gravitrax canon lifter

This thing is a "Cannon" to lift Gravitrax steel marbles up 15cm, giving them more potential energy to spend along the track that follows.If you have played Gravitrax you know that the most recurring question you will be asking yourself is "How do I gain more height?"Height is important because it all works on gravity pulling the marbles down and spending their potential energy doing tricks and gaining speed.I know there are solutions out there, Gravitrax stock lift, for example, but the idea of designing an actual shooting cannon was too tempting to resist!The principle is very simple... A percussor held in a "loaded" position by a trigger that gets freed when the marble falls into the cannon. The percussor is loaded by 2 rubber bands. The rubber bands I personally used are the replacement ones you will find in the stock Gravitrax "Catapult" expansion. There are plenty of replacements, the Catapult only needs 1, so the Cannon can use another 2. I believ