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accooper

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OK, I guess I will share this with all of you. Have you ever gotten tired of your parachute shroud lines getting all tangled up? Me too! And since I make all my own shopping bag parachutes it really gets frustrating. In fact I couldn't hardly get one flight before the lines got tangled

Here is what I have come up with and it seems to work very nicely. Make a bridle(at least that is what I am calling it).

It is basicily a length of kevlar thread with snap swivels on the ends(see enclosed picture). One end connects to the nose cone and the other to the parachute. The shock cord connects to the nose cone as well. On the parachute use a barrel swivel. After 7 flights with two different rockets not a single tangle.

Andrew
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bridle.jpeg
 

gpoehlein

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Something else that will help keep shroud lines from tangling is simply how you rig them. Check out Micromeister's reply #5 in this thread:

http://www.rocketryforum.com/showthread.php?t=2407&highlight=shroud+lines

Ever since I've started rigging chutes this way, I've had a lot fewer tangled shroud lines. It really does work. I've mostly stopped using snap swivels on my chutes - I've actually had a couple fail (the wire on the snap part can deform and open if the ejection or deployment is hard enough).
 

MarkII

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After reading several posts in a thread on YORF about a year or so ago, I replaced all of my "safety pin"-style snap swivels with coastlock swivels. Even when this type is stressed beyond its test weight, the bail never releases - it just gets tighter. Here is the link to that thread, which contains a good deal of useful information:

http://www.oldrocketforum.com/showthread.php?t=4507

Attaching the parachute to a short extension, as in the item that Andrew shows, is probably a good idea in many situations. It allows the nose cone or payload section to dangle freely after deployment of the recovery system. When the parachute opens, it is the attachment of this line to the shock cord that takes the stress, rather than the attachment point at the base of the nose cone. This type of parachute attachment has been used in model rocketry for years, and it is the norm in HPR. Rather than installing a swivel at both ends, though, it is simpler and no doubt stronger to just tie a loop in the shock cord a few inches below the attachment to the nose cone, and then just attach the parachute there, using a strong snap swivel if desired. It accomplishes essentially the same thing. One can optionally attach a short line to that loop (I'd make it permanent, though) and then attach the parachute to that extension.

MarkII
 
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accooper

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That is how I attach my parachute lines. Have for years. Still doesn't keep them from getting them tangled. Helps but doesn't keep them tangle free.

Andrew
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Micromeister

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Part of the "tangle" is more then likely "built in" by the way the Shrould lines are attached. if your building the chutes pre the instructions in Estes kits your building in at least two twisted lines.

Snapswivels regardless of brand or make to a fine job of keeping your chutes for tangling further provided the model has enough weight to allow the swivel to rotate under canopy.

Another tangle reducing as well as parasheet oscillation dampening addition is a center spill hole.

Personally I like the slightly lighter snap swivels with the sure-lok but haven't really ever had a problem with the standard type brass swivels on LPR and MPR models up to size #2 swivels.
 

accooper

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I have been building my parachutes like in picture A for years. Building this way is no guarantee they they won't still get tangled.

Andrew
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Micromeister

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I have been building my parachutes like in picture A for years. Building this way is no guarantee they they won't still get tangled.

Andrew
Dark Lord Of The Scratch Builders

Tangles are sometimes more a product of the way the lines are packed then the way they are attached. twisting them around the folded canopy can cause shrouds to become tangled, it's better to neatly stack then on top of the canopy in the model body.

the type of line used for the shrouds can also play a very big part in twisted or more accurately Fowled shroud lines. Cotton and other fibrous threads make pretty nasty shrouds for just that reason. I've switched to 13lb kevlar as my main shroud material for lpr, sport and even mid power models with chutes up to 30". larger or rip-stop nylon get a little heavier kevlar shroudlines. Braided is better but harder to find and more expensive, Twisted kevlar is cheaper, a good bit stiffer but still doesn't Tangle or fowl nearly as often as other line types.
Hope this helps.
 
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