/diy/ - Do It Yourself

>>2595625
You design a model, it's represented with cartesian coordinates.
You slice it, it's turned into a huge series of movements in cartesian coordinate space, represented by a huge list of cartesian coordinates.
You print it, your printer takes those coordinates, and directly translates them into movements at the axis.
100mm along the x-axis in CAD is the same as 100mm along in the x-axis in a gcode file and it's the same 100mm that your firmware will ask of your x-axis motor which will move your x-axis 100mm.
It's a direct linear relationship from start to end, and it translates into the real world flawlessly.

CoreXY, all the same until it hits the printer.
Then, it takes those cartesian coordinates, and uses an algorithm to translate them into the rotated CoreXY coordinate space in order to command the motors.
There is no direct relationship between a given coordinate in the real world and that same coordinate represented in CoreXY.

It will always be less precise, there will always be loss, rounding errors.
Picrel, those formulas, that's why CoreXY printers can't compete when it comes to precision.
In the real world, the differences are tiny, you lose more precision to G2/G3 arcs than to CoreXY kinematics.