MPCNC 525 universal pen mount

I needed a solid pen holder for MPCNC 525. This model holds pen tight and it should not move around while using with MPCNC (tested).

Thanks to [wbarber69](http://www.thingiverse.com/wbarber69/about) for his [blank holder](http://www.thingiverse.com/thing:1634262). I used part of it.

Feel free to download full or just half size (choose the right STL for you).

Created in OpenSCAD.