Super noob: materials and diameter of a body tube

Sorry for making multiple threads but I'm not sure how to delete a thread ._.


I'm building an egg lofter from scratch (we're not allowed kits) for an altitude competition, this is my first time. I've had a few questions that have been bothering me for a while:

- how small the inner diameter of my body tube can be that fits an 18" parachute and allows for a B6-4 motor?


- would it be a good or bad idea to make the body tube out of balsa wood? I don't really care if the actual rocket is destroyed in the process of launching, my goals are just to get the egg as high as possible and then land it without damaging the egg or causing a fire.

Thanks!

Welcome!

Regarding body tubes, the smallest you want is one that fits 18mm motors, or a BT-20 tube.



You don't want to make your body tube out of balsa. I doubt that balsa (on its own) has the necessary hoop strength to contain the ejection event. In other words you would shatter the tube and have rocket confetti as a result.

Greg

This is pretty close to what I made. Heavy paper formed into a cone. 18mm at the bottom and 30-35mm at the top. A plastic egg on top that holds the real egg. The real egg was wrapped in bubble wrap and placed inside the plastic egg. The plastic egg was taped to keep it from coming apart in flight. The plastic egg was then taped to the top of the rocket. The motor was taped into the bottom of the rocket. No launch lug as we used towers. The fins are 1/32 inch plywood from a craft store that are epoxied to the cone body tube. I tied a two foot piece of 100 pound Kevlar to the thrust ring and ran it up the body tube. I used a two foot long piece of elastic tied to the Kevlar. I drilled a couple of holes in the plastic egg and ran a loop of Kevlar through them. I tied the elastic to the loop of Kevlar.

Yeah, you don't want to make it out of balsa.

For small rockets I prefer a strong and sturdy LOC tube, their cheap and they come in large quantities,
also pretty light weight.

Buy a kit and build it on your own, and you'll see how a lot of the pieces work together. Then you will have a better idea of the parts you'll need to buy and how to construct your own rocket. You'll learn a lot that way, I promise.