner transfer methods. Watch this YouTube video to see the capacitive sensor in action: https://www.youtube.com/watch?v=8vNrOkRvHPQ UPDATE 2/4/2019: I'm about to try laser etching the first board using Laser Etch software (link below). I've tested the capacitive sensor and it works perfectly. Future mods include a jumper for 12V/24V operation to prevent damaging the optocoupler's internal diode, and possibly adding a DC barrel jack. IMPORTANT: For 24V power, replace resistors with 1k ohm value. Also, check your Z endstop with a volt meter. The CR-10S was reversed from the Ender 3, so on the Ender and CR-10 series printers, the Z endstop is active HIGH. The optocoupler PCB design is for use with capacitive proximity sensors. I've tested it on a CR-10S with auto leveling enabled, and it triggers the Z end stop perfectly. It runs on 9 to 12 volts from your PSU or external power source. More on this project as it progresses, but the PCB does work. I've tested it on a Creality Ender 3 Pro and CR-10S with a 2-wire Zmin cable. PCB Dimensions: 33.96mm x 20.31mm (available in .dxf file format) Here's the etching software I use for PCBs: Laser Etch (https://jtechphotonics.com/?product=laser-etch-bw-image-engraving-sw-license). Simply open the image, adjust your settings, and the PCB image will be the correct size. Sensor: NPN Type / Normally Open (available on Amazon at https://www.amazon.com/gp/product/B0746FYF5S/ref=ppx_yo_dt_b_asin_title_o00__o00_s00?ie=UTF8&psc=1) BOM: * 1 x screw terminal or Molex connector for power input * 2 x molex JST connector for sensor and endstop * 2 x 470 ohm resistors (use 1k ohm for 24V operation) * 1 x LED * 1 x general purpose reverse protection diode * 1 x PC817 or EL817 optocoupler