I'm doing some booleans and encountered a curiosity. If you un-hide the Box Bottom object you can see what I'm doing. The file attached has the top un-booleaned. If you look at the various objects I've made, you can see I've got a bunch of rectangles then a polyline. I originally tried to loft them all into 1 solid, but that resulted in an object that wouldn't subtract from the box top and bottom. Then I just lofted the rectangles separately from the polyline, since I'm just using them for subtraction. I was able to subtract from the box bottom with the "Wing Subtractor" object which was created by lofting, but I can't subtract from the top. I then went back to the wires and extruded the wing subtractor and it's able to subtract from the box top no problem.

What's the reason that the booleans work in one case but not the other?

Thanks!

Dan

Hi Dan, it's difficult to answer your question very well because I can't seem to repeat the same problem over here...

I tried doing a loft between 2 of the polylines that I thought you were referring to, and then then when I tried to boolean the lofted result from the box top it worked ok for me over here.

Do you possibly have the failure case saved off so that I can load a file with the pieces ready to go to reproduce the boolean failure?


What version of MoI are you running, v2 or the v3 beta?

- Michael

Hi Dan, ok I assume that you're using v2 since when I test in v2 I can see the failure. In v3 it works as it is supposed to though.

So you're running into some bug in geometry handling that's been fixed since v2 was released. There's been a pretty long period of development since v2 was released, there is about 2 and a half years worth of various bug fixes in v3 so it's generally better to use v3 for your work. You can get the current v3 beta here: http://moi3d.com/beta.htm

It's probably caused by a bug that would occasionally incorrectly calculate which side of a solid was the outside region of it. If you select the lofted solid in v2 that doesn't work as a cutter and use Edit > Separate on it followed by Edit > Join that gets its orientation fixed up after that so that it will then boolean out ok. But it's really better to just use v3 instead where it works ok right from the start.

- Michael

Great, thanks! I'll grab v3.

Dan