rocket weight tests

4th August 2019 at 9:15pm
completely home-brew rockets engineering observations test
Word Count: 317

Before we build our own rocket we need to ask – will it be too heavy?

We can estimate the weight and compare it to the kit rockets we've been using.

ComponentKit weightOur weightDifference
nose5.0g4.5g-0.5g
body3.6g22cm x 0.4g/cm = 8.8g+5.2g
fins1.3g3 x 2.1g = 6.3g+5.0g
recovery system1.9g??????
Total11.8g> 19.6g> 9.8

Thoughts

  • Ours weighs at least 2/3 more than the kit. Is this a problem?
    • If so, what could we do about it?
    • If not, how do we know it's not?
  • How will this effect the balance?
    • Our nose is slightly lighter, and our fins are significantly heavier.
    • This shifts the balance in the bad direction
  • The difference is about evenly split between the nose and the body.

Conclusions

  • The total weight isn't necessarily a problem
  • The balance shift probably is
  • We should probably focus on the fins
    • Each fin is 1.9g paper and ~0.3g glue
    • We could use single paper, cutting the weight to about 0.6g per fin
    • We could use plastic
    • We could use Styrofoam
    • We could use foam core
    • We could use balsa l(like the kits)
  • The tubes are not as big of an issue but may still be worth addressing
    • We should sacrifice one of the kit tubes and see how strong they are. We could also disect it.
      • Non-destructive examination by shining a bright light gives...confusing data. It shows sign that they were engineered.
    • We might get away with only two layers (cutting the weight to about 4.4g)
    • Parchment paper might be a good idea (will you just give up!!?!)
    • We might even get away with only a single layer (with a tiny overlap? How would that work? Spiraling!)