Been trying to knap but it has been quite the challenge. have tried some on a piece of commode and on some glass. The glass sure makes for a bad mess of slivers. I totally struggle trying to use my hands to hold the piece and I need to make a better flaker for my jig that I made. I have done the best with the jig so far. And yes, broke the only piece that had any hope of looking remotely like a head. I haven't got the copper nails to work with or the plastic handles/rods to make them with. I have just made some out of materials that I had on hand. the wife comes and looks at the blood that seems to be on everything and says that I am nuts LOL. I have to be careful with the pressure flaker because of the pressure that you have to use, I can feel it some in my eye with the 30 something stitches in it. So I need to make a longer flaker for better leverage with the jig. I am using my magnifying lens with the 8" circle light to see what I am doing. You guys on You Tube make it look so easy. I want to make an indirect percussion that doesn't have to go under your leg to work with a jig if possible. Jerry