Help with a styrofoam cup build

Discussion in 'Oddrocs' started by CKaul04, Oct 30, 2018.

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  1. Oct 30, 2018 #1

    CKaul04

    CKaul04

    CKaul04

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    I was looking into the Flis Decafinator, but they went out-of-business before I could order one. Many small styrofoam cup at my disposal. Every website is sold out of the big foam rockets.

    Colin
     
  2. Nov 1, 2018 #2

    sooner.boomer

    sooner.boomer

    sooner.boomer

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    How tall of one do you want to make? Balsa Machining Service has body tube sections in 18" and 34" lengths. Pick the appropriate diameter,mMake a jig to center the hole on the bottom of the cup, then start cutting, stacking and gluing.
     
  3. Nov 1, 2018 #3

    CKaul04

    CKaul04

    CKaul04

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    Thanks, will try soon

    Colin
     
  4. Nov 2, 2018 #4

    Gus

    Gus

    Gus

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    Decaffeinator and Espresso were both rear ejection models. For the Espresso the main tube was BT50, just long enough to hold the BT5 motor mount, a streamer, and a shock cord attached to a front bulk-plate or plug. The tube went up through the first three cups, then the rest of the cups were just hot-melt-glued to each other, as high as you would like. Fantastic design.

    13 years ago my daughter built 5 Espressos for a Science Day demo launch at her school. Attached are photos of her build which should give you an idea of how they go together.

    I also never miss an opportunity to thank Jim Flis for this design which taught my daughter and I about rear ejection rockets. It was the first time we'd ever done it. We've used the technique lots and lots very successfully ever since. :) Last two photos are of the same kid and her somewhat more sophisticated two stage double rear-ejection model at this last summer's World Spacemodeling Championships in Poland. Her team, with a couple of slightly older teammates, finished third in the world!

    DSCN0551.jpg DSCN0552.jpg DSCN0560.jpg DSCN0559.jpg DSCN0558.jpg DSCN0562.jpg IMG_4842.jpg IMG_4900.jpg
     
    Last edited: Nov 2, 2018

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