Bertha's breech baby ...

Discussion in 'Low Power Rocketry (LPR)' started by beantownJPL, Aug 29, 2019.

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  1. Sep 8, 2019 #31

    BABAR

    BABAR

    BABAR

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    Let’s hope for the best!
    Make sure you have a designated spotter for the booster, whether it tumbles or not, can be a challenge to find as it comes down quick , isn’t very big, and has no streamer or chute to flutter in the breeze!
     
  2. Sep 8, 2019 #32

    nosecone

    nosecone

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    Hello,
    Unfortunately, my Baby Bertha came in the mail yesterday and the body tube was completely crushed almost flat on one end with major creases. Looks like I will have to wait :(
    N.C.
     
  3. Sep 8, 2019 #33

    ebruce1361

    ebruce1361

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    The man with the plan. And some duct tape.

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    The booster on my gap staged BB has a streamer pulled out at ejection.
     
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  4. Sep 8, 2019 #34

    beantownJPL

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    What a bummer. Can it be saved considering the nose cone will be glued on? Or is it just created too badly?

    Contact Estes, they'll send you a new BT. They'll just want a photo.
     
  5. Sep 8, 2019 #35

    BABAR

    BABAR

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    Like to see details
     
  6. Sep 8, 2019 #36

    beantownJPL

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    Here she is in paint. I had tried to go for some stripes above the fins, but the red paint wrinkled there when I shot the clear coat. Fortunately no problem with the red of the fins. I sanded out the wrinkles and just shot another coat of the black metallic, and then another coat of clear over it. That's the second time I've had a problem with that Krylon Fusion red wrinkling on me ... I'll keep that in mind!

    [​IMG]
     
    Last edited: Sep 9, 2019
  7. Sep 8, 2019 #37

    neil_w

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    Nice paint! Is that Rusto black metallic, or Krylon?

    As an aside, *every* *single* *time* I see the title of this thread I think of this:
     
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  8. Sep 9, 2019 #38

    beantownJPL

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    Thanks! The paint is Rustoleum.

    That video made me LOL.
     
  9. Sep 9, 2019 #39

    beantownJPL

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    Speaking of video, here's the maiden on a B6-4.

     
  10. Sep 9, 2019 #40

    nosecone

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    Awesome. How did the ejected parts handle it ?
     
  11. Sep 9, 2019 #41

    beantownJPL

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    No damage. Flew it again on a C6-5, but didn't get a video. (Actually I did, but the framing was off, so I deleted it).
     
  12. Sep 9, 2019 #42

    ebruce1361

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    The sustainer pulls out a foot of kevlar that is taped to the inside of the body just below the motor mount. After that is the streamer followed by about another foot of kevlar. There is an additional nylon string that runs down the outside of the booster and is looped around the motor mount so the booster will descend horizontally under the streamer.
     

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  13. Sep 18, 2019 #43

    beantownJPL

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    Flew the Breech Bertha again twice this weekend on C6-5. It flies very nicely, and the rear ejection is working flawlessly.

    The first launch singed the chute a little, but it still mostly deployed. I noticed the motor tube had eroded a bit where the upper part of the motor hook goes through it. I patched the hole with a couple wraps of blue tape, and the second flight was perfect.

    I'm going to permanently patch that hole with some epoxy.
     
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