Carbon Fiber Wheel Hubs

Our rover's old wheel hubs were these really gross, bulky, overdesigned 3D-printed PLA cones we'd been using since the dawn of our club. It was my job to redesign the hubs to hopefully save some weight while staying as strong as possible (our wheels remain the main shock absorbency system on our rover). 

I started by importing our wheels' geometry into Onshape, where I then tailored the hub profile around the wheel's internal curvature and made sure it was offset correctly to fit with our current gearbox/motor extrusion (see how they aren't symmetric in the cross-section view).  For the mold, I wood-lathed the  profile using a reference I laser-cut out of acrylic, sealed it with epoxy, and performed a 3-ply vacuum bag wet layup (my first time working with any kind of wet resin, or composites at all for that matter). After cure, I post-processed the parts on a Tormach PCNC 440 to release the hub from the excess fiber and get our screw hole profiles.

The finished hubs came in 50% lighter than the PLA originals, and was strong enough for me to stand on (as a 200lb man). More significantly, the project opened the door for composites manufacturing across the rest of our club; we ended up reaching out to Rockwell Composites and CompositesOne for mentorship on a carbon fiber rover chassis redesign, something that would have never happened were it not for this first experiment with carbon fiber on our hubs.

Skills