Vòng đệm (spacer) cổ phuộc xe đạp threadless dạng tham số (parametric)

Update 9 Jan 2020: Thanks to zachariazh for pointing out that you can pay nearly 20€ for what is basically the same exact thing from Extralite, the Italian manufacturer of super lightweight weight weenie parts. The only thing you don't get with my design is the "Extralite" logo printed on the side. Considering their scale photos compared to mine, I thought about putting an "Extraliter" logo on mine but that might be a bit much.

Plenty of headset spacers available online, probably because a headset spacer is basically a simple hollow cylinder. Not the most complicated design.

What makes mine different? Not a whole bunch, but I do have several varieties available along with the basic simple spacer:

• Hourglass spacer
  Thicker at the ends, thinner in the middle. Results in the lightest spacer which is perfect for the weight weenies amongst us.
• Rounded hourglass spacer
  As above, narrower in the center, but takes a nice smooth curve from top to bottom.
• Internally butted spacer
  Similar to the hourglass spacer, but the butting happens on the inside. Looks more conventional from the outside but is still ridiculously light
• S-Works clone spacer
  A clone of the carbon fiber spacers that came on my Epic that has a simple splined design.

Simple straight spacer
Because why not?
The design is parametric, if you import the F3D file into Fusion 360, you can go under Modify and choose "Change Parameters" and update any of the user parameters to regenerate all the spacers. The best approach here is to know how many spacers you need and print one spacer of the appropriate height, vs stacking spacers to get that height.

Two other cool designs:

T70E's cool "wave" headset spacers: https://www.thingiverse.com/thing:2514543

• FooFighter's adjustable headset spacers: https://www.thingiverse.com/thing:1640992

Printing

Can print in any material, but I'd advise against PLA because of the low heat tolerance. PETG is a softer plastic so might not be perfect, especially if you're going with the weight weenie versions. ASA is a version of ABS with UV resistance so would be good for bike use, but can be tricky (and stinky) to print with. Polycarbonate is also an excellent material for this. Any carbon fiber filled filament should also be quite good.

Layer height is pretty much whatever you want, I do suggest using the Arachne perimeter generator if your slicer supports it. (the big ones do)