Longboard Footstop in OpenSCAD

My local library, the Hillsboro public library, has 3D printing open labs — every Monday evening for a couple of hours, the library accepts .stl files on thumb drives and prints them for free over the next week. This is such a cool resource, it seems irresponsible not to take advantage of it.

For my first project, I decided to design a longboard footstop.1 Earlier this week, I started researching 3D CAD software and settled on OpenSCAD.2 OpenSCAD is different from most 3D CAD software in that you program a part instead of manipulating objects on a screen. For example, this is how I defined the tab of the footstop:

union() {
tab_s = tab_length - tab_width/2;
tab_r = tab_width/2 - stop_chamfer;
tab_h = 2*(tab_height - stop_chamfer);
translate([-tab_s/2, 0, 0]) cube([tab_s, 2*tab_r, tab_h], center=true);
translate([-tab_s, 0, 0]) cylinder(r=tab_r, h=tab_h, center=true);

Designing the footstop, some of OpenSCAD’s other limitations became obvious: fillets and chamfers are not easily defined, especially along curved intersections of primitives.3

This is my third iteration of the footstop and I think it’s good enough to print next week so Jamison can try it out. I suspect I still have a lot to learn when it comes to getting a design ready to print. For example, how important is it that this footstop be hollow? If it needs to be hollow, what’s a reasonable wall thickness? I experimented with MeshMixer a bit, but expect I’ll need to wait until Monday.

I wonder what I should design next. I think I’d like to try some sort of GoPro mount.

  1. If imitation is indeed flattery, RipTide and PSD Designs should feel complimented. ;-) 
  2. Pronounced open ess cad
  3. I’m gathering resources that address this issue. 


Author: Brent Logan

Engineer. Lawyer. WordPress geek. Longboarder. Blood donor. Photographer. More about Brent.

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