Wow what a great feedback guys! Looks like silhouette boundary solves the problem. That's exactly what I meant! Now finally moving on with my thesis! Thank you!

Hi Guys, I'm having an issue in mastercam x7 when defining chains for rough pocket machining. There is an option to choose containment chain, where as I've seen on some tutorials, is a possibility to pick stock material as a chain and machine everything all around previously indicated model surface. For some reason my mastercam is not recognizing stock as a possible containment chain and I can't go any further with machining my part. Any ideas how to fix it?