The quirk is that although the final geometry looks OK on screen, GH says it is an invalid Brep. Consequently it can’t be Baked, which makes it impossible to print.
What is even more quirky is that everything works Ok with only 1 set of cutters:
Needless to say I’ve tried all sorts of things to get this to work, but I’m stuck. I’m hoping I’ve done something that is causing the Invalid Brep, but so far I’ve been unable to determine what it could be. I’d be most happy if someone could point out an error I’ve made, or point out a different approach that works. invalid.gh (133.1 KB)
By “make the stars a bit shorter” I thought you meant reduce their outside diameter. So I tried that, but it didn’t resolve the problem. The stars are 18 mm outside diameter (OD) and 10 mm inside diameter (ID). I tried 16 and 14 OD but still got Invalid Brep.
However, I did discover that I could get a valid Brep if I reduced the number of columns of stars from the current 14 to 12 or 10. That led me to realize the way I made the cutter shape was incorrect. When I fixed that I got a valid Brep with no problems. So this one turns out to be the infamous
“User Error”.
Mea culpa mea culpa. Mea maxima culpa.
What was the error: When I made the star cutter I thought it would be more efficient to extrude my 2D star shape in both directions, thinking that the cutter would make 2 holes on opposite sides at the same time. But what I missed was that the 360 degree circular array created duplicate/overlapping geometry. To fix it all I had to do was extrude the 2D star shape in one direction only. So this is just another instance of recognizing the benefit of keeping things as simple as possible.
