Instructions

Now we will finally calibrate the distance between the tip of the nozzle and the probe.

You can launch the calibration from LCD Menu - Calibration - First layer cal.

The printer will probe the bed and start printing a zig-zag pattern on the print surface. The nozzle will be at the height based on the SuperPINDA probe setting, it must not by any means touch the printing surface. If you have already calibrated the first layer and you run the process again, the printer will ask you whether you want to use the old Live Z value. 

Observe the line which is being extruded on the print surface. A new menu will automatically show up where you can tune the nozzle height in real time by turning the knob. The aim is to adjust the nozzle height until the extruded plastic sticks nicely to the bed and you can see that it is being slightly squished. 

Posible Results for Final Sheet Print During First layer Calibration 

Too high

You want the line flattened, but not squished. On the square at the end of the test line, you do not want any gaps between the lines (left picture), which means it is too high. In that case, the value will be too close to zero

Too low

If the nozzle is set too low (right picture) you will see the line squished completely flat and the end square will have ridges between the lines, which is a clear sign it is set too low and the value will be too far away from zero. When it is too low, the edges of the square can also start curling upwards. In the extreme, the filament will be spread so thin you will be able to see through the printed filament, leading to clogging of your hotend.

Having the nozzle too low can cause the nozzle to damage your steel sheet. This is not covered by Warranty.

Just right

A correct adjustment will show you an even surface (center picture), with no gaps between lines, nor ridges. As stated, the numeric value depends on the exact position of the P.I.N.D.A./SuperPINDA sensor, which will be unique to each machine and means nothing without a visual reference. However, a common range is from -0.400 to -1.500.

The Z value should not exceed -2.000 mm. If you have to adjust it more (e.g. -2.500), move the SuperPINDA probe slightly higher. Please refer to help.prusa3d.com in case the SuperPINDA probe needs to be re-aligned.

Loosen the M3 screw on the probe holder to make adjustments. Gently push or pull the sensor to adjust the height and tighten the M3 screw again. Then re-run Calibrate Z followed by the First layer calibration again.