why solid union cannot work sometimes

hi guys

I have one big problem which has confused me for a long time.

i have lots of conical shape intersect with each other

and i try to use solid union to get the intersected geometry

but sometimes i really dont know why it doesnt work!

since there are quite a lot shapes to deal with, i cannot do the solid union manually one by one

both in terms of complex geometry and time-consuming.

sometimes it works and turn out the geometry like this

since this step is super critical in our project, i have to solve, but i really have no idea

can someone help me out?

thanks a lot

Attachments:

test solid union.3dm, 84 KB
test solid union.ghx, 1.1 MB

Replies to This Discussion

Permalink Reply by David Rutten on December 8, 2010 at 9:48am

Hi hurriarc,

does the boolean work if you bake the geometry and use the _BooleanUnion command in Rhino?

--
David Rutten
david@mcneel.com
Seattle, WA

Permalink Reply by hurriarc on December 8, 2010 at 1:13pm

thanks a lot, David.

It works by using the _BooleanUnion command in Rhino.

do you know why it turned out not working properly in grasshopper?

cheers

Permalink Reply by David Rutten on December 8, 2010 at 2:58pm

No I don't. We'll look into it.

--
David Rutten
david@mcneel.com
Seattle, WA

Permalink Reply by Katerina Dimitrova on February 23, 2016 at 9:05am

Hi David,

I have the same problem, but here the BooleanUnion command in Rhino didn't work either. Any other suggestions?

Permalink Reply by Norbert on February 23, 2016 at 10:01am

Hi Katarina,

I am dealing a long time with this problem. I try the following order:

1. Try to change the tolerance.

2. Move the on set of geometry a little (0.002 mm or 0.01 mm).

3. Try the boolean operation in rhino.

4. Intersect the sets by hand, look carefully at the intersection curve (clean it), trim the solids manually away and join the leftover together. Sounds more work than it finally is.

To me it looks like the problems occurs if one edge runs into another one.

Good luck, Norbert.

Permalink Reply by Katerina Dimitrova on February 23, 2016 at 12:11pm

Thanks a lot Norbert! I'll try all those steps, hope some of them will fix the problem.

Permalink Reply by Nik Willmore on February 23, 2016 at 1:30pm

See here a way to visualize all the intersections at once, for troubleshooting:

http://www.grasshopper3d.com/forum/topics/solid-difference-not-work...

Permalink Reply by Fred Becquelin on December 8, 2010 at 1:46pm

Hi!
Yes, it's an issue I've had so many times I don't even try tu use booleans anymore... Also, if you can fix it, it'd be nice optimize it for "massive" unions; some kind of loop (I don't know anything of any language)

btw, nice pics hurriarc!

Permalink Reply by Astro/Naught on December 8, 2010 at 7:12pm

I have had issues in a few instances where the solid union simply does not do the job in grasshopper but does work in Rhino. I thought I was the only one

Permalink Reply by hurriarc on January 8, 2011 at 12:43pm

thanks a lot for ur help.

I think the tolerance is one of the main reason that results in error during booleanunion

so the vb component helps a lot!

Permalink Reply by Greg J on January 8, 2011 at 6:08pm

wow, first time I've seen this thread.

I've been dealing with this issue and not coming up with any answers.

Driving me crazy also.

Permalink Reply by Jonathan Sheridan on September 25, 2012 at 12:57am

I wonder if this could be solved by joining each part individually?... It works in Rhino.

I know that I have a problem that could be solved with this approach. Therfore I ask: How do I join lots of items to a block for example i.e. attaching one item at a time by using Grasshopper components or lists?