I recently bought a GPS-receiver, Garmin eTrex Legend HCx, mostly for bicycle trips and for improving OpenStreetMap. However, from what I've heard, Garmin's own bike mounts are not only expensive but also weak. Therefore I decided to make my own.

Btw, I've been happy with my purchase; the free OSM maps were easy to install, it navigates well along bicycle routes and the screen is visible in daylight.

Design

I found a few ideas online, such as this sponge holder, but I wanted a bit more.. hm, presentable version. It's important to keep the device fast when going over bumps. Nevertheless, I still want to be able to detach it while riding, e.g. to input data or to take a closer look at the screen.

Because this model does not have a magnetic compass, I chose to attach it with a magnet from an old harddrive. The magnet, in turn, is attached to a bit of polycarbonate that I bent to shape with hot air gun. The polycarbonate flaps keep the device aligned in bumps, and the magnet keeps it in between the flaps. Detaching is easy by just grabbing it at top edge and taking advantage of the lever effect.

Outcome

I planned to fasten the holder to my bike handlebar with two pieces of brass rod and some nuts. Would have been really sturdy, but I apparently made an error in the measurements, causing the bent rods not to fit. I substituted some zip-ties, which work just as well. In between there is a piece of rubber to increase friction.

I've done a few short trips with this setup; it sure holds the unit well. Only once I've had it twist out of alignment after accidentally poking it with my arm, and even then the magnet still kept it attached.