Delta Printer: Slighty incorrect print alignment on the build plate After building a Delta printer, I noticed that my whole prints are slightly tilted around the Z-axis in comparison to the slicer (e.g. Cura). There is no twist layer wise. This means, the prints themself look actually perfect. 

I just don't know what could be the reason of the rotation. I do not believe it is a build issue of the printer, because I tried to keep the printer frame pretty stiff and symmetric. 
Could it be, that the Auto-Calibrate Feature of Marlin can add such a rotation?

The picture below illustrates the problem. I expect the black alignment of the print and get the orange one. Note that the print is still a rectangle with ~90° corners.
I figured out that the reason is probably a slightly translated slider construction. Instead of using a proper centered slider as shown in red, I used a slider construction like illustrated in yellow. When all sliders are translated on each tower like this, the print should be tilted by the same amount. This seems to have no influence on the general shape of the object. However, for my next printer I will use a proper centered uni-body slider.