I built a rocket out of a cigar tube and put a C6-4 engine in it. Im sure you know but for everyone who dosen't, the first two numbers refer to the power and the last number refers to the number of seconds before the end charge. if the number is 0 then there is no endcharge. I made two cigar rockets. the first one I launched with a b4-0 and it was good, but I wanted to blow up the other one so I used th c6-4 and CA glued it in place. The engine just flew out the end and caused no damage to the tube at all, so im sure you'll be fine. Your pretty responsible of you to start with A engines, I remember building a rocket with my dad when I was young and the box said to use b engine and an A engine for the first flight. Well we used a D engine for the first flight, and even though we