If you’re familiar with 3D printing, you’re probably familiar with the word gyroid. It’s the default fill method for the Prusa slicer and for good reason - gyroids strike a great balance between print speed, structural integrity and filament efficiency.
I’d been thinking about gyroids way more than any normal person every would, and looking for a project to use them in. When we introduced some tiny cherry shrimp into our betta’s aquarium, and they all got eaten within 24 hours, I suddenly had a project: a shrimp hide-away! Shaped like brain coral!
Resources
You can download the SolidWorks surface model and the brain coral (as a Prusa Slicer project file) below. If you want the solid gyroid cube or the brain coral as a STEP file, contact me - they're too big to put on this site!
I searched the internet for a good general-purpose gyroid model that I could use as a base. I found nothing suitable, but I did find this super helpful video by Youtuber @A____11 showing me how to build one in SolidWorks.
Once I had this surface model built, I was able to thicken it by a few millimeters, and then pattern it into a larger gyroid cubic volume. Then, I could make anything into a gyroid by simply performing an intersection (union) between the gyroid cubic and the shape I wanted.
A parametric gyroid surface built in SolidWorks.
The gyroid surface thickened, trimmed and patterned into a cubic volume.
The result: a printable model of two brain coral, with a hidden underground tunnel joining them together. I also trimmed off one side of the model to match the curved glass of my Fluval Flex 15 (so we could peer inside and see how everyone was doing in there). I printed this with a sand-coloured PETG, using Prusa Slicer’s fuzzy skin option.
In this photo, the snails have taken over the brain coral, but trust me, the shrimp do go in there from time to time. Note the underground tunnel giving invertebrates safe passage between the two corals.