Quick and dirty 5 minutes craft: Draw a rough shape, define the contact surfaces & load, click run, and get the optimized shape. The last step is converting the output to a printable shape and running one more simulation to double-check it is strong enough.
This particular holder is a filament spool holder designed to be loaded with up to 5.5kg of filament (1x2.5kg, 3x1kg).
I imagine the “optimized” there means it has the maximum weight support with the minimum amount of filament.
This shape certainly beats a triangle with only the walls or with just a bit of infill. And it surely takes less filament than one with near to 100% of infill.
Nature loves triangles.
https://en.wikipedia.org/wiki/Michell_structures
The thing with 3D printing is that it is usually stronger and uses less filament when you do a full shape without holes.
These shapes work well with conventional manufacturing, but 3D printing is different because it is mostly hollow on the inside
Less filament, yes. But it’s almost always weaker.
It’s common to add holes so you get a stronger part.
I don’t follow you. Look at the photo, the thing is made of triangles. It’s the best shape. So I wonder, why use more than just one? Why make the shape require more than one triangle?
More than likely the static supports used in the software were in the locations you see now,1 for spool and other’s bellow on the rail. They said “draw a rough shape” as a step, so that dictated the shape.
If the static loads were placed at even height you would end up more triangle like or more of a truss. Depends shown many iterations were used also.
Hum, ok, I misunderstood you.
Your 1 triangle will need the inclination similar to that middle segment of the bottom side of the piece. I will be huge.