More material tests & and some articulation

Whilst I’m waiting to road test the typographic cufflinks, I’m testing a two piece interlocked model called “Spore”.  It’s based on a fungal spore, consisting of a hollow spherical shell with a spiky multi-pointed star sitting loose inside it.  The design is intended to allow the spikes to move in and out of the shell with gravity.  It’s a complex, slightly frivolous idea which could create funky beads for a necklace - but the idea wasn’t really just a design concept, it had some strategic thinking behind it… 

Firstly, I wanted to test out the tolerances / clearances required to print something that was a two piece interlocking design.  This is the basis of chains and machinery, so a natural next step to move beyond the parameters of thickness (walls and supporting wires) and into realm of printer clearances, i.e. how much space do you need between interlocking component 1 & 2 to be printable.  The answer is around 2mm to be safe… which is what I’ve done here.

Secondly, I wanted to experiment with how much of each item I could carve out (using boolean difference calculations in Blender).  The outer shell is a 2mm thick sphere, the inner star is a 2mm thick hollow structure as well.  I then took out more material around seams / joins to leave a consistent 2mm of surface everywhere, but to make as many holes as possible to reduce the volume of the material getting printed, and thus reduce cost.

In that process I hit upon a really pressing 3D modelling issue.  The rotation angles of holes on a spherical surface isn’t like lining-up angles on a 2D one (duh, yes I know it’s obvious) but working out the maths is very complex.  I put the equator / pole holes at 90 degrees to each other, equidistant to make the 6 cardinal points of the star.  The other 8 points of the star fit in the middle of cardinals, making each into a 3 hole cardinal triangle with a hole at each corner and one in the middle of the surface.  The middle hole, bisecting each 90 corner angle sits at 52.5 degrees of rotation x 45 degrees.  I kinda know why, but that was reached by trial and error.  Anyway it worked.

Finally, I wanted to use this to test different materials, especially transparent materials.  I made extra holes in the surface of the spherical shell so you could see the insides (what’s the point of creating a complex 3d printed shape) and also to test out new materials to me - i.e. Almuide and standstone.  

They’ll be arriving in a few weeks, I’m now working on a ceramic 3D type concept… so that’s 3 new collections of print experiments this month.  The next step will be creating commercial executions which will mean getting the production cost down and the final executions sorted.  The aim is to, by April, be hard into selling this stuff…