Customizable Helical Pen Holder Generator
A fully parametric helical pen holder generator.
Parameters include: pen number, model radius, pen angle, bevel, etc. I also highly suggest that you use the test function in order to fine tune your model before printing. Essentially, you can use the Customizer app to create a pen/ pencil holder that matches perfectly with your collection.
Feel free to suggest any improvements and point out any bugs you find. I'll gladly make any necessary changes.
A collection of parametric things: http://www.thingiverse.com/HotIceT/collections/parametric