Hi,

I make a rectangle which then I offset inwards, then I draw another rectangle inside this construction, the width of the small rectangle equals the width of the larger one with the offset. the idea is to make a window with divisions.

when I boolean the 3 rectangles, one piece is missing.

I can work around it by first extruding the outer frame and the small rectangle and then boolean them together, but I wonder if this is an error or just because the program does not know what is inside and what is outside?

tnx
wim