FrankenHolder - pen/tool holder

Use zero top layers to expose the fill and hex infill to customise the hole size. 10% fill makes 18mm holes, I found 15% giving 12mm a good size.

The pair are at 100% scale and the larger one at 150%

Derived from [cerberus333](http://www.thingiverse.com/cerberus333/overview)'s [Frankenstein's monster bust](http://www.thingiverse.com/thing:23385)

The red one in the photo is [mizliz](http://www.thingiverse.com/mizliz/overview)'s [Frankenstein Walker](http://www.thingiverse.com/thing:2546