Joining Intersecting Curves

Hello all, I am creating a low poly wireframe head to 3D Print. I have chosen to manually create the shape of the low poly wireframe head using curves and would like to pipe it as I am going to thread a nylon string through.

I have tried the piping process but it is not smooth because the curves are not joined properly. I have checked and ensured all points are connected to each other but when I explode everything and use the join tool, it creates closed and open curves. I was wondering if there are any methods of joining intersecting curves together as I believe the problem is that curves do not branch out.

Thank you!

Well, having done this sort of thing in Rhino I would say you are likely not going to have much success getting the joints all trimmed to each other and closed up into a closed polysurface. Too many pipes coming together at one spot for Rhino to deal with well.

What I usually do to cheat in this situation is explode all the curves into single lines, and make sure you delete all the duplicates. Then select them all, and run CrvStart and CrvEnd. That will create points at the start and ends of all the lines. SelDup to get rid of the duplicate points.

Then place a sphere that is a little bigger in diameter than your pipes at each point - there is a script to do this below. Last, pipe all the curves. Then you can try to BooleanUnion the pipes and the spheres together. You might work small sections at a time, it generally works better than all at once. The spheres will ensure that there is a relatively clean, closed joint, and they will be hardly noticeable… (896 Bytes)

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Thank you Helvetosaur! I’ll try it out now! :ok_man:

Hi Helvetosaur! I am in the midst of BooleanUnion-ing them slowly! Because I am threading a nylon string through, I’d like to clarify if the pipes will be clear in the middle? Thank you!

No, the above will make everything solid. I didn’t understand that the threads need to go through the pipes. That will be somewhat complicated… I don’t know how you are going to 3D print them that way, but…

You could do the process twice. Once with pipes/spheres of the inner diameter (the holes in the tubes); once with the pipes and spheres of the outer diameter. Then you would need to BooleanDifference the inner from the outer to get the hollow shell. It might be a bit tricky.

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That sounds like a way! Thank you for all your help!