How to Cleanly Brep Join Truss Members?

[Leo13 (Leo)]

Hello there, I did this structure based on pyramids edges, but when I pipe them the joins are not good.

Is there a way that I could turn all this lines of each group in a single brep? I couldn’t do it with solid union

Edges doubt.gh (35.1 KB)

[martinsiegrist]

What’s the goal of this?

FYI 3D printing works with individual overlapping pipes and does not need a single brep.

If you really need this to join into seven single breps, my first suggestion is multipipe and then subd to brep.

If a single mesh is useful, shrinkwrap the nurbs pipes and use round caps on all of them.

[Volker_Rakow]

Here is a start:

Edges doubt VR 1.gh (63.5 KB)

These figures will successfully boolean union. You will have to array them first though.

[Leo13 (Leo)]

I think you achieve it with the 5 and 6th groups, but I didn’t understood the reason of the other groups. It is showing on the 3d model, but the solid union command seems to be empty.

[Volker_Rakow]

Go into document Properties, and set the unit accuracy to, like, 0.000001

[Volker_Rakow]

Here with all the mirroring and arraying, but still in a messy file:

Edges doubt VR 2.gh (76.8 KB)

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Doesn’t work

[martinsiegrist]

In Rhino 9 SR0 2026-9-29 you can get a clean result with a small cheat: sloping pipes are shortened by 0.0005 units and have a radius of 0.0039 instead of 0.004.

The union works if the entire model is scaled with a factor of 1000 and then scaled down afterwards.

solid-union-1000.gh (39.0 KB)

[Volker_Rakow]

It still doesn’t work in Rhino8.

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[martinsiegrist]

Once again it would be interesting to know why the pipes need to be joined into a single brep.

[Volker_Rakow]

It’s possible the slicer will merge these forms, but I’ve taken the unwillingness of Rhino to boolean union them as a personal affront.

[martinsiegrist]

@Volker_Rakow

the slicer will merge these forms

It did merge on these:

Fine Art Selection - Patty Madden

[Volker_Rakow]

Yes, I’ve seen this. Still pretty.