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autoset

Using a flexible cable to close the container instead of a pin

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I would like to hear your thoughts on this, i like the idea and it looks safer to me, no more worries about finding the perfect pressure point in the closing loop when you use a curved pin. It also "appears" impossible to get a "nothing out" mal because it looks like the cable would just slide out of the loop even with the little pull-force of a not-fully-inflated PC (PC in tow).

Also you would have to change the closing loop every now and then because it wears out fast from the friction with the cable.

Anyway these are just assumptions from a beginner so i may be wrong.>:(

Example Picture attached.

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Such a system already exists, it's called a flexpin. All our tandem rigs have it, and of course the S/L rigs.

A total mal is still possible: if too much tension is applied the cable gets kinked into the grommet and may lock.

ciel bleu,
Saskia

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The Flex pin can also get nicked then it will hook on the loop and have a PC in tow. There were 2 fatalities last year on ripcord rigs where the flex cable got nicked and they never were able to deploy a main canopy cand deployed the reserve too late.

The flex pin seems to be a very Europe thing to do, I've never seen them in use on sport gear here in the US.
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And tomorrow is a mystery

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I would like to hear your thoughts on this..



I see you found my study. I continue to jump that rig with the flexible cable closing pin with much success. http://www.pcprg.com/flexcab.htm

To answer some of the concerns:

1. It has to be built correctly as described in the study.

2. Yes, you need to continue checking the condition of the cable to be sure it doesn't get too big of a nick in it. Mine is the original cable with a lot of jumps on it. No nicks, and I don't do anything special.

3. The most likely reason for using a flexible cable is that your original pin is so loose it scares you, so you use the longer flexible cable. If the closing forces are high you probably won't use the flexible cable, and I wouldn't recommend it.

4. Of course you need to change the closing loop more often, but getting a sturdy material for the closing loop helps a lot.

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Using a flexible cable to close the container instead of a pin



It is funny (peculiar) that i asked the same question in my first week of skydiving.

Make sure your gear is all compatible (main, reserve and container), if it is then there should be sufficient tension on the closing loop to make a closing pin work as it was intended. If the closing pin is loose (at all), then only jump the gear if there is a flexipin but avoid jumping it at all. it is not safe to have a premature deployment.
"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

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...."If the closing pin is loose (at all), then only jump the gear if there is a flexipin ...."

I saw a couple of posts along these lines. I must be missing something.

What ever happened to that old "rocket-science" idea of adjusting the length of the closing loop properly?
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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in germany we use flex pins on tandem rigs...
but you have to put 2 cables throu the loop..
it works very safe, you can to a pincheck easyly on you own, as a tandempilot...
but its important to use 2 cabels to reduce the tension...one is to weak to take the pressure of the loop....

on tandems it make sense...on sport rigs you should use the right loop...:P

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What ever happened to that old "rocket-science" idea of adjusting the length of the closing loop properly?



Yeah, next someone will come along with this new "great idea" of instead of using gutted 550 addjusted to the proper lenght for a main closing loop, use bungie instead and just put a bite of your pilot chute bridle through it to close your main container!!! No pin needed!! :S


Flex pins have come and gone before... yes, they're still used on some systems, but were pretty much abandonded on sport rigs when Hank came up with the curved pin. If it ain't broke...

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iirc yellow is lolon (not teflon). They're 'often' seen with two cables instead of just the one (next to each other).

Seems like a way to (probably) be equally safe yet be able to differentiate onself from the other 99% of people and have a clever sounding reason to back it up too. A bit like pinpull. :P


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Ex-University of Bristol Skydiving Club
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Without commenting on the use of the flexpin itself I see a couple of potential problems on your setup.
Closing the right flap over the left can cause a container lock on some rigs if the bridle slides under the right flap. Even if you can't easily duplicate this mal on the ground you'll find it can't happen if you close flaps left over right. Please consult a rigger on this.
Second problem is the length of the flexpin, this length means that that much bridle must pull out from under your flaps before the closing loop is free. That's a lot of bridle to keep slack as opposed to only an inch or so for a curved metal pin.
Whatever system you choose understand it's proper use and maintenance.
Sometimes you eat the bear..............

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iirc yellow is lolon (not teflon). They're 'often' seen with two cables instead of just the one (next to each other).

Seems like a way to (probably) be equally safe yet be able to differentiate onself from the other 99% of people and have a clever sounding reason to back it up too. A bit like pinpull. :P



Ah, one of the doubters of the saftey of a Pull Out.

One day young Padi-Wan, one day.....:D
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You're not as good as you think you are. Seriously.

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Second problem is the length of the flexpin


Damm right!

I don't know how much bridle would come out on the rig pictured. I do know that with that length of pin it would be a definate mal on my rig.

Tandems and static line flex pins operate under different conditions to a sport rig. On static line the whole weight of the jumper is pulling the pin out. On a tandem, the drogue is somewhat bigger than a sport pilot chute.
Dave

Fallschirmsport Marl

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Without commenting on the use of the flexpin itself I see a couple of potential problems on your setup.



This is not "autoset's" setup.

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Closing the right flap over the left can cause a container lock on some rigs if the bridle slides under the right flap. Even if you can't easily duplicate this mal on the ground you'll find it can't happen if you close flaps left over right. Please consult a rigger on this.



By all means, send a picture of the situation you describe, because from the text I can't tell at all what you mean.

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Second problem is the length of the flexpin, this length means that that much bridle must pull out from under your flaps before the closing loop is free.



Covered in my reply and in the study.

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What ever happened to that old "rocket-science" idea of adjusting the length of the closing loop properly?



If a rig has a closing loop that originates on a tab between the reserve and main, of course. But many rigs now have loops that originate on the first flap to close. This unfortunately does not allow for much adjustment if a smaller canopy is installed in a rig made for a larger one.

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I ran into this problem with gear that I recently got. It is a Flexon and because the loop is attached to the top flap making it shorter is tough. I now have it where the length of the loop is almost even with the thickness of the stacked grommets. The container is more secure than it was, but I am still more mindful of redundant pin checks than most.
Sky Canyon Wingsuiters

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The original poster's photo shows yellow, nylon-coated cable, which is not my first choice for flex-pins.

There are at least five types of steel cable used to close skydiving rigs.

In the beginning, the first 3-Ring release cables had a clear coating. A few people also tried using this clear-coated cable for main ripcords, but the clear plastic sometimes cracked, creating hard pulls.

Then 3-Ring Inc. switched to cables with a yellow nylon coating.

Black-coated cable is commonly used for main ripcords on AFF containers, and is my first choice for closing sport rigs. This black coating is considerably stiffer, reducing the chance of cables sucking down through grommets.

Strong Enterprises encountered a similar suck-through problem with tandem main risers. Strong developed two solutions. The first solution involved making cutaway cables from bare steel cable, the same external diameter as yellow-coated cable. However, bare steel cables require an exotic form of welding to smooth the ends. Unfortunately, only Strong Enterprises have those exotic welding tools.
To reduce that production bottle-neck, Strong Enterprises switched to thicker, clear-coated cables for their tandems. Strong also uses flex-pins - made of clear-coated cable - to close their tandem main containers.

Jump Shack makes cutaway cables with red Teflon coating.

In conclusion, there are a lot of different colored coatings, but I only trust the black cable for closing main containers.

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In conclusion, there are a lot of different colored coatings, but I only trust the black cable for closing main containers.



Yep, if the container is tight, the black cable would be my choice too. My Centaurus that has the flex cable was too loose for comfort, that is why I use a cable.

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Closing the right flap over the left can cause a container lock on some rigs if the bridle slides under the right flap. Even if you can't easily duplicate this mal on the ground you'll find it can't happen if you close flaps left over right. Please consult a rigger on this.



By all means, send a picture of the situation you describe, because from the text I can't tell at all what you mean.



Here's one I prepared earlier.

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OK, I see how that can happen, but I was thinking that Martini was taking about it happening related to the flexible pin. What you drew could happen with any pin as far as I can tell. Perhaps we need another thread, "main container flap closing order", (and why).

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The potential mal I described and Erno pictured is definitely not a flexpin-related problem, that's why I declined comment on the flexpin. It may not even be common to all rigs, I was shown the bridle problem on a Javelin. I'm not a rigger and don't claim to know shit. It seems to me that closing left over right eliminates the potential hazard without introducing any new problems (assuming a right-hand boc) but, once again, I always tell people to consult a rigger if closing left over right isn't the manufacturer's reccommendation. You're right Gary, the flap order should be another thread as this should remain a flexpin thread. On that note I'll say that I find flexpins to have more flaws in general than curved pins as a container opening mechanism.
Sometimes you eat the bear..............

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