Patrick,I subscribe to your spring theory. Lately I have switched from copper to,aluminum. Mainly because of elasticity of the metal. I feel like it will build up force and really shoot that flake across the face. I now have a indirect precursor , Ishi stick, amd a couple pressure flakers made from aluminum. If you want to try some they sell a 3ft by 1/4in rod at Lowes for 3$. Hammer the tip for pressure flakers, because it looses it's point fast if ya don't.
