How many tape loops in their shock cords?

Discussion in 'The Watering Hole' started by John Taylor, Dec 2, 2019.

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  1. Dec 2, 2019 #1

    John Taylor

    John Taylor

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    Iv'e read about taping loops in shock cords to lessen the shock as it were, upon deployment. I'm thinking it might also keep the z-folded cord more organized in the tube. Does anyone do this? And if so any issues?
    I was considering using blue tape.
    Thanks
     
  2. Dec 2, 2019 #2

    Onebadhawk

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    I got tired of picking tape pieces off of my harnesses..
    The small rubber bands from childrens braces works perfectly and leaves no trace..

    Teddy
     
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  3. Dec 2, 2019 #3

    dr wogz

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    I think "it depends"

    I, personally, haven't.. yet. I see others do, but generally on the much larger birds, where there is a significant mass being 'ejected'.
     
  4. Dec 2, 2019 #4

    timbucktoo

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    I typically use 3, more or less.
     
  5. Dec 2, 2019 #5

    richP

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    Both tape and rubber bands. I do a few (2-3) taped z-folds towards the end of the cord to help in absorbing any over-energetic separation. The remainder of the z-folded shock cord gets small rubber bands to keep it organized and help in consistent unfolding.
     
  6. Dec 2, 2019 #6

    Zeus-cat

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    I fold over several inches of shock cord and wrap in masking tape. I do as many loops as will fit on the cord.
     
  7. Dec 2, 2019 #7

    Nytrunner

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    I tape my cords.

    I make ~4 loops of shock cord that are as wide as the tube diameter, and do a wrap of masking tape so that the loose ends pull the tape directly apart (as below).
    Typically I'll do as many of those bundles as the cord length allows

    upload_2019-12-2_12-1-43.png
     
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  8. Dec 2, 2019 #8

    Onebadhawk

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    Thank you..
    I didn't know how to draw it and post it..
    It is important to note,
    the placement of the band is important..
    Notice how the legs coming out from under a band bot come out from the same direction..
    This is most important..
    I also make that band further up, not in the center,
    though that isn't as important as both legs coming out of the band in the same direction..

    Teddy
     
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  9. Dec 2, 2019 #9

    Buzzard

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    I flew an Estes PSII Nike Smoke at a recent DARS launch. Since it was modified and had a large amount of Kevlar (plus an elastic bungie), I did Z fold the line and apply a couple of loose fitting bands of half-inch tape. I did it more for organizing the line, but was also hoping it would cushion the deployment. The Chute Release worked well at 300 feet.

    One of those techniques to try and then make adjustments as required.

    Chas
     
  10. Dec 2, 2019 #10

    John Taylor

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    Thank very much everyone. Great info. To me it's more for organizing the long cords. No matter how I fold it, the cord seems to become a mess in the tube. Thanks again.
     
  11. Dec 3, 2019 #11

    BEC

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    I have been known to use some 1/4 inch masking tape on very long Kevlar-only cords in some of my competition models, with the idea of organizing and also improving the chances that the entire length of the shock cord gets used (rather than just ejecting as a tangled mess). It’s worked for me most of the time. I do this especially when the model is heavier than a simple streamer or parachute duration model - B Cluster Altitude (so five spent B motors in the booster), payload altitude (an ounce of sand in the payload section) and E Altitude this past summer at NARAM-61 (half an ounce of lead plus a FireFly in the nose cone).

    I can see where a more rigorous approach to this would be very helpful for HPR models.
     
  12. Dec 3, 2019 #12

    llickteig1

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    The z-folding is great, as you suggest, to simply manage the straps. Keeps things tidy as you put the recovery gear into the tubes.

    I use masking tape as shown. It is very satisfying.
     
  13. Dec 3, 2019 #13

    Rob702Martinez

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    I z-fold several sections to aid in shock dampening and to organize and fit them down in the airframe. Using masking tape. I try to bundle 2 or 3 sections that will fit the diameter of the tube and then stack the next bundle on top and so on.
     
  14. Dec 3, 2019 #14

    jderimig

    jderimig

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    Try Velcro.
     
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  15. Dec 3, 2019 #15

    gary7

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    I would personally stay away from Velcro, it's too expensive for that use.
    The rubber bands I like to use are those you can buy at any drug store or Walmart etc that are used to hold hair into pony tails. Usually black in color, about the perfect size and very cheap.
     
  16. Dec 3, 2019 #16

    Steve Shannon

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    +1
    Pads of Velcro (both halves) stitched right to the shock cord so that they are reusable. The only thing I worried about was snagging the parachute material or the shock cord material so testing would need to be done.
     

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