Whiteboard Tray and Cup, modular, parametric

This is a extension from [thing:1037034](https://www.thingiverse.com/thing:1037034) thanks to [hemocyanin](https://www.thingiverse.com/hemocyanin/about).

I added the Cup. Its customizable so you can figure out what to do with it. I personally use it to store my pens. But you can adjust the paramters that it fits your eraser or what ever you can think about.

This design is for 1,75mm filament.

Some original explanation:


>This tray will work with any whiteboard that has a frame made