Increasing the accuracy of your Auto Level

As usual, as summer arrived and my basement has 20F swings the head offset constantly has to be trimmed.

The head offset is referenced all the way through housing plastic to a end switch in the bottom of the R2. The expansion of the case due to temperature causes this error.

When setting up the software in the IR board for Partsbuilt, I wound up using two different offset mechanisms. G36 and G29. During the winter both worked identically. I began to have my summer problems and discovered that the machines with G36 did not suffer the same offset problems.

G36 makes one additional offset measurement at the beginning of the of the auto level. I can not verify it in the code but I think it resets the offset and eliminates the problem.

I have attached both of my GCODE scripts G36 and G29.

The way I set them up is to: start a print, the GCODE script then heats the bed (print head remains cold to avoid drips) and performs a G36(29). The head then proceeds to the rear left and heats the print head to 200C When the print head reaches 200C the bed raises to print position I can then check the gap with no hard plastic blob on the end of the print head pressing into the bed. It now raises print head to 220C. If not enough gap I turn off printer, turn back on and readjust. If gap is too much I allow print to start printing then cancel and readjust the gap. Continue until satisfied.