Jupiter C/Juno I - New Scratch Build

Discussion in 'Low Power Rocketry (LPR)' started by ToneDeafJunior, Jul 5, 2018.

Help Support The Rocketry Forum by donating:

  1. Jul 5, 2018 #1

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    I'm building a scratch Jupiter C using a 66 mm tube for the booster. I'm using Peter's book for my scale dims. From the original Estes kit with the 2 inch ST-20 tube, I'll need to increase the fin dimensions by 29.4%. 24mm motor mount is complete and working on the ply fins now. Hope it will not be too heavy to fly on D12-3's. 2-3 hundred feet is fine for me. Doing my calculations, the upper stage housing should be 38mm in diameter if my maf is correct. I think I'll just use a BT-55 or 33mm tube for that. Any suggestions what to use for the actual satellite or corrections I should know about?
    Fin Dims.jpg Motor Mount.jpg
     
  2. Jul 5, 2018 #2

    milehigh

    milehigh

    milehigh

    Well-Known Member

    Joined:
    Apr 26, 2016
    Messages:
    246
    Likes Received:
    10
    My suggestion is to get access to a wood-turning lathe, and turn the entire payload/nose section as one piece out of a balsa block. Such a balsa block is available at Hobby Lobby ( 3" x3" x 12" ). I would go with a piece of dowel for the 4th stage and satellite, possibly making it so that it is removable for flight. That little piece is easy to break off. An alternative would be to rig the payload section so that it can hang base-down under the parachute.
    A D12 engine would probably get the whole affair into the air like you said -at a 200-300 foot altitude. You might consider the mount for use of the 24mm E motor, and use a spacer tube for D engine flight.
    Back in the 70s, I had a Hawk Jupiter C static plastic model that I retro-converted for flight. With enough added nose weight, it flew very nicely on a C6-3 motor! Funny thing is that I accomplished the plastic model conversion before I noticed that G. Harry Stine had an article about the same in one of his 'Old Rocketeer columns in Model Rocketry magazine. I could have really benefitted from that article, had I known!
    Anyway, good luck with your build.
     
  3. Jul 6, 2018 #3

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    I saw those old Hawk models and thought they were cool. I just wish they were bigger. As for the upper stages, I don't have or know anyone with a lathe so that's out for me. I did order a BT-58 tube today so the upper stage will be in scale. I also worked on the scale fins tonight. They are coming along nicely. I taped the 4 fins together and used my sled on the table saw to dado away the extra material. I wonder with them being plywood if I should seal them with CWF and sand. Thoughts?
     

    Attached Files:

    • 1 .jpg
      1 .jpg
      File size:
      186.7 KB
      Views:
      90
    • 2.jpg
      2.jpg
      File size:
      106.6 KB
      Views:
      97
    • 3.jpg
      3.jpg
      File size:
      212 KB
      Views:
      105
    • 4.jpg
      4.jpg
      File size:
      183.8 KB
      Views:
      91
  4. Jul 12, 2018 #4

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Fins are on the rocket after CWF and sanding. The finished model seems to be 78.8cm tall if my maf is correct. Just over 31 inches. I'm going to start shaping the nose cone with a stock cone from eRockets and cut down the second 66mm tube for final booster height.
    1.jpg 2.jpg 3.jpg
     
  5. Jul 13, 2018 #5

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Shaped the nose cone, applied CWF and a first sanding. Started with the upper stage too. Had to cut down a tube to 33mm. It also took several tries to get the center of the dowel but, I got it. Used a pencil for the satallite. Shaped the pieces on a belt and disc sander and did 1.jpg 2.jpg 3.jpg an initial prime.
     
    lakeroadster likes this.
  6. Jul 13, 2018 #6

    lakeroadster

    lakeroadster

    lakeroadster

    Lone Wolf... No Club TRF Supporter

    Joined:
    Mar 3, 2018
    Messages:
    766
    Likes Received:
    71
    Gender:
    Male
    Location:
    Central Colorado
    Thanks for documenting the build..

    Love the ole pencil and sander trick. Did you turn it by hand or chuck the pencil into a drill

    It's a now or later thing. I'd seal the edges (except root) with CA, and the faces with CWF.
     
    Last edited: Jul 13, 2018
  7. Jul 13, 2018 #7

    kuririn

    kuririn

    kuririn

    Well-Known Member

    Joined:
    Oct 3, 2016
    Messages:
    801
    Likes Received:
    87
    Very creative work, C.L. Love the fin work, and the nose cone and Explorer satellite are works of art. FYI, a 33 mm tube is the same size as a BT-55 (for future reference).
     
  8. Jul 13, 2018 #8

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Thanks for the atta-boy Kuririn. Evidently my math was wrong at the beginning. I thought I needed a 38mm tube for the upper stage. I had it cut and mildly taped together and something just did not look right. It was the diameter of the tube. I have bt-55 tubes but, since I had already cut the ST-20 tube I decided to use it. Suggestions are always welcome. I love getting new ideas from others. I try not to reinvent the wheel but, sometimes men and men.
     
  9. Jul 13, 2018 #9

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    After several attempts with trying to find the center of the dowel, I got it. I did one wrap of masking tape around the pencil and then inserted it in the dowel. Then went to the belt sander and worked the wood down to the scale I needed. I did CWF and sand all of the fins and upper stage parts. The fins could have waited but the upper stage would have been pretty difficult after gluing. Thanks for watching. I'm enjoying myself.
     
    lakeroadster likes this.
  10. Jul 13, 2018 #10

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    I thought about drilling in the cone and having the pencil go straight through the upper stage to the tip. This would have increased stability a whole bunch. But, my tools are primitive and with drill pressing the nose cone, it was a one time shot. I have a feeling that I'm going to be re-gluing the upper stage to the nose cone frequently after flights. I WILL post a flight video for you. Thank you again.
     
    lakeroadster likes this.
  11. Jul 18, 2018 #11

    KarlS

    KarlS

    KarlS

    Well-Known Member

    Joined:
    Feb 7, 2011
    Messages:
    305
    Likes Received:
    0
    General Tools makes a "center finder". I got mine years ago for less than $10 It is brass. Really makes finding center easy and quick. I got mine at Sears, I think some of the big box stores might carry it.
     
  12. Jul 18, 2018 #12

    milehigh

    milehigh

    milehigh

    Well-Known Member

    Joined:
    Apr 26, 2016
    Messages:
    246
    Likes Received:
    10
    Looks like things are coming along nicely!
     
  13. Jul 18, 2018 #13

    Bruiser

    Bruiser

    Bruiser

    Well-Known Member

    Joined:
    Jun 7, 2018
    Messages:
    199
    Likes Received:
    16
    Looks good. Nice work you are doing here.

    -Bob George
     
  14. Jul 22, 2018 #14

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Still working on the upper stage. Seems to be coming along nicely. Cut a small dowel with a hobby knife for the detail. 1.jpg 2.jpg 1.jpg 2.jpg
     
  15. Aug 9, 2018 #15

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Finished with the Jupiter C. I will post a flight video. Thanks for the encouragement folks.
    20180809_175549.jpg 20180809_181753.jpg 20180809_181811.jpg
     
  16. Aug 9, 2018 #16

    kuririn

    kuririn

    kuririn

    Well-Known Member

    Joined:
    Oct 3, 2016
    Messages:
    801
    Likes Received:
    87
    Beautifully done. Are those Stickershock decals or home printed?
     
  17. Aug 10, 2018 #17

    Bat-mite

    Bat-mite

    Bat-mite

    Rocketeer in MD

    Joined:
    Dec 5, 2013
    Messages:
    8,166
    Likes Received:
    180
    Gender:
    Male
    Location:
    Maryland
    Sweet! You might consider kitting this and selling copies.
     
  18. Aug 11, 2018 #18

    JStarStar

    JStarStar

    JStarStar

    Well-Known Member

    Joined:
    Jun 6, 2009
    Messages:
    2,403
    Likes Received:
    8
    Very sharp looking!

    Great detail on the satellite tub!
     
  19. Aug 11, 2018 #19

    neil_w

    neil_w

    neil_w

    In search of a good winter project

    Joined:
    Jul 14, 2015
    Messages:
    4,456
    Likes Received:
    162
    Location:
    Northern NJ
    I had to go look up the Jupiter-C on Google Images to remind myself what the real thing looked like... and... well... it looks exactly like yours. :)

    Nicely done!
     
  20. Aug 11, 2018 #20

    CoachSteve

    CoachSteve

    CoachSteve

    Well-Known Member

    Joined:
    Feb 14, 2018
    Messages:
    163
    Likes Received:
    10
    Great detail, I love scratch builds, this one is top notch
     
  21. Oct 13, 2018 #21

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Finally got 3 flights in this afternoon.
     
    lakeroadster and kuririn like this.
  22. Oct 13, 2018 #22

    kuririn

    kuririn

    kuririn

    Well-Known Member

    Joined:
    Oct 3, 2016
    Messages:
    801
    Likes Received:
    87
    Nice straight flight, beautiful recovery just a few feet away. Looks like you did everything right, CL. You are right to be proud of this beauty.
     
    ToneDeafJunior likes this.
  23. Oct 13, 2018 #23

    lakeroadster

    lakeroadster

    lakeroadster

    Lone Wolf... No Club TRF Supporter

    Joined:
    Mar 3, 2018
    Messages:
    766
    Likes Received:
    71
    Gender:
    Male
    Location:
    Central Colorado
    Nicely Done! Congrat's...

    Awesome build thread too. Thanks for taking the time to document the adventure.
     
    ToneDeafJunior likes this.
  24. Oct 13, 2018 #24

    rharshberger

    rharshberger

    rharshberger

    Well-Known Member

    Joined:
    Oct 13, 2014
    Messages:
    7,090
    Likes Received:
    228
    Gender:
    Male
    Location:
    Pasco, WA
    Nice work and flight, not sure how I missed this build, but great job.
     
    ToneDeafJunior likes this.
  25. Oct 16, 2018 #25

    ToneDeafJunior

    ToneDeafJunior

    ToneDeafJunior

    Well-Known Member

    Joined:
    Oct 12, 2017
    Messages:
    85
    Likes Received:
    8
    Location:
    Folly Beach SC
    Just regular ole pin stripping black tape and letters from Hobby Lobby. I wish I could have found some in a skinnier font. And, thanks for the atta boy on the flight Kuririn.
     
  26. Oct 16, 2018 #26

    milehigh

    milehigh

    milehigh

    Well-Known Member

    Joined:
    Apr 26, 2016
    Messages:
    246
    Likes Received:
    10
    Wowzer!!!
    Nicely done model and excellent flight!! Love it when a model lands close to home.
     
  27. Oct 17, 2018 #27

    Bat-mite

    Bat-mite

    Bat-mite

    Rocketeer in MD

    Joined:
    Dec 5, 2013
    Messages:
    8,166
    Likes Received:
    180
    Gender:
    Male
    Location:
    Maryland
    Can't get to YouTube at work. Got to send myself a reminder to watch this at home!
     

Share This Page