Snap Swivels, and LPR parachute attachment

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neil_w

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Following assorted questions apply to parachutes up to 24", for LPR and small MPR, because that's what I fly.

I use coast-lock snap swivels to attach my parachute to my shock cord. I've seen coast-lock swivels specifically recommended many times here, so I use them, although I find the small ones to be devilish to snap and unsnap. Is there a trick? Also, are there any known-good brands? I need to order some more, and as usual am bewildered by the array available on Amazon, most with very high aggregate ratings but also with many highly rated reviews saying that they're garbage (a common problem trying to decipher Amazon reviews).

Next: I was watching @Flyfalcons 's excellent video on the Bullet Bobby kit and when he attached the parachute it just about blew my mind:
His method was:
  1. Attach the snap swivel ring to the shock cord
  2. Tied a loop at the end of the shroud lines
  3. Hooked the snap to the parachute shroud lines.
1618758723139.png

The reason this blew my mind is because it is exactly opposite to what I've always done, which is:
  1. Attach the parachute to ring in the swivel, using a cow hitch. I admit I find this to be troublesome, especially with the heavier shroud lines on nylon chutes, but it only has to be done once per parachute.
  2. Tie a loop into the shock cord (elastic, in my case; Ryan's was Kevlar)
  3. Attach the snap to the shock cord loop
OJtpEj0nSRaJuTsOXuvuXQ_thumb_12242.jpg

Both methods allow for easy removal/swapping of parachutes. Ryan's method permanently attaches the swivel to the shock cord, which seems troublesome to me.

What is standard and/or best practice here?
 

mjennings

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The brand I usually get has an eagle on the package. Can't think of the name at the moment. For LPR I don't worry about the weight rating. I just cut the elastic at an angle and pull the swivel through. It is usually a pretty tight fit. You could use an alpine butterfly knot in the elastic if you want to lock it in place. If you are having issues getting them open/closed I've found the bigger ones to be easier. They are pretty negligible weight wise.
 

neil_w

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So you're hooking the shock cord to the small loop, aka Ryan's method (minus the tied shroud lines)?
 

mjennings

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Yes, but because of how tight the swivel is on the elastic I don't tie it off.
 

Flyfalcons

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Tying a Kevlar cord through the swivel loop is pretty easy but a different method may be more appropriate when dealing with a wider and relatively weaker elastic or rubber shock cord.
 

BABAR

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Following assorted questions apply to parachutes up to 24", for LPR and small MPR, because that's what I fly.

I use coast-lock snap swivels to attach my parachute to my shock cord. I've seen coast-lock swivels specifically recommended many times here, so I use them, although I find the small ones to be devilish to snap and unsnap. Is there a trick? Also, are there any known-good brands? I need to order some more, and as usual am bewildered by the array available on Amazon, most with very high aggregate ratings but also with many highly rated reviews saying that they're garbage (a common problem trying to decipher Amazon reviews).

Next: I was watching @Flyfalcons 's excellent video on the Bullet Bobby kit and when he attached the parachute it just about blew my mind:
His method was:
  1. Attach the snap swivel ring to the shock cord
  2. Tied a loop at the end of the shroud lines
  3. Hooked the snap to the parachute shroud lines.
View attachment 460361
The reason this blew my mind is because it is exactly opposite to what I've always done, which is:
  1. Attach the parachute to ring in the swivel, using a cow hitch. I admit I find this to be troublesome, especially with the heavier shroud lines on nylon chutes, but it only has to be done once per parachute.
  2. Tie a loop into the shock cord (elastic, in my case; Ryan's was Kevlar)
  3. Attach the snap to the shock cord loop
View attachment 460360
Both methods allow for easy removal/swapping of parachutes. Ryan's method permanently attaches the swivel to the shock cord, which seems troublesome to me.

What is standard and/or best practice here?
I am with you, I attach the chute to the ring, the snap to the cord, so the swivel stays with chute.

a trick to get the shroud lines through the ring

pass a single line of thread through the ring.

pass the line through the three (or four, I make octagon chutes) shroud loops.

pass the line back through the ring going the opposite way. Now the two ends of the thread are on one side of the ring, the loop through the shroud lines on the other.

pull on the two ends to pull the loop WITH the shroud lines through the ring.

pull enough of the shroud loops through the ring that you can thread the chute through the combined three or four loops.

Bob’s your Uncle!

the Eagle Claw swivels from Wally World have all worked fine for me.
When I went to Mid Power with my interceptor E I had an X chute that REQUIRES a swivel, I bought one from @Onebadhawk , I think it ran me about $9 with shipping. It was worth it, it worked perfectly with the spinning chute.
 

jrap330

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Following assorted questions apply to parachutes up to 24", for LPR and small MPR, because that's what I fly.

I use coast-lock snap swivels to attach my parachute to my shock cord. I've seen coast-lock swivels specifically recommended many times here, so I use them, although I find the small ones to be devilish to snap and unsnap. Is there a trick? Also, are there any known-good brands? I need to order some more, and as usual am bewildered by the array available on Amazon, most with very high aggregate ratings but also with many highly rated reviews saying that they're garbage (a common problem trying to decipher Amazon reviews).

Next: I was watching @Flyfalcons 's excellent video on the Bullet Bobby kit and when he attached the parachute it just about blew my mind:
His method was:
  1. Attach the snap swivel ring to the shock cord
  2. Tied a loop at the end of the shroud lines
  3. Hooked the snap to the parachute shroud lines.
View attachment 460361
The reason this blew my mind is because it is exactly opposite to what I've always done, which is:
  1. Attach the parachute to ring in the swivel, using a cow hitch. I admit I find this to be troublesome, especially with the heavier shroud lines on nylon chutes, but it only has to be done once per parachute.
  2. Tie a loop into the shock cord (elastic, in my case; Ryan's was Kevlar)
  3. Attach the snap to the shock cord loop
View attachment 460360
Both methods allow for easy removal/swapping of parachutes. Ryan's method permanently attaches the swivel to the shock cord, which seems troublesome to me.

What is standard and/or best practice here?
I think it is because the cone's eyelet might be tough to attached a swivel to and also the swivel will not get in the way of storing the chute in nose cone.
 

neil_w

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I think it is because the cone's eyelet might be tough to attached a swivel to and also the swivel will not get in the way of storing the chute in nose cone.
I'm not talking about connecting the swivel directly to the nose cone. Rather, whether the swivel is attached to the parachute and snapped to the shock cord (my normal method), or attached to the shock cord and then snapped to the parachute shroud lines (Ryan's and apparently others' method).
 

jrap330

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I'm not talking about connecting the swivel directly to the nose cone. Rather, whether the swivel is attached to the parachute and snapped to the shock cord (my normal method), or attached to the shock cord and then snapped to the parachute shroud lines (Ryan's and apparently others' method).
I know Neil-..What I am trying to say-1- that is why he attached it to shock and 2- he decided to try it backwards..to the ring permanently......no advantage excerpt you have now lost a swivel...or it could be directions in the kit. As for swivels...some of the members have suggested "kite" swivels but I thinks that is MPR to HPR. But as you stated....very interesting...
 

icyclops

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Following assorted questions apply to parachutes up to 24", for LPR and small MPR, because that's what I fly.

I use coast-lock snap swivels to attach my parachute to my shock cord. I've seen coast-lock swivels specifically recommended many times here, so I use them, although I find the small ones to be devilish to snap and unsnap. Is there a trick? Also, are there any known-good brands? I need to order some more, and as usual am bewildered by the array available on Amazon, most with very high aggregate ratings but also with many highly rated reviews saying that they're garbage (a common problem trying to decipher Amazon reviews).

Next: I was watching @Flyfalcons 's excellent video on the Bullet Bobby kit and when he attached the parachute it just about blew my mind:
His method was:
  1. Attach the snap swivel ring to the shock cord
  2. Tied a loop at the end of the shroud lines
  3. Hooked the snap to the parachute shroud lines.
View attachment 460361
The reason this blew my mind is because it is exactly opposite to what I've always done, which is:
  1. Attach the parachute to ring in the swivel, using a cow hitch. I admit I find this to be troublesome, especially with the heavier shroud lines on nylon chutes, but it only has to be done once per parachute.
  2. Tie a loop into the shock cord (elastic, in my case; Ryan's was Kevlar)
  3. Attach the snap to the shock cord loop
View attachment 460360
Both methods allow for easy removal/swapping of parachutes. Ryan's method permanently attaches the swivel to the shock cord, which seems troublesome to me.

What is standard and/or best practice here?
I just use regular fishing snap swivels...never had any problem. I attach the chute to the swivel and then attach the snap end to the nose cone. I do not like attaching metal swivels to elastic shock cords as there is a chance the force can cut into the elastic. Been doing this since 1982 and never lost a chute or nosecone...ever. Rockets don’t spin as much as the elastic shock cord doesn’t twist as much not attached directly to swivel or chute.
 

mbeels

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The reason this blew my mind is because it is exactly opposite to what I've always done, which is:
Heh, interesting. I've done it the same as you.

I bought packs of swivels off of E*ay in various sizes, and use the size that is just big enough to allow the parachute shroud lines to pass through the small eyelet (cow hitch, as you do). I got some of these for LPR:

1618874741274.png


And one of these sizes for MPR:

1618874768606.png


(HPR gets bigger stuff)

I wish I could tell you which sizes worked well for which rockets, but I now have such a mish-mash of shroud lines and swivels, I have no recollection of what I bought. But I do like to loop the parachute shroud lines around the small loop.
 

ep29030

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Have done it both ways over time, but generally do the cow hitch on the parachute and keep the swivel with the parachute. Have used about every brand out there--Eagle Claw works fine. Have been using the stainless barrel swivels, ordered from a kite supplier. Tackler suppliers are also good sources for quality swivels. I don't think quality is important until you get into MPR with higher loads. Seems about anything works on smaller rockets.
 

neil_w

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Does coast lock vs. regular (not sure what regular is called) matter? I saw coast lock recommended a number of times but I'm not entirely sure why.

I note that Eagle Claw doesn't seem to sell coast lock right now, at least on amazon.
 

mbeels

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I've seen coast-lock swivels specifically recommended many times here, so I use them, although I find the small ones to be devilish to snap and unsnap. Is there a trick?
Does coast lock vs. regular (not sure what regular is called) matter?
Yeah, for the smallest sizes I get the non-coastlock swivel versions (not sure what they're called either). I think at LPR I can't imagine either style has any significant advantage. I'd rather get the one that is easier to clip and unclip. But they still aren't easy, I sometimes resort to needle nose pliers.

I do like to put a single wrap of masking tape over the clip part, just to make sure that the exposed hooks or wire doesn't snag shroud lines. I think it just helps everything deply without getting tangled.
 

ep29030

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To me, the two big advantages of snap swivels: (1) allows parachute to be easily moved between rockets; (2) allows parachutes to rotate without tanging elastic/nylon bridle between rocket and nosecone. Flat round parachutes like to rotate, esp. when the vent hole is not used, or is too small.
 

shockie

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Heh, interesting. I've done it the same as you.

I bought packs of swivels off of E*ay in various sizes, and use the size that is just big enough to allow the parachute shroud lines to pass through the small eyelet (cow hitch, as you do). I got some of these for LPR:

View attachment 460604

And one of these sizes for MPR:

View attachment 460605

(HPR gets bigger stuff)

I wish I could tell you which sizes worked well for which rockets, but I now have such a mish-mash of shroud lines and swivels, I have no recollection of what I bought. But I do like to loop the parachute shroud lines around the small loop.
[/QUOTE]
I think the 1st pics are called safety snaps. There is an interlock type and then coastlocks.. All 3 can either be barrel or ball bearing.

 
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BEC

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Does coast lock vs. regular (not sure what regular is called) matter? I saw coast lock recommended a number of times but I'm not entirely sure why.
Because a sharp enough jolt (early or late sudden ‘chute opening) can pull the “regular” ones open. Yes, I have seen this happen.

A similar pull on a coast lock type might deform it but it’s much less likely to open.

Even though I fly with Ryan sometimes, I’d never noticed him using swivels that way. Interesting....
 

mbeels

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Because a sharp enough jolt (early or late sudden ‘chute opening) can pull the “regular” ones open. Yes, I have seen this happen.
What about the regular ones with "interlock"? It looks like it ought to to help prevent it getting pulled open.
 

BEC

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Those will also work. I find them harder to deal with (needle-nosed pliers are almost a requirement—even more so than with coastlock types) but they do work and sometimes are easier to find.

Basically any type that involves a hook or latch rather than a free end that can just be pulled out with a load is more secure than "regular" snap swivels.
 

neil_w

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I'm starting to get very confused about the different varieties

1) Coast lock
1619112593239.png


2) Interlock (what I think of as the "normal" kind):
1619112682969.png

3) ???

Is there a third kind being discussed here? Bernard, which type were you referring to here:
Because a sharp enough jolt (early or late sudden ‘chute opening) can pull the “regular” ones open. Yes, I have seen this happen.
 

rklapp

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I've only had one swivel open on me. The swivel was too small for the BT-80 Fat Boy with a streamer.


I like the Coast lock swivels but hesitant about the Interlock because I'm afraid the cords will catch on the wires sticking out. I find the problem with ordering swivels on Ebay is that one manufacturer's measurement for a #4 can be different than another's #4. I've bought many Eagle Claws from Walmart because they're like 50c each.

I've stopped attaching swivels to NC, doesn't seem like it's worth it. I attach the swivel and shock cord to the Kevlar cord in the BT because the swivel helps keep the tube from twisting with the cam. You can hear the swivel working with the Protostar. Not perfect, but helps...

 

neil_w

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Non-interlocking version of the basic kind, I'm not sure what the proper names are ("regular"?). These I think can pull open fairly easily:

View attachment 461025
Ah, now I see what the interlock is, and why you want it.

So I guess either the interlock or coast-lock snaps would work fine. The coast-locks don't have the protruding pins that would benefit from the tape wrap.

I guess I'll stick with coast-lock for now.
 

hobie1dog

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great thread. I'll likely use the Stainless Steel models I have in my fishing tackle box with the ball bearings.
 

BEC

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I'm starting to get very confused about the different varieties

3) ???

Is there a third kind being discussed here? Bernard, which type were you referring to here:
I see mbeels beat me to it.
9E14F6D0-E355-43CB-9B9F-19AB97F40A77.jpeg


Top two are swivels currently being supplied in ASP Neon Sport ’Chute kits (apologies to Andy Jackson) and below are coast lock swivels I recently got from Amazon and are starting to use since my supply of coast locks around this size was getting really low.

I will say that the force it took to open the second swivel tells me that the ones Andy is supplying in is ’chute kit are likely strong enough for anywhere a 12-18 inch plastic ‘chute might be used. But they are quite large for putting in a model for which a 12 inch LPR ‘chute is appropriate.
 
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