Somewhere around 1955 model maker magazine published an article about making a Dan Dare rocket for Jetex. I only had a 35 at the time and not much pocket money, but managed to fly several small rockets, shaped from 1 inch square balsa. We used to drill a hole down the centre of the fuel pellet for the fuse, faster burning for a shorter time and it all worked! Elf and safety, ??? We had fun instead.
Chas