Update: 1/5/2017
New module has thicker walls and rails. The modules interlock nicely and do not pull apart. The drawer fit test is a quick test to ensure the drawer will fit inside before printing the full module. I recommend scaling the module to 102% and leaving the drawers at 100%.
This is an extension of my Modular Hex Drawers. The problem I had with my original design was that it needed a stacking piece. I designed these modules to be fully stack-able.
you can find my Modular Hex Drawers here:
http://www.thingiverse.com/thing:1612401