Have you already realized that you are going to develop a rocket engine?
If you don't understand what powers you want to harness, let it be and buy professional solid rocket motors in a shop, instead of building them yourself and risking the health of you and the people around you.
BTW: H2O2 is more likely to explosively decompose on contact with the wrong material. The USSR lost a R-7 rocket in a massive explosion because somebody just used the wrong welding metal for fixing a leak in a H2O2 tank.
If you are not willed to work with such dangerous technology in a responsible and professional way, don't do it. If you are lucky, you will only loose your hand otherwise. In the worst case, you will not only kill yourself, but also friends and family around you.