Skateboard hubs, GH, R7, Cycles

Hi All

Modeled entirely in grasshopper apart from the fillets which I did manually at the end. I had a few challenges getting the transition I wanted underneath the spoke but got there after 7 rewrites of the script.

I am really enjoying the new rendering options in the new wip, without the sss the rubber would look like plastic!



would you be willing share your materials? If so you can post them here, or upload to the materials page here:[0]=im_field_unified_type%3A783&f[1]=im_field_term_reference_type%3A760

see this thread for upload instructions-

As a noob on materials (and rendering) - Why is rubber so difficult to achieve?

I’ve never managed to make rubber look like anything but plastic.

// Rolf

Looks great.
could you share how you made that tires?

Some materials absorb and scatter light to within some distance from the surface. The effect only has to be subtle to be effective. I’ll try post up my experiments today.


H Lukas, it is a revolved profile with cutters flown across the the surface before booling. I used the flow components from the peacock plugin

The funny part with rubber is that is scatter lights in many directions even if it is “black” due to it’s micro pores. So you get a dull highlight on it even if it is shiny.

And another thing is that “black” rubber is just dark gray, but we are used to think of car tires as black, kind of like asfalt, we tent to think of the asfalt color as much darker than it is in reality, so when we replicate what we think we see it just looks wrong. I often see the same things happening in renderings as in drawing, people over do what they think they see and what they notice most. Here’s a typical drawing example:
Notice how the light is well captured, but the face is too big, and the nose is too long with too much focus on the tip, and the mouth is an icon compared to the drawing on the right.


Here is a very simple “rubber” setup:

This is lit with rectangular lights and environment set to 50%
(Note: The front tire is subd while the others are the extracted cage meshes since it is tooo heavy for practical use, loading up raytraced view takes a looong time even with only one subd)

((Edit: I just noticed that the SubD mesh is a 16x16 divided mesh (4 levels of subdivisions) so the rendermesh for that SubD tire is 8 million polygons… The base mesh before converted to a subd is 32 000 polygons, so no wonder it is slow to handle as a subD object if the rendermesh has to be recalculated for every modification)