DETAILED first layer calibration for Revo Six (or any 0.25, 0.4, 0.6, 0.8mm) nozzles

If you simply want a fast way to set or confirm your Z heights, try my QUICK first layer calibration for Revo Six (or any 0.25, 0.4, 0.6, 0.8mm) nozzles. Use these DETAILED files if you are willing to take more time and really dial in your Z heights.

I recently upgraded my MK3S+ to the Revo Six hotend and have loved the ease of switching nozzles sizes. Unfortunately, the Prusa's onboard First Layer Calibration is only tuned for the stock 0.4mm nozzle. I couldn't find any first-layer models that followed Prusa's First Layer Calibration of other nozzles recommendations so I made my own, remixing concepts from GKMAKEIT and ArtyL. These files should work with any brand of nozzle.

Step-by-step guide to calibration (from ArtyL that I modified):

1. Change your Prusa to 7x7 mesh leveling, if available.
2. For PLA, a SMOOTH steel sheet is recommended. For PETG, a TEXTURED sheet is recommended.
3. Clean your build plate. I only use 99% isopropyl alcohol and a lint-free paper towel.
4. Tell your printer which nozzle size and steel sheet profile you are using.
5. Run the print Gcode and start with a Z-offset that is at least above the bed.
6. As the printer extrudes the skirt, get the Live-Z down so at least the material is sticking to the bed. While printing perimeter, just get a decent line.
7. Print ~1 inch with a single Z-offset setting, then adjust down or up accordingly. I start with 0.01mm adjustments and then hone in with 0.005mm tweaks.
8. Once the print is over, let it cool. Then use your fingernail to gently remove the patch.
9. Is the patch rough like sandpaper or wavy? Raise your Z height. Does it have pronounced ridges or does light shine through holes? Lower your Z. You want a mostly smooth surface with faint ridges and no holes. See the photo reference.
10. I suggest writing the nozzle size and Z height(s) with a Sharpie for reference.

Video guide from GKMAKEIT: https://rumble.com/vb9fxr-3d-printer-first-layer-calibration-process.html

Design methodology:

• 130x130 square that covers enough of the print bed for calibration accuracy
• PrusaSlicer's “Generic PETG” and “Generic PLA” filament profiles applied
• each STL follows Prusa's recommended layer height for the respective nozzle:
  • 0.25mm nozzle = 0.15mm height
  • 0.4 nozzle = 0.2mm
  • 0.6 nozzle = 0.3mm
  • 0.8 nozzle = 0.4mm
• Gcode starts printing from the front and works backwards
• the "fill angle" is set to 0 (zero)