When he’s not working at Rusty Taco in Plano, TX, Brooks Ruhman is a student at The University of Texas at Austin.
He’s also a maker with a wicked sense of the absurd, and as a demonstration of that playful nature, Ruhman built himself a neat project which uses the motion of a bicycle wheel to drive an off-the-shelf car tire compressor. The parts for the project were fabricated using 3D printing and laser cutting and a whole bunch of ingenuity.
According to Ruhman, you can find a whole passel of things to use the compressor for from storing the compressed air in a tank to inflating tires to powering a misting system to keep you cool to pumping up a handlebar-mounted water gun.
Ruhman did the design and fabrication work for his project at the University of Texas Maker Studio using a Makerbot 3D printer and a Full Spectrum Professional Laser Cutter.
He says the air compressor itself was purchased cheap online – about $15 for the version he used – and once the plastic shroud and the electric motor of the original are removed and saved, you’ll be left with a “bare minimum air compressor; just a mechanical piston driven by a nylon gear.”
Ruhman designed the parts for his mobile compressor in SolidWorks.
“The flywheel was constructed with a combination of laser cut and 3D printed parts. If you don’t have access to a laser cutter, you could definitely complete this with any other circular object such as the bottom of a bucket or a coffee tin lid,” Ruhman says. “Basically the flywheel has to be both of a reasonable diameter for the area that you’re working with behind the bike seat, and sturdy enough to undergo the damage of road wear. I used two laser cut circles – made from 1/4” acrylic – and connected them with 3D printed spacers. The flywheel was connected to the assembly with a 3D printed faceplate.”
Ruhman then used a 20×12 Full Spectrum Professional laser cutter to make the acrylic pieces he needed, and those were designed in a program called Inkscape.
The flywheel was an 8″ diameter circle cut from a 1/4″ clear acrylic sheet, and the mounting bracket is made from that material as well. The entire system is mounted to the seat post and extends out over the tire and it was assembled using standard, off the shelf hardware like small nuts and bolts.
Ruhman says his compressor is connected to a long hose which can reach anywhere on the bike and can be used to pump up a tank or power a handlebar mounted water gun.
What do you think of Brooks Ruhman’s mobile bicycle-powered air compressor? Will you make one for yourself? Let us know in the Mobile Bicycle-powered Air Compressor forum thread on 3DPB.com.
by TE EDWARDS | MAY 26, 2015