“Tripod” update

I spent a little more time last night polishing my take on the Slopes tripod. In the process, I noticed there’s still more work to do. I expect this prototype will not be my last. My concerns are:

  1. I haven’t accounted for tolerances. Maybe I’ll need to make the openings 0.5 mm larger.1 With OpenSCAD, this would be relatively easy to do increasing the size of three objects by 0.5 mm on two dimensions each. With 123D Design, and the diagonal cuts on this design, I’ll have to do 0.25 mm tweaks on fourteen surfaces.
  2. The Slopes tripod has at least one relief cutout adjacent the shutter release. I’m going to inspect and measure Jamison’s GoPro camera and to see whether this effort is necessary.

I think the Slopes tripod is a great idea. I’m planning on getting a ReplayXD Prime X camera, even though its image quality is a little lower than the GoPro’s because the Prime X is much lower profile. I think I’m going to try making a low-profile tripod for a cylindrical action camera.


  1. It’s time to get some calipers so I can accurately measure the printed article to compare with the design. Right now, even though I’ve printed two (and waiting for the third) footstops, I don’t know whether printed articles are oversized, undersized, or what. 

Low-profile “Tripod” for GoPro cameras

Designing stuff with OpenSCAD can be frustrating. Not having the native ability to create fillets on edges, the workaround I’ve discovered1 is tedious and slow:

  1. Create a primitive object that is smaller than the desired object by the radius of the fillet.
  2. Use the minkowski() function to apply a sphere having the radius of the desired fillet to the primitive, effectively applying a fillet to every edge of the primitive. Warning: minkowski() is slow.
  3. Use the difference() function to remove fillets (and excess size) from those edges that don’t need fillets.

This is the process I’ve used designing my footstops so far.

There are free CAD programs that make fillets easy; one is Autodesk 123D Design. I had tried using it a little in the past, but it has its own difficulties.2 Regardless, I decided it was time to try something new.

The Slopes “tripod” for GoPro-sized action cameras is a nice project to duplicate. This comparison shows the result. I’ll print it next week.

I have a lot to learn. :-)


  1. I believe there are fillet libraries I could use, too. 
  2. It’s much harder to be precise. Repetitive tasks (such as the grooves on my footstops) can’t be programmed; each one must be created individually.