E-Class Model Rocket

This is a 3 piece model rocket I designed to take Estes E-class engines. There is a 'launch lug' on the outside of the fin section to fit over a 3mm guide rod which I recommend to keep the trajectory straight during launch. There is also a similarly sized internal lug in the mid section tube for attaching the parachute cord and nose cone. For the parachute cord I use 3mm para-cord as it needs to be quite strong to take the force of the ejection charge. The parachute itself is made from r