Hello! Beginner Grasshopper user. I’m a 3D ceramic printer artist and am trying to create forms parametrically.
I want to create gear shapes that stack. Like this:
I created a gh script that creates the rounded teeth of the gear perfectly spaced to fit another set rotated to the midpoints.
I bake these curves and the central curve that the teeth rotate around. In Rhino, I extrude them,cap them and boolean join them (lets call them pregear).
I then bake the teeth curves again, rotate them to center between the points of the pregear. I use the points created in rhino for the points from the divided curve to find the points. I extrude them and make them solid and boolean subtract them from the pregear.
In Rhino I then create a copy and rotate them and raise them about the previous gear.
I really just want to make a wavy curve based on a circle and extrude, rotate and stack.
Is there an easier way?
–Vickie
Yes.
I made this little Starmaker several years ago as a basis for making multi-pointed star shapes for 3D printed vases, bowls, etc. But it will also make gear-like shapes like you showed:
I’ve used this to make a number of 3D printed bowls, vases, etc. Because it uses Nurbs or Interpolated curves the outer shape is not comprised of circular arcs, so if that’s a requirement for you this will not work. Otherwise it’s easy to make lots of other gear-like shapes.
Starmaker.gh (11.9 KB)
2 Likes
Wow! Thank you so much Joseph! You are a star. I need to study what you did. 
Thank you so much Birk! I’ve got to check out your website! Clay extrusion has it’s own set of challenges!
White group adds a second gear and a knob to rotate both gears to check “teeth” alignment.
gears_2024Feb11b.gh (23.6 KB)
P.S. I’m not sure why yet but some values of gear count (always even!) clash teeth… 
Thanks Joseph. It’s actually for a shape of a 3D clay printed vase. Is there a way to make a copy of the gear, move it on top of the existing gear and rotate it?
I made one but did it all manually in Rhino.
I created the gear, copied and rotated it, stacked it above, grouped them and copy pasted it above etc.
I so appreciate your effort in helping me! Thank you!
Yes, of course, that’s easy. What’s the problem?
P.S. This doesn’t resemble your clay printing? And there may be a problem again with my rotation angle?
gears_2024Feb11cc.gh (15.5 KB)
Updated…
3 Likes
No, that’s perfect! 
It matches perfectly for my clay printing! Gravity makes it look different than a pla print. There’s a plugin called planthopper that makes gears but I couldn’t figure out how to make more rounded shaped teeth. Just an FYI. 
I don’t see that? Whatever. Note that I updated my post.
1 Like
