UPDATE 2011-10-25 I uploaded shell-012948.stl, the file as exported from Sage, for shell thickening experimentation. It was mirrored from the original exported file because a hermit crab needs a right-handed shell spiral due to the way its abdomen curves.

Pimp out your hermit crab!

This is the prototype shell for Project Shellter, the current artist residency at MakerBot Industries.

It is modeled on the shell of the Cittarium pica sea snail, http://en.wikipedia.org/wiki/Cittarium_pica, and is similar to the ones that crabs in pet stores typically sport.

It was created using Sage, http://sagemath.org, exported to an STL using a modified version of Christopher Olah's plugin, http://trac.sagemath.org/sage_trac/ticket/7744, and thickened in 3DS Max.

You can explore other shell shapes here http://sagenb.org/home/pub/2928 (account required).

The goal is a workflow using open source tools, but the conversion of the surface to a solid at this point requires a commercial tool.

Maybe someone can figure out a way to thicken the surface without 3DS Max‽

Follow Project Shellter progress here:

http://projectshellter.com http://twitter.com/ProjectShellter http://bit.ly/ProjectShellter http://bit.ly/ProjectShellterCams http://bit.ly/ProjectShellterVideos

This was printed on a Thing-O-Matic with Mk 7 extruder at the world famous BotFarm using Matt's excellent support settings: http://www.makerbot.com/blog/2011/06/27/makerbot-microtip-using-the-support-features-in-skeinforges-raft-tool/

Some notes:

• It is oriented to eliminate interior support settings; re-orient at your own risk ;)
• You only need the STL or the zip file; they contain the same thing
• Once printed, the minimal support material is easily removed and the entire shell is hollow
• Sanding or tumbling to smooth the surfaces is optional but recommended (more on this later...)

You can print it, I know you can!

Go!

Thanks to @JonMonaghan for the 3DS Max-fu, print and photos (my first print failed, and he kindly reprinted it for me so I didn't miss my flight).