The inspiration: Do something that makes you happy.

The Objective: Sometimes, we can lose sight of the fact that we are developing skills with the potential to bestow happiness upon ourselves and others. Don’t forget that engineering can make incredible things. Go make an incredible thing.

The Tools: whatever you need

The Focus: Quality, purpose, pleasure

The Process:

Finding a source of inspiration wasn’t difficult; a favorite toy of mine had been breaking consistently, a beautiful hand-carved slingshot from Indonesia. I wanted to find a way to replace my toy with something that could withstand my somewhat rambunctious lifestyle.

After some research into slingshot designAllen_Elle_ps10_201_process

A model was whipped up in Solidworks with a few extra features: holes for adding later carved wood inlay, and a hole for machine fixturing and adding a tie to

Initially, the thought was to ensure this was feasible to manufacture simply, so a wooden prototype (shown later) was made in roughly an hour before going into design for metal

After a brief and foolish foray of thinking hand tools were a time-efficient way to make a metal slingshot,

the decision to move to CNC milling was made. Relying on prior experience in MasterCam X7, a toolpath was quickly created and can be viewed here

The program would take about an hour and a half to run on a HAAS CNC mill, so all of the various tools were set and the program started


Some polishing and deburring later,

Shoots like a dream!


Because the emphasis of this class has been on excellent design and presentation, and the emphasis project was to make oneself happy, what made me the happiest was to create a flyer made to present the antithesis of good design–early ’90s bad internet style. A presentation video of the manufacturing design that went into this can be viewed here