hey guys,\r\nI have problem with extrude tool, when I try to give thickness to my model and try to use blue arrow (z axis) and extrude it out selected faces, extrusion is happening in 2 sides I mean (extrude in & extrude out).my model starts to be thickened from in and out. please see attached photo. I don't want extrude to act inside of the helm. what should I do? I use some YouTube videos to learn Maya. I do exactly what the guy does in video but mine doesn't work the same way. second attached photo is YouTube tutorial. I always have this problem with extrude. Any help would be appreciated. Thanks in advance.