Issue with Intersect Faces Command

I’m running into a problem when I try to perform an “Intersect
Faces” command. It does not matter whether I call up “With Model” or “With Selection” because in either case, my system goes into a Not Responding cycle and it takes a very long time to recover (if it recovers at all).

This has been a recurring issue. Some cases are more extreme than others. It usually presents as a problem when the model is relatively complex. The image included here as an example has resulted in the hanging system on multiple occasions this evening and has not fully recovered even after waiting for more than an hour.

I was attempting to use the two horizontal planes and the single vertical plane as cutting planes where I intend to delete everything occurring between the horizontal surfaces and everything behind the vertical after completing the Intersect Faces command.

I am concerned as to why the process requires such an inordinate amount of time to complete and why the process is often not successful. Has this been an issue for other SU users or is it just me? Can any of the SU Team Members suggest a reasonable procedure or a workaround for the next time I encounter this issue?

Do you have an example model? I would try it with the plugin s4u Slice

You have Pro. Why not use Pro’s solid tools and do a subtract using rectangular solids ?

Your profile says your running 32-bit 2016 Pro. With the 32-bit edition you have less memory available for such operations. (~3GB)

I suspect that the operation wit shown model involves working with many components iin nested levels.[quote=“jvleearchitects, post:1, topic:21942”]
… and why the process is often not successful.
Not successful in what way? Due to hanging or incomplete geometry in the sliced group?

You must realize that to perform the intersect_with operation, SketchUp must test every face in the selected geometry against every other face. This means the cost of the operation grows as the square of the number of faces, i.e. it explodes if the selections are complex. The solid tools in Pro have no magic solution to this problem, they just handle the post-intersection cleanup automatically for you.

The best answer to this situation is to cull down the amount of geometry selected before invoking intersect with. A person can usually see readily what can or absolutely cannot be involved in the intersection, whereas this is a complicated test for software. So, seek ways to limit what you are intersecting to the minimum and you will see a dramatic improvement.

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One way to get the edge geometry of a slice like that is with a section plane, make group from section.
This gives you all the bits you need to split the various groups and components as needed.

Each of your comments are very much appreciated, guys, so I thank you all. I think that @Wo3Dan and @slbaumgartner were right on point in making me aware of the effects of complex geometry on on this and other types of operations.

On a slightly different point, @DanRathbun, I am currently restricted to the 32 bit version because when I loaded the 64 bit version way back when, my skp files would suddenly vanish into thin air, so I couldn’t get much work done and I reverted back to the 32 bit v. (This issue, which is directly related to an integrated Intel video driver found in my Dell Inspiron unit, has been discussed ad nauseum in previous posts.)

Ultimately, I was able to get the sought after result through performing several intersect commands on selected geometry and conducting several selective delete operations. I freely admit that I still have a lot to learn (even aa a “Sage”) and I should become more familiar with the solid tools.

Anyway, all I was trying to do was to cut up one of my previous models to use in another format where a smaller commercial prototype is needed for a schematic design approach as part of a mixed use development. Here is the end result for those who may be curious:

jvla composite2.skp (982.9 KB)