Michael, bye the way, why I can not make chamfer in this situation? When set mesure by one side it works but when by onother or set it manualy it does not work.

Hi Andrei, chamfers or fillets tend to have problems if an entire face or edge is completely consumed away in order to make room for the new piece, as you're trying to do in that case.

For something like that you'd be better off constructing with a triangle to start with rather than a rectangle shape.

- Michael