PLTW Automata Holder

The new Introduction to Engineering Design curriculum for PLTW includes an automata project. Students design and test cams and then build an automata. PLTW sells kits for this project that make the construction very convenient. This holder was designed to ensure right angles and straight sides - it saves both time and materials (like glue).
I've been having trouble with the corners peeling up from the print surface for any large prints on my Makerbot Replicator +. After several iterations, I've found that using birms works better than rafts and no support material is required. The units used in design and in print settings are inches.

UPDATE: Have adjusted dimensions to better fit current PLTW automata kit dimensions.