I modeled this openbuilds corner angle to  print and mount 2020 Aluminium Extrusion on a 3d Printer.

It is not intended for heavy things, just small an light things.

Rounded the corners of to get it to print nicely.

Print it as imported into your slicer

Prusa Mini

Esun ABS+

4 Outlines 

40% Infill

5 Top and Bottom Layers