Looking at building an 8 inch diameter rocket. (first post)

Discussion in 'Techniques' started by wdnoble1979, Oct 19, 2019.

Help Support The Rocketry Forum by donating:

  1. Oct 19, 2019 #1

    wdnoble1979

    wdnoble1979

    wdnoble1979

    New Member

    Joined:
    Oct 19, 2019
    Messages:
    2
    Likes Received:
    0
    Gender:
    Male
    I have built 4 inch diameter cardboard rockets with H thru J motors. A friend and I are looking at building a rocket that meets the specifications for the 2019-2020 NASA SLI. Have a friend who is designing a payload that requires an 8 inch diameter. I am sure there are lots of differences from what I have built before just looking suggestions on what that might be.
     
  2. Oct 19, 2019 #2

    Bat-mite

    Bat-mite

    Bat-mite

    Rocketeer in MD

    Joined:
    Dec 5, 2013
    Messages:
    10,177
    Likes Received:
    1,074
    Gender:
    Male
    Location:
    Maryland
    You still thinking cardboard and wood, or would you be moving up to CF or FG? There are other options, too.
     
  3. Oct 20, 2019 #3

    Nytrunner

    Nytrunner

    Nytrunner

    Master of Rivets

    Joined:
    Oct 15, 2016
    Messages:
    5,141
    Likes Received:
    1,074
    Gender:
    Male
    Location:
    Huntsville AL
    Larger diameter-> more mass -> punchier motors required + higher recovery forces experienced

    Landing may put more stress on your rocket than flying it
     
  4. Oct 20, 2019 #4

    timbucktoo

    timbucktoo

    timbucktoo

    Well-Known Member Staff Member Global Mod

    Joined:
    Jun 13, 2014
    Messages:
    5,975
    Likes Received:
    527
    Gender:
    Male
    Location:
    Cocoa Beach
    A team from Florida college (FIT) a few years ago built theirs out of blue tube. It was 7.5” payload.
     
  5. Oct 20, 2019 #5

    Nytrunner

    Nytrunner

    Nytrunner

    Master of Rivets

    Joined:
    Oct 15, 2016
    Messages:
    5,141
    Likes Received:
    1,074
    Gender:
    Male
    Location:
    Huntsville AL
    Yup, we see all sorts of airframes when conducting the flight readiness reviews each year.
    Fiberglass, carbon fiber (commercial and homemade), Blue tube, phenolic, glassed cardboard, and even Chattanooga with their 4' cardboard entry on an I600 this year ("we didn't need anything stronger")
     
  6. Oct 20, 2019 #6

    GaryT

    GaryT

    GaryT

    Sponsor TRF Sponsor

    Joined:
    Jan 19, 2009
    Messages:
    2,032
    Likes Received:
    75
    Gender:
    Male
    Location:
    Guilford CT
    This is my 8" Albatross a rocket I designed and built. Although fun to fly as I've flown M N's & O's in it they are a Beast! of a rocket to handle. Then you have the transport, load onto the Unistrut rail and especially recover! It, it also gets pretty expensive just to outfit it to fly, heck the chute alone will run you between 2-300.00. Just a bit of info before you embark on your build, good luck.

    [​IMG]
    [​IMG]
    [​IMG]

    EX O3400 Blue Diablo
     
  7. Oct 20, 2019 #7

    OverTheTop

    OverTheTop

    OverTheTop

    Forum Supporter TRF Supporter

    Joined:
    Jul 10, 2007
    Messages:
    2,985
    Likes Received:
    599
    Gender:
    Male
    Location:
    Melbourne Australia
    markg likes this.
  8. Oct 20, 2019 #8

    dhbarr

    dhbarr

    dhbarr

    Amateur Professional TRF Supporter

    Joined:
    Jan 30, 2016
    Messages:
    5,629
    Likes Received:
    568
    Does the payload need to be enclosed?

    Do you want to have the entire airframe match the diameter of the payload?

    Are you familiar with egg lofters?
     
    jrkennedy2 likes this.
  9. Oct 20, 2019 #9

    tfish

    tfish

    tfish

    Forum Supporter TRF Supporter

    Joined:
    Dec 8, 2009
    Messages:
    2,380
    Likes Received:
    325
    IIRC...NASA SLI....the posters stated event is limited to L motors.

    Tony
     
  10. Oct 20, 2019 #10

    OverTheTop

    OverTheTop

    OverTheTop

    Forum Supporter TRF Supporter

    Joined:
    Jul 10, 2007
    Messages:
    2,985
    Likes Received:
    599
    Gender:
    Male
    Location:
    Melbourne Australia
    How many are they allowed to use ;).
     

Share This Page