I’m a newbie to hammer editor, and I’m still in the learning process. I’m creating a team fortress 2 map where there’s supposed to be blown a small hole in the wall with pieces of debris laying around it. However I have not managed this. I’ve tried stuff like deforming a sphere and attempting to use it to carve a hole in the wall (apparently the carve tool stops working when there’s too many polys involved) and I tried to use the clipping tool - which didn’t go too well.
Is there something I’ve overseen? I’d appreciate a quick reply. 
Dan.