Compliant Bicycle Stem Mounted Phone Holder

thingiverse

Here is a phone holder I made for my road bike. It's designed to hold a Samsung Galaxy S9 in an Otterbox Defender case to a road bike's stem securely. The snap-in system features live hinges, making it easy to use and surprisingly strong. Using PLA, I can quickly click my phone into place, then pick up my bike off the ground while holding only my phone. The print is relatively fast at around 2 hours for both pieces. Be sure to use layer heights no larger than 0.2mm or the hinges will not print properly! Mine came out great at 0.2mm. Arrange the pieces as shown in the picture, making sure the holes for the captive nuts in the stem clamp are facing upwards. I'm including a .step version you can modify to fit your setup. My bike has a 32mm stem tube with a 5° downward tilt. The phone case measures 80.5mm wide and has a 60° tapered bottom edge. If your phone is smaller, I recommend filling the inside of the clamp and removing the appropriate profile to suit your phone's dimensions. It's also essential to use only cases with a silicone or polyurethane outer case, as slippery cases may slide out. You may consider printing in TPU, but you might need to shorten or thicken the hinge members. If you'd like me to modify a version for your phone and bike, send me a message with your specs. This design was created in Fusion 360 and inspired by the compliant mechanisms developed at BYU_CMR. As such, it may be protected by a patent and not available for commercial use. Hardware required: * 3mm x 16mm socket cap machine screws * 3mm hex nuts * 5mm countersunk screw from the bike's headset cap Instructions: Print both pieces. Remove your head tube cap and hold onto it in case you need to adjust your stem in the future. It's only needed to preload the headset bearings while making adjustments to the stem. Install the head tube clamp using the original countersunk screw, tightening just enough to hold the clamp in place. Alternatively, you can skip the head tube clamp and print 2 stem clamps if your stem has a different tilt. Insert nuts into the upper part of the stem clamp using a 2mm hex key to center and align. Install the stem clamp to the stem using 2 3mm screws. Position the clamp to hold the phone near the top without coming into contact with your volume or power buttons, then tighten. Install your phone by sliding one side into the clamps, press down, and squeeze the clamps to the center to click the other side into place (see video).