SR Suntour fork top cap socket (FAA122/FAA086 replacement)

thingiverse

I recently attended professional bike tech workshops through the Professional Bike Mechanics Association where I received training in a wide range of subjects from various brands. I was constantly thinking "I bet I can 3D print that" and this is the first of several posts inspired by these seminars. SR Suntour produces a broad array of forks, but most people are familiar with their heavy steel forks like the XCT found on many entry-level bikes, mountain bikes, hybrids, etc. Previously, I viewed these forks as low quality, but that's not fair or accurate. They're inexpensive and feature brilliant designs that make them completely serviceable. In particular, the bushings' design is exceptional; they can be removed with a screwdriver and quickly replaced. To perform this maintenance, you need the FAA122 tool, which you can see in the photos. Considering the FAA122 is plastic, I immediately saw the possibility of printing one, and turning it into a socket seemed like the obvious way to go. The torque spec on the socket is only 10 Nm, and with multiple points of engagement on the splines, this tool can handle that easily. It's likely I could even print it with a 3/8" socket drive without issues, but the 1/2" is stronger as it distributes the drive forces over a larger radius, thus reducing stress on the socket. Thanks to Jon Wells of Envelo for his assistance in this project. Thanks also to jaybeckr for modifying this to work as an FAA086 replacement; I've included his STL file. A Fusion 360 F3D file is also included if you want to make any changes.