Dual extruder calibration objects

Calibrate your dual extruder XY offsets with minimum effort and material waste.

Use only around 50mm of each material.

First eyeball the offsets so the extruders fall in around 1mm range when switching between them (use T0 and T1 command).

One method I found useful is to stick a piece of blu-tack in the middle of the bed, lower your extruder to make a mark on the blu-tack, then switch to the second extruder and make another mark. Then you can measure the XY distances of the 2 marks a