Big Betty Anti-Zipper

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Well-Known Member
Oct 13, 2003
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Building yet another Big Betty and this one im going to mod to run "E" motors. I have other bettys i've modded to run "D" motors and none zippered but i could tell that it was very close to doing so.
Standard setup with Kevlar secured to mmt and plenty of eleastic shock cord attached.
1) So will that standard setup be ok with the extra forces of the "E" motors?
2) Should the kevlar extend past the end of the body tube or terminate just inside the body tube?

BTW, i always CA the edges of the BT for extra strength.
Gotta run, bbl
Thanks in advance for any and all help!



Well-Known Member
Jan 18, 2009
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A seldom-mentioned option that could apply here is the external anchor.

If you are using kevlar, it would be just as easy to anchor to a fin root and embed that part of the kevlar in the root fillets. Run the line up the outside of the tube and under the NC to get to the recovery system. This completely sidesteps any threat of zipper at the front of the BT, and leaves the inside of the BT free and clear of all obstructions, blockage, or snags that might interfere with recovery deployment.