This week we had a 3D printer in the room, so our plans to stencil paint the apple took a back seat until next week. Instead we printed a dice model and then looked at how to build that model.
The printer we used is a Prusa i3 Mk 2.5. To print a model you import it into a program called a slicer which converts it from a polygon based model into instructions for the printer in how to lay down a series of layers of plastic to build the same approximate shape.
The model we printed was a dice. To do this we used ‘hard surface modelling’ techniques, specifically the use of boolean operators. Boolean operators allow you to take two shapes and make a composite shape that is:
- Difference: The first shape with the second cut-out
- Union: A shape which is the two shape fused together
- Intersect: A shape which is only where the two original shapes overlapped
This technique is powerful, but it results in many N-gons (polygons with more than four sides). N-gons are bad in many circumstances. For example severe distortion may result if :
- If we try to apply smooth shading
- If we try to apply a subsurface modifier
- We later try to distort the mesh, as with an animation
- If we export the model for use in other 3D packages
If none of those apply, hard surface modelling can have its uses.
Here is the instruction video for this week:
The dice model file can be found here.