SO3: How do you calibrate X&Y axis to make perfect circles/squares?

[WillAdams (William Adams (Carbide 3D))]

You have to start by calibrating for runout, and take the endmill cutting diameter into account first:

• http://docs.carbide3d.com/article/47-measuring-runout

Then calibrate for belt stretch:

• http://docs.carbide3d.com/article/42-how-to-calibrate-the-machine-for-belt-stretch

The do some cut testing:

• http://www.shapeoko.com/wiki/index.php/Calibration_and_Squaring_the_Machine#Diamond_Circle_Square_Test