Hi, I have an stl file of a head (see attached) and i want to design a helmet for it with the shape of the picture(without the holes).
I have a pattern that i have done in fusion 360 and i want to place it in that helmet to work as a liner like you can see in the section drawing. But i want to try different patterns so i am looking for a method to place patterns there. Consider that i want to later 3d print (non planar printing) it so it has to be according to that. Thanks to anyone that spends time in helping me
Hi Cristina - since you have an STL file of the head here’s how I suggest you proceed:
Import the STL file into Rhino, and then Internalize it as a single Geometry object in GH.
Create a canted plane that separates the head into 2 parts: everything that you want the helmet to cover, and everything else. Forget about the second part.
Make a series of vertical planes that intersect with the top part of the head and get their intersection curves.
Use these curves to make a closed Loft surface. This should look like the chopped off top of the head. If some of the curves include parts you don’t care about (like the tops of the ears) use negative values for Extend Curve to remove them.
Use whatever method you want to create the outer helmet shape above/around this Loft surface.
Use the surface edges from #4 and #5 to make a surface (I typically use a Ruled surface for this) to connect #4 & #5. If you are lucky this will result in a Closed Brep you can export from Rhino as a new STL file and print with a standard 2 1/2 D printer.
Even if #6 does not produce a Closed Brep you can still print it if you correct the resulting STL errors with something like Netfabb.
If you have access to a 3, 4, or 5 axis milling machine, or an appropriately equipped Kuka robot, you could mill the complete helmet with smooth 3D curves all over.
