Puzzle Cake custom supports (soluble)

thingiverse

I stumbled upon the puzzle when purchasing it for my dad last Christmas and I found it absolutely fascinating. As I worked out the solution, I came up with the idea to create a 3D model and print it. Unfortunately, Thingiverse already had a model available, thanks to @tapka. Since I have multiple multi-material printers, I thought that using soluble material would result in perfect parts by printing supported areas with good quality. The soluble material I'm working with is BVOH, which is somewhat pricey but still suitable for this application despite some caveats. I first attempted to use Prusa Slicer 2 and set the BVOH as the support interface material. However, this didn't work out well because the BVOH failed to stick to the sparse PLA support structure, causing a messy blob of BVOH to move around with the printhead during printing. I'm unsure if this is due to the fact that the BVOH has been unused for nearly a year or something else. It appears that small surfaces are difficult for BVOH to adhere to, but larger areas work fine. Given that configuring the slicer to do things properly probably won't work, I decided to design my own supports that function flawlessly with PLA and BVOH. These custom supports achieve several goals: - They provide a solid base for BVOH to stick to - They offer a 'perfect' base for the supported part as the BVOH is printed in regular model pattern, not support mode pattern - They limit BVOH usage to only a few layers where it's needed. I use single nozzle-multi extruder setups, so each material change requires a certain amount of purge which amounts to waste - They satisfy my curiosity about proper soluble usage OpenSCAD source: https://github.com/spegelius/3DModels/tree/master/Puzzle_Cake_remix