Designing voxel models

Designing volumetric propertiea is quite a difficult task in the current software culture. None of the standard CAD programs work with volumetric specifications (in my limited experience).

Gladly there is Autodesk Monolith. You can import an STL, which is converted into a voxel field with densities of 100% inside the STL and 0% outside.

You can then model your properties by painting the voxel colors; you need to uncheck geometry so that you only affect the voxel colors, not the densities.

Set the visualization alpha really low so that you can easily see what’s going on inside the model.

When you’re ready go to the rasterization tab and select to only export the material ratio. You can then export the voxel model to a sequence of images. The image lightness encodes the material ratio and the alpha channel encodes the material density.

This is a really nice tool if you want to draw volumetric material property specifications. It can be used to specify an image sequence to be used in Cura as a density voxel model for 3d printing with FDM.

Support Brim

Last week I started a print in TPU with PLA support, but the support failed because it doesn’t adhere to the brim which I printed in TPU.

To fix my print I used hotglue to (melt the support and) glue the support to the brim. That hack worked!

In the meantime I decided that this behaviour should be improved. I wrote a feature which replaces the regions under support with a brim printed in the same material as the support. That way the adhesion of the support to the buildplate is improved and the brim region next to the object is still satisfied – albeit with 2 different materials.

Robust Connect Infill Polygons

The features to connect infill polygons together in order to get continuous extrusion for all infill patterns was not very stable. It is quite hard to reliably find a location where you can cross to another polygon and it often happens that that crossing doesn’t permit a crossing back, so that the bridge between two polygons cannot be created. The implementation is now improved.

Whereas it used to connect 65% of all polygons before it now connects 99.5%.

Hopefully this improvement can be merged to Ultimaker Cura shortly.

Big gray scale project

Today I had a talk with Alessandro Sambini, Joris v Tubbergen and others about an art project which is centered around creating a life-size statue of a person using my gray-scale halftoning technique.

We need to do some initial experiments to see how well the techniques adapt to higher layer heights and bigger nozzle sizes to see whether the project will go through, but I have full confidence.