Judges/Everyone - please view the Making-Of video at https://vimeo.com/181556448 (dozens of hours went into video production).  Features:

• Design Methodology
• Engineering Challenges
• Assembly Demonstration
• Excellent Handwriting!

Spin Sling 360 Knob to Lever Kit was designed to turn door knobs into levers.  

Functional Design Features

• Concave Lever for Easy Fist Handling
• Free Spinning Lever for Easy Pulling
• Universal Design for All Knob Diameters

3D Printing Features

• 100% 3D Printed - no hardware (nuts, bolts, etc.)
• No Post-Processing - all parts print without supports
• Basic Materials (PLA or ABS) - no exotic filament required (like flexible filament)
• All Mechanical Connections - no adhesives/glue 

A New 'Spin' On Door Levers

Fundamentally, door levers are made to grasp with fingers.  There is not enough clearance between the door and the lever for a fist when pulling.  The Spin Sling 360 has a concave lever that spins.  Simply turn your wrist to spin the lever and the concave shape adds extra clearance for your fist.  Brilliant.

Print Settings

All parts were printed as follows:

• Nozzle: 0.4mm
• Layer Height: 0.1mm
• Speed: 50mm/s
• Supports: None
• Adhesion: Skirt
• Infill Density: 20%
• Slicer: Cura