CAD design
A CAD program like Fusion 360 is the link between the idea and its execution. From sketch to model to object.
A few tips from my process:
Keep the idea simple. My original idea was a spherical speaker. On legs, that's it. Later, I added the waveguide made of wood. And I thought it would be cool if the shape were more like a zeppelin. Because the spherical shape is also very unique and monolithic, it remained as the model for the woofer.
If you start casting in silicone, you quickly discover that it's a very expensive material. Normally, you build walls as formwork for the casting. Those walls aren't easy to make in themselves; some people use LEGO or ready-made elements with clamps, but I just don't think that's great. That's why I invested some extra design and printing time for formwork that also uses less silicone. I also measured the silicone volume precisely so I didn't waste anything.
When casting silicone, you have to keep in mind that if you later cast it in plaster, the mold should be upside down. There must be absolutely no tension on your mold when pouring plaster into it, otherwise you'll get warps. So pour on a horizontal surface, all the way to the top edge of your formwork, so you won't get any sagging when pouring the plaster.
Most parts required around 1.5L of silicone, but larger pieces sometimes required nearly 4 liters.
To create a structurally sound mold, you should ideally work with a wall thickness of at least 4cm, but I wasn't always successful in achieving this. This may have reduced my suction (water absorption) slightly. And to ensure a precise seal, I made keyholes, flattened spheres of around 2-2.5cm.
The toolpaths (G-code for the CNC) also come from my CAD program. Things like feed rate and stepover all depend on the material, your CNC, and the router bit you're using. I use solid wood, which I select for each set from Amsterdamse Fijnhout. At the time of writing, I recently purchased a beautiful piece of elm, a typical Amsterdam tree.
In short: a good CAD program is essential for realizing a new product. It streamlines your production process and you can rely on it in all sorts of ways.
Good luck with your dream product! For questions or feedback, please send me a message via the contactpage!