Good day.

I need to make this fin into a solid shape to 3d print.

What would be the best way close it up and make it a solid?

Thank you!

you want close the background(s) or give a thickness to this ribbon, or make the complete figure as a volume ?

The shape should be the thickness of the ribbon

Dear Matadem,
From my experience in this kind of Fin shape that you want to create as a closed 3D solid, I am sending you this picture to understand how you can do it plus the result of it.
Hope you will manage to do it.

Hi Matadem, the best way is to model it as a solid block that is cut, rather than modeling it as a 3D ribbon that needs to be filled.

For a curve like this one here:


Which when viewed from the top has a 2D silhouette profile:


you don't want to be directly constructing the 3D version of that curve - instead you want to have a 2D profile curve which cuts an extended solid block.

So for your case here the extended solid block would be an extrusion of this planar profile curve:





Then select the extended block and use boolean difference to cut it with these 2D profile curves:



That will cut up the solid into several solid pieces:


Discard the outside pieces leaving the inner one that you want for the result:


The main thing is that when you form a shape as a solid that is cut by 2d profile curves, the resulting pieces will already be solids with "side walls" left behind from the cutting curves so it's already filled in.

- Michael

Dear Mr Gibson,

This is better then mine because I follow your method and it was very good, thanks a lot.

Also if you make the x/y plane profile to be a closed curve then you can generate the result with boolean intersection without needing to discard anything:





- Michael