I have a complex model (eg the Stanford Dragon) from which I want to derive a multipart (by multipart, I mean maybe 8 or more parts) mould (us.english = mold - I'm going to use 'mould' here, though) for manual resin casting. It occurs to me that the convex hull algorithm may provide some polygons which could be used as a starter for each mould piece.
But the most important thing is to ensure that the model facing sides of each piece will not have (1) any overcut (ie, a clean 'pull') - but even better, be made of polygons whose normals do not deviate too much from the direction of the pull (especially if the mould is going to be rigid, which is what I am planning on). I imagine that detect_planar_patches may help with that.
Needless to say, attention must be also given to those faces whose normals point towards the local centre of the model - typically this is managed by slicing the mould piece coplanar to the normals of those such faces.
I am wondering if anyone has done any work on deriving mould pieces using libraries such as Open3d, or if anyone has further pointers on this.
Adding sprues, I believe, should be reasonably trivial - and I have found some good examples of work done in this.
(I'm really not sure that SO is the right place for this question, but a quick search on SE shows almost all the questions regarding Open3D are on SO.)