The headset on my Tour Easy ‘bent worked its way loose, which led to a disturbing discovery: the headset wrench I made from a discarded flat wrench vanished with the shop tools donated to MakerSmiths.
Fortunately, we live in the future:
A thin plastic wrench is absolutely no good for torquing down the locknut, but that’s not what it’s for. Adjust the bearing race to the proper preload with this wrench, hold it in place, then torque the locknut with the BFW.
The OpenSCAD source code as a GitHub Gist:
Now, I’d like to say that was easy, but in actual point of fact …
First, I forgot to divide by cos(180/6) to convert the across-the-flats size to the diameter of OpenSCAD’s circumscribed hexagon-as-circle, which made the wrench uselessly small:
If you have a 28 mm nut with low torque requirements, though, I’ve got your back.
While I had the hood up, I slenderized the handle into a much shapelier figure:
Trotting off to the garage with a warm plastic wrench in hand, I discovered the blindingly obvious fact that the headset nuts have eight sides. On the upside, the number of sides became a parameter, so, should you happen to need a five-sided wrench (perhaps on Mars), you can have one.
So, yeah, it’s rapid prototyping in full effect:
Remember, kids, never design while distracted …