reefing kevlar shock cord

Discussion in 'Recovery' started by dwightr, Apr 14, 2019.

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  1. Apr 14, 2019 #1

    dwightr

    dwightr

    dwightr

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    I love Kevlar for it's strength but hate the lack of stretch.
    Has anyone tried reefing it with heat shrink tubing?
    I've been using about a 4" loop covered with heat shrink.
    I still reef the rest of the cord with masking tape but the one fold with heat shrink takes a lot more force to tear out. It usually doesn't tear out but it does give one last layer of protection in a violent deployment. IMG_2051.jpg
     
  2. Apr 14, 2019 #2

    G_T

    G_T

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    https://en.wikipedia.org/wiki/Chain_sinnet



    Just don't knot the end. Then when it is pulled it all unravels progressively. You do not need to braid this tight and IMHO you don't want to. It doesn't need to be tight for this application. A little loose is good.

    I've seen knot pictures and instructions that have this one wrong. The video shows how to do it. It is very fast and easy. It also seems to go under numerous names online.

    Gerald
     
  3. Apr 14, 2019 #3

    Bat-mite

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    If you're getting violent deployments, why not back off on your ejection charge?
     
  4. Apr 14, 2019 #4

    rharshberger

    rharshberger

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    You can do it that way but z-folding and masking tape work fine, my concern is that the reefing using shrink tube might snag or fail to work, the method showed in the picture in my post has not yet failed on many flights and on lighter rockets one or two bundles have even still been intact on landing, the other 3 bundles have provided enough shock absorbing resistance, z-fold and tape is also quick, cheap and won't leave non-biodegradable trash on the flying field.
     

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  5. Apr 14, 2019 #5

    Banzai88

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    In smaller rockets I've done the crochet method, seems to work rather well.
     

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