Snap swivel styles for LPR/MPR?

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I use and recommend the sort that @neil_w pictured in post 21 above, in sizes from tiny for little 13mm-motored models (have never used a swivel in a MicroMaxx model) all the way up to some from the ocean fishing section of a sporting goods store rated at over 200 lbs. in the biggest ones I fly which are MPR/low HPR level 1 models.

Finding them is sometimes easy, sometimes not so. I think right now for LPRs I'm going through a package I got from Amazon.
 
I would only use those inexpensive swivels with clips from Walmart for LPR. I saw what appeared to be a fairly robust swivel/clip from Walmart fail (clip opened up) on a TARC qualifying flight and the altimeter reading on that flight was the best of their tree trials, but the flight was disqualified. Will never use a Walmart swivel for MPR. Most of those they sell are not even load rated. Big red flag! Only buy load rated swivels!

Additionally, I would appreciate some feedback on this one. I have always observed the recommended practice of attaching the shroud lines to a swivel and attaching that to the end of whatever shock cord is used. This makes the chutes easily moved to different rockets. But many times I have seen the shroud lines get so tangled with that arrangement that the flier discarded the whole chute. Instead, I attach the swivel to the end of the shock cord, then tie a loop in the middle of each shroud line (in this case, I am assuming a single double length of line is attached at each end to adjacent attachment points on the chute) and attach each loop to the snap. The chute can still easily be moved to a different rocket or a different chute can be attached to the rocket. If the shrouds get tangled it is easy to take them off the clip and straighten them out. Admittedly, it takes a little longer to change the chute with three or more loops to remove or attach. But if I am the only one I know of who uses this method, please help me understand what is wrong with it?
 
That's an interesting idea. I hadn't heard of that, but it might be worth a try. I do sometimes have a pretty tangled mess after a flight that tempts me to just pitch the whole thing out. But usually I manage to get things untangled .... eventually.
 
That's an interesting idea. I hadn't heard of that, but it might be worth a try. I do sometimes have a pretty tangled mess after a flight that tempts me to just pitch the whole thing out. But usually I manage to get things untangled .... eventually.
This is what I've been doing:

https://www.apogeerockets.com/education/downloads/Newsletter368.pdf
See page 4.

It's a variation on the "tie a loop in the shroud line" idea.

Hans.

Edit: I'll add that I've had no tangled lines after I started doing this. Or ones that were so trivially tangled that it only took seconds to undo,
 
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Additionally, I would appreciate some feedback on this one. I have always observed the recommended practice of attaching the shroud lines to a swivel and attaching that to the end of whatever shock cord is used. This makes the chutes easily moved to different rockets. But many times I have seen the shroud lines get so tangled with that arrangement that the flier discarded the whole chute. Instead, I attach the swivel to the end of the shock cord, then tie a loop in the middle of each shroud line (in this case, I am assuming a single double length of line is attached at each end to adjacent attachment points on the chute) and attach each loop to the snap. The chute can still easily be moved to a different rocket or a different chute can be attached to the rocket. If the shrouds get tangled it is easy to take them off the clip and straighten them out. Admittedly, it takes a little longer to change the chute with three or more loops to remove or attach. But if I am the only one I know of who uses this method, please help me understand what is wrong with it?
Can you post a picture to show what you're describing here? I'm curious as to if this method would work for me.
 
This is what I've been doing:

https://www.apogeerockets.com/education/downloads/Newsletter368.pdf
See page 4.

It's a variation on the "tie a loop in the shroud line" idea.

Hans.

Edit: I'll add that I've had no tangled lines after I started doing this. Or ones that were so trivially tangled that it only took seconds to undo,

I like the rotary punch (leatherworker) tool shown in Hans (Chris) Michielssen's article in the Apogee Peak of Flight newsletter. I wish there was such a rotary punch tool that had just slightly larger punches on it - up to 1/4 inch. The tools I have found on Amazon only go up to 4.5 mm, which is a bit smaller than 3/16".
 
I was in my local Walmart today and looked around in the fishing area. I found some snap swivels that looked like this. I doubt if they are they highest quality but I thought they would work for LPR parachutes and they are cheap so I bought a package.
View attachment 539123
Yes they work for LPR.. Walmart and sporting good stores is where i purchase mine. Search a tread on snap swivels....plenty of comments for MPR and HPR....including Kit swivels
 
That's an interesting idea. I hadn't heard of that, but it might be worth a try. I do sometimes have a pretty tangled mess after a flight that tempts me to just pitch the whole thing out. But usually I manage to get things untangled .... eventually.
I've been swapping long shock cords from one rocket to another but I've found that it helps to have an extra at a launch in case I get a tangle that I don't want to take the time to unravel at the field.
I've spent a lot of time doing experiments on my long shock cords to find a way that they will deploy without tangles. My spool has worked the best, but when I recover a rocket I usually grab it and head back to the car, that's when I tend to get the worst tangles.

I use and recommend the sort that @neil_w pictured in post 21 above, in sizes from tiny for little 13mm-motored models (have never used a swivel in a MicroMaxx model) all the way up to some from the ocean fishing section of a sporting goods store rated at over 200 lbs. in the biggest ones I fly which are MPR/low HPR level 1 models.

Finding them is sometimes easy, sometimes not so. I think right now for LPRs I'm going through a package I got from Amazon.
Amazon has so much stuff and their search facility is not very good. I've had better luck searching on ebay but it still takes some time.
 
Amazon has so much stuff and their search facility is not very good. I've had better luck searching on ebay but it still takes some time.
That's for sure. I must have searched for "coast lock" type swivels several times before I finally found what I was looking for. At least now I can search my own prior orders....
 
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