Straight Nibholder with Triangle Grip

I got frustrated having to spend 15 minutes hunting for the right angle every time I picked up a straight holder. The triangular grip makes it easy to find the same angle again and again. I use it with a Folded Ruling Pen but it should fit many nibs with sufficient effort.

Designed completely from scratch in OpenSCAD. You know the drill, source files are on my site: http://burningsmell.org/3d/oblique-pen/