Make a Complete Solid from a Traced Set of Curves

Hi Everyone,

Another newbie question from me…so thanks in advance for the feedback.

I have traced a picture of a boat with curves. I’ve then offset the curves and then extruded the curves to make a solid outline. However, I would like the full centre area to be solid. Is there an easy way to this? You can see this in the top boat that’s in the photo below.

What I have done to try to accomplish this is filled the centre with boxes to fill the space, that is what’s going on in the bottom boat.

The project is going to be a ring, where I’ll wrap the boats around a circle to then 3D print and then cast. Hopefully, I’m explaining myself clear. Please let me know if I’m not. My final ring would look similar to these style but with the boats instead of buildings.

Screen Shot 2020-05-18 at 2.24.59 PM

Here is my Rhino file:
Earnslaw.3dm (5.3 MB)

Thanks very much for any advice!


Basically how Rhino works in this situation is that ‘nested’ curves are extruded together to form a solid with internal holes. You can try a simple example such as a circle inside a square, select them both and extrude>solid, you will see the result is that the circle will be the hole.

So, in this case, draw all your inside details also as closed curves and at the end, select all and extrude together. This will result in a “cookie cutter” kind of shape - flat, no relief on the top surface.

If you want relief - that is to say some of the details show up higher than others, then it’s a bit more complicated - but basically you can build it up out of separate extruded shapes then use Boolean operations to unify or cut holes into the extruded shapes.

Thanks for that.
I’ve just tried the circle in a square and see what you mean.

I’ll try and draw the details inside the boat shape and see how it goes.

What Mitch says (Helvetosaur)…
It may be useful to add that you do not need BooleanUnion persé to unify shapes, exporting your final design to .stl will do that for you. You will have to be mindful that shapes should interfere though, and not just touching and create weak spots in your print.
I prefer to do it that way, since once you have unified them and saved your drawing, it is very difficult to recreate your original building blocks.


P.S. earnslaw…remarkables… not difficult to guess where you are from, or what your favourite region is :slightly_smiling_face: Been there twice, love it.

Just tried that on the actual image and it worked a treat! Thanks for the advice!

Hey Max,
Thanks for that. I see what you mean about being exported together.

Yep, you got it! The Earnslaw. I’m originally from the US but my wife is from NZ and we live about 40 minutes from Queenstown. It’s definitely very quiet there now with no tourists for the next few months at least.


I should qualify that, it is not so much Rhino that unifies the meshes to export those into a .stl, but it is your 3D printing slicer that does it. At least mine does (Cura).


PS. I would love to go there again, but it is a long way from here (Holland). Much closer when I lived in NZ in the 80’s…

Thank you, I’ll remember that.

If you ever make it back, let me know! Will buy you a beer!