Every time i use the circle or rectangel clip brushes instead of clipping away polygons it causes the entire image to lose it’s volume and become a skin. If i try to use the clip circle with the alt key to clip a hole into something it only indents the surface and then becomes uneditable…please HELP!!!
For holes you should use the boolean operations of the subtool and remesh.
The clip brushes dont cut, but move poly’s. It took me a lil while to figure out
how to use them effectively. This thread here connected the dots for me,
hope it helps.
http://www.zbrushcentral.com/showthread.php?t=92413&highlight=clip+brushes