This is an adapter for a Light & Motion Taz bicycle light, to fit a GoPro mount.
Here's the Taz light: http://www.lightandmotion.com/choose-your-light/taz
Print with 100% infill, and 2 shells to make it pretty much solid, to maximize strength.
It requires a M3-.50x12 (metric) bolt. Obtain a M3-.50x12, 2mm hex bolt. This longer bolt provides more mating threads with the light, and also allows for a thicker part at the mounting hole, making it stronger overall.
I preferred the 2mm hex bolt head, because bicycle tools typically have a 2mm allen key. You may prefer a philips, flathead, or other variant.
The Taz light is mounted upside down, with this longer mounting screw. I found that the original Taz mounting screw was too short to give me confidence that it's bolting surface area and clamp-able thickness of PLA would hold up over bumps and jolts the bike experienced on the road.
Note: originally I didn't print with 100% infill, and the adapter broke over the first big bump my bike hit. I've ridden dozens of miles with the 100% infill part, over very poor pavement, and it's held the light just fine.
Use 2 shells and 100% infill. Print with the GoPro mount's legs facing up. Supports shouldn't be needed, but it depends on your slicer.
Clean off any raft or supports with a knife. Use a flat file or sandpaper to insure the mating surface for the light is flat and free of support material. Use a hand-drill to even out the two holes with appropriately sized drill bits.
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