Parametric Pen Tray

I wanted a tray, but couldn't find one with a cutout so you could actually get to the pens in it, so I made one.This tray prints standing up with no raft or supports, which brings the added benefit that the grooves the pens lay in aren't pixelated/layer-stepped.The FreeCAD file has a VarSet with a parameter ‘NumberOfPens’, if you want a tray for 3, 5, 42 pens.