Greetings lupiro, From what I can tell you didn't do anything wrong, so as triplus mentioned I'd suggest you upgrade your FreeCAD version. What you're using is outdated and relatively weak. I deleted Cut from both of your models and did the boolean differences again with no problems. 20140409e_cut_d...

One other thing, you would do yourself a big favor by upgrading your version of FreeCAD. I just noticed this post which will be of help to you.

Greetings picad, Sketch003 from which you created Extrude has no constraints. Each endpoint should be constrained coincident to the endpoint of the adjacent segment. Also, delete "Extrude" by clicking on it in the tree view and selecting delete. After you've got the endpoints constrained c...

Thanks bejant. I must get registered on Mantis so that I can pester the developers there! Before you file a ticket I'd suggest waiting a day or so to give the dev's a chance to chime in on the forum. And who knows, as has happened many times before (and even earlier in this thread) that issue might...

Greetings fireclown,
I don't think 32 bit FreeCAD on a 64 bit OS is the problem.

Is this problem with the CAD navigation style?

Try right-clicking on a blank portion of the 3D window, then click Navigation Styles, and select CAD navigation if it is not already selected.

Greetings tmoore, To add to triplus' explanation: The problem is that there is nothing contiguous between Pad and Sketch001. In other words, Sketch 001 is off in space; here's a view of both Sketches looking down from the top: 20140409c_tmoore.jpg Try this: Select Pad001 in the tree view and delete ...

I had to use a FreeCAD version with a newer version of OCC to get this to work. You can get it here. It's in .7z zipped format. Download it and move it to a folder of your liking (mine is "FreeCAD 3343"), unzip it, and in that folder look for a subfolder named "bin". Navigate to ...

I'll have a look and will post back...

I agree that it works fine with no crashes. The point I was trying to make to triplus is that you can break a model by changing anything in an underlying sketch. Not only by adding and deleting things or changing references to external geometry but by moving things. Ok, I was thinking that you were...

Well, first off, Normandc is the person to ask for help about this. I seem to remember he once modeled a birthday cake, including the candle, for FreeCAD's (10th?) birthday. But did you know that what you really made is an upside-down cake? Anyway. I moved the torus to Z = 5mm, so the Y=axis center-...