Boolean operation failing


#1

Traverse graph with surface for intersection.3dm (1.7 MB)

I’m having difficulty getting a surface to boolean with an object. Essentially I want the curved surface to subtract away the bottom of the object so that the bottom of the object is shaped like that surface. This means that the parts of the surface extending out around the object need to be removed also. What I’ve been trying to do is a boolean differance operation but it keeps failing. I’m quite new to Rhino but I’ve done some Googling and checked a few things that seem to be potential problem causers e.g. I corrected the normals of the cutting surface so that they point towards the object. However there are other problems such as I think the object is currently not a solid or functioning as such. I tried CreateSolid but it couldn’t be done. I’ve uploaded the file and if anyone can get this to work I’ll be incredibly, enormously grateful. The cutting surface is there in the position I want and there is an object below it that can be ignored (I took the cutting surface from it).


(Pascal Golay) #2

Hi Alex- on the the surfaces below the wiggly/angly surfaces are sort of messy- I can’t tell what you intend there but there are surfaces that start inside and end up outside in the boxy part… I guess you want all that just to be a box extending down from the angly surfaces and cut off by the cutter surface, correct?

-Pascal


#3

Update: I’ve managed to get the curved surface to boolean off the base of the model. Now I just need to remove the parts of the curved surface that extend beyond the object. I’ve tried to boolean difference with the object as the set of surfaces to cut with but the operation fails.

When you click, everything will be selected initially but then clicking on the curved surface will allow you to select it. You’ll also see that the object is Group 03.

Any help is greatly appreciated.

Traverse graph with surface for intersection - Boolean differenced.3dm (1.9 MB)


#4

Hi Pascal,
I don’t follow what you’ve said here, but I just uploaded an updated version where I’ve managed to boolean off the base of the object as I wanted, so you’ll see what I meant. However the curved surface extends beyond the object, which I don’t want. I’ve tried to boolean difference it away but it fails. Please if you could read my second post and take a look at the updated post, I’d be really grateful.


(Pascal Golay) #5

You can make it work more or less, by using Flip on the big surface before the Boolean. But this is a messy thing - ExtractSrf the big surface and hide everything else- see what I mean? The inputs are just too imprecise - for example the end points on the input curves to your loft are not in line- it looks like the intention is that they should be so that the vertical lines viewed in Front would be truly vertical and parallel, but they are not.

Traverse graph with surface for intersection_PG.3dm (294.1 KB)

Try working with the attached.

-Pascal