Although I don’t have a styrofoam box yet I decided to start making a parachute that will safely carry my equipment back to the ground after the balloon flight. The material I used is an ordinary garbage bag. I cut open the bag so it’s a big flat sheet of plastic, then I took half the bag and attached strings to the corners and then attached a box to it. I tried to simulate the weight of the final box that would then go to space, so approximately 500 – 600 grams, maybe less. So my first parachute had a square shape and had side lengths of 53 cm’s. I was already pretty sure that it was too small but I still tried it and threw it off my house’s roof and it actually did brake down the fall, but not to my satisfaction.
Next I searched the internet for any kind of model rocket parachute size calculator and I got lucky. The program told me I needed a circular parachute with a diameter of 129 cm’s. What I decided to do was find out what surface this circle would have and made a square with the same surface. The second parachute now had the size of two cut open garbage bags with side lengths of 106 cm’s. But before I got to test my second parachute it started raining and I had to stop testing for today. But parachute 2.0 looks very promising.