Metal Additive 3d Printed Lighthouse
I was lucky to be given an opportunity to print a trinket on a PBF 3d printer. After some brainstorming, I settled on a spiral staircase lighthouse surrounded by waves inside a decorative egg shape that balances on its end like a roly-poly toy. The modeling for this part took a long time and I'm pretty proud of it; I estimate it took ~30 hours total between brainstorming, sketching ideas, writing scripts, fighting Fusion 360, and file prepping for the 3d printer.
The trinket turned out very nice in real life but is somewhat hard to photograph
I went back and forth for a while on how to generate the spirals that go on the outside of the egg, I eventually settled on writing a MATLAB script that generates points along a 3d spiral that can be imported into Fusion 360 because I wasn't able to make shapes that I liked directly in Fusion.
I did the following steps to make the egg shape: import spline from MATLAB, sweep circle along the spline, intersection cut to a surface eclipse shape to get a 3d ribbon surface, thicken ribbon, pattern bodies, revolve/extrusion patchwork, unite bodies, add fillets
Another goal was to keep the CG below the tipping point of the outside ellipse so that the egg stands up on its end in real life. After printing, I needed a bit of sanding for that to actually happen. I tried calculating the tipping point analytically but I realized I could find it fairly easily using clever sketches in Fusion 360 so I did that instead.
The tapered spiral staircase in the lighthouse was surprisingly hard to do in Fusion 360; the directional pattern along a path tool is simply not as powerful as it is in other software. I was able to get it using the sheet metal bend tools but it was a very non-parametric workaround. I also didn't find a great way of making the basalt rocks under the lighthouse outside of patterns, extrusions, and a lot of clicking.
I thought the waves would be the most challenging part to model, but they turned out to be pretty easy, albeit time-consuming, using the freeform tool in Fusion 360. I used frozen squares on the outside to make sure that the connection to the rest of the egg remained flat.
