I have a TronXY RepRap 3D Printer. Not knowing much about it when I built it, one of the largest challenges I faced was getting the perfect distance between the extruder (print head) and the printing bed. The printer uses a sensor to determine accurate height, so you actually have to get both the sensor and the head measured properly. I use this simple procedure to line all of this up and all you need is a digital metric caliper and some business cards.
My business cards are 0.355mm thick and I need 9 of them for this.
For me I used one business card for extruder nozzle height and 8 business cards for sensor height. Yours may be different. You will need to experiment to see what is correct for you.
- Using software, move your extruder over your print bed so it is a few mm from the surface.
- Disable your stepper motors in case you need to manually make any adjustments by rotating the Z axis stepper motors.
- Measure both sides of the Z axis to make sure it is perfectly level. If it is not level, manually twist the stepper motors to ensure both sides match (no matter what the height).
- Loosen the screws on the Z axis sensor so it is not damaged as you lower the extruder.
- Place a single business card under your extruder nozzle.
- Lower your extruder nozzle so it is touching the business card, but not crushing it. There needs to be some friction when you pull/push your business card from under the extruder nozzle, but it should NOT be real tight.
- I used 8 business cards under my sensor. Yours may vary. Manually adjust the sensor so it’s bottom lies flat on top of the business cards and tighten the screws. For me, 8 business cards is 2.875mm. Adjust yours as necessary based on your sensor. Your specific details may be labeled on the sensor.
- Auto home your extruder and perform a bed leveling test.
- This is key! Start a print of something fairly large and watch the extruder nozzle output. If the nozzle is dragging the filament around corners, your nozzle is too high. Re-tune with 1 less business card under your sensor. If the output is almost invisible -smeared onto the print bed, your nozzle is too close. You could ADD a business card to the stack under the sensor and re-test. What you want is a print where the output is sticking to the surface without moving when the nozzle rounds corners. My headed bed is around 55C, and I print PLA at 200 degrees.
There are probably better / more accurate ways to do this, but This method works well for me and I hope it helps you get through this learning curve faster that it took me. As with anything, practice makes perfect so start printing and adjust as needed. Enjoy!