MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
hahaaa .... thx for your promt help, i dont know what i am exactly doing , but i have already the machmixer program, i checkt for error nothing found, then i played around with the thickness you said , then i make a new .stl file and it works .... thanks very much, and thanx for the nice present i have yet for may sister !!!!