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Teflon Dual pin & double closure loop

 


3fLiEr

Sep 11, 2001, 10:13 AM
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Teflon Dual pin & double closure loop Can't Post

I am posting this to gain others opinions (especially riggers) to the new closure method I have and many others are starting to get.

Instead of the curved pin through one closure loop I have two long teflon cables going through two closure loops. This I believe is a lot safer than the curve pin in the FreeFly environment.
Can anyone see/forecast/seen/heard of any problems that could / would occur with two closure loops through the one grommet.

Thanks for all input............

BSBD




skymedic  (C 33561)

Sep 11, 2001, 10:28 AM
Post #2 of 19 (918 views)
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Re: Teflon Dual pin & double closure loop [In reply to] Can't Post

I think this is the mod that Skreamer was asking about two weeks ago or so. do a quick search and see if you can find it.



Marc
Because I fly, I envy no man on earth


geoff

Sep 11, 2001, 2:27 PM
Post #3 of 19 (903 views)
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Several people in the UK have this mod - Andy Ford at Weston is a champion of it, and is doing this mod for other people.

You're not Fordy, are you.........are you?



3fLiEr

Sep 11, 2001, 11:58 PM
Post #4 of 19 (886 views)
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No I am not he ...............



DBTECH  (B 21186)

Sep 12, 2001, 8:14 AM
Post #5 of 19 (869 views)
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Re: Teflon Dual pin & double closure loop [In reply to] Can't Post

I have no problem with this as long as there is a small guide ring near the closing loop/grommet, as this will assure a cable pull on the same plane as the grommet. This will assure that the loop is not "pulled/lifted" during cable extraction. I would not depend on the cover flap for this function.
Also--why do you feel you need a duel loop and cable? Also, the use of 1000lb Spectra for a closing loop would have great strength and longevity when used with a Teflon coated cut-away cable.

Dave Brownell



alan  (D 17868)

Sep 12, 2001, 1:09 PM
Post #6 of 19 (848 views)
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Re: Teflon Dual pin & double closure loop [In reply to] Can't Post

In reply to:
I have no problem with this as long as there is a small guide ring near the closing loop/grommet, as this will assure a cable pull on the same plane as the grommet.
I'm not sure I agree with this. The guide ring is used on the reserve/RSL systems on many rigs, but those use a hard, straight pin, necessitating the pull on the same plane. The flexible teflon pin would/should act the same as the curved pins in common use and thereby not need to be pulled in the same plane as the grommet. Coated cable is used on Strong student rigs and on the Strong Tandem drogue release system very successfully without an added guide ring. Drawback to the teflon cable pin......make sure it is in good shape, with no cracks or nicks. Two loops means security if one breaks for whatever reason. Two cables means twice as many chances for one to have a nick,crack, or kink. Life is about decisions and compromises.

In reply to:
Also, the use of 1000lb Spectra for a closing loop would have great strength and longevity when used with a Teflon coated cut-away cable.
I wholeheartedly agree with this, as I have been using Spectra for my closing loops for several years now. I have used the 1000# and the microline weights with success. No stretch(loop stays tight), less friction during pin extraction(one reason why you want a tight loop), and way more durable. Way less resistant to friction heat so it is important to remove the pull-up chord slowly and from under the pin. I have seen the 1000# take a "set" when used on rigs with spring loaded pc's, keeping the flaps closed. Just takes a bump or nudge to open it, but it is still a Total Malfunction until you or your AFF/JM react.



alan


freeflynick  (D 24960)

Jun 16, 2003, 1:01 PM
Post #7 of 19 (741 views)
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Re: [3fLiEr] Teflon Dual pin & double closure loop [In reply to] Can't Post

I also use the 2 teflon pin system on my main, but with only one closing loop. I also do not use the mod for an in-plane pull as the teflon cable is flexible enough to handle this.
2 things to be carefull of - if the teflon coating cracks, etc. you may have the situation where the cable will pull out leaving the teflon coating holding your container closed. Also, there must be enough loose bridle above the pin (between the pin and the bag) to allow the extra length of the pin to be extracted. Too short a bridle will result in a pilot-chute in tow.
I am big on this sytem......the chances having your pin pushed/kncked out in the plane or by a hard freefall dock/collision is greatly reduced.
You do get some weird looks when you ask for a pin-check though!!


RMURRAY

Jun 17, 2003, 9:21 AM
Post #8 of 19 (697 views)
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Re: [3fLiEr] Teflon Dual pin & double closure loop [In reply to] Can't Post

I saw this posted a while back and sent it to a friend. I can't find the original now but here it is cut and pasted from my email. comments on the subject by Bill Booth...

First, the yellow coating I use on my breakaway handles is Lolon F (an "alloy" of nylon, not Teflon), coating a 7x7 steel cable. It is the best choice for breakaway cables for several reasons. It is very tough, reasonably slippery, flexible, easy to form ends with, and won't get brittle until -60C. I have never heard of it cracking or coming off the cable in the 20 years I have been using it. (Jump shack IS using Teflon, which they
color code red. We do not use it for too many reasons to go into here.)
The black coating we use for student ripcords is another form of nylon. We do not use it for 3 ring cable because it is too stiff, not as slippery, and cracks far easier than Lolon F. However, Its stiffness is a good feature for a spring loaded pilot chute main container system, and because main systems are packed before each jump, a crack should be easily spotted.

I offer a third kind of nylon, with no color coding, for main container flex pins on my older Tandem systems. It is a thicker coating on a thicker steel cable. Each coating and cable size is carefully chosen for its application after a lot of testing.

Here are the positives and negatives of flex pins on solo system main containers.

Positives:
1. If your container is too big for your canopy and/or your closing loop is too long, and you jump a rig without adequate bridle protection, and your entire bridle comes out of the pilot chute pouch (without the pilot chute) while doing head down, then the flex-pin is less likely to be prematurely removed by the wind drag on the horseshoed bridle, which by the way, is well under one pound..

Negatives:

1. Because the flex-pin is longer than a curved pin, you must be very careful to leave enough pilot chute bridle, between the pin and bag, slack AND exposed, to allow the pin to leave the loop. If you carefully tuck all bridle between the pin and the bag safely inside your container, you will have a pilot chute in tow malfunction.
2. Because the flex-pin is longer and has more surface friction than a stainless curved pin, it damages your closing loop ten times faster. Also, you cannot put your pull-up cord under a flex-pin before removing it as you would with a stainless curved pin, because the pull-up cord would then cut grooves in the nylon coating of the flex-pin causing a possible total on your next jump. This causes you to further damage your closing loop each time you remove your pull-up cord. And the heat damage the flex-pin and pull-up cord do to your closing loop is nearly invisible. This sets you up for a broken loop, out -of-sequence horseshoe malfunction. Do you pack your own rig every time? Are you sure the packers understand the above limitations of your flex-pin system?
Then you have to worry about which type of nylon coating your flex-pin has (will it crack, or splinter, or come off the steel cable core?), and whether the nicopress swage which holds the whole thing together was properly applied. Standards for the above items are simply not published.
3. Curved pins cannot be "pushed" out, they simply rotate in place. Try it. When a curved pin comes out prematurely, it was most likely pulled out by a bridle snag. And anything which snags your bridle will probably not stop pulling after only one inch. So flex-pins offer no protection from bridle snag induced premature openings.

This is just the short list. If flex-pins were better for most solo rig applications, we would offer them. We don't.

Bill Booth


RichM  (D 100226)

Jun 17, 2003, 1:07 PM
Post #9 of 19 (655 views)
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Re: [RMURRAY] Teflon Dual pin & double closure loop [In reply to] Can't Post

In reply to:
Positives:
1. If your container is too big for your canopy and/or your closing loop is too long, and you jump a rig without adequate bridle protection, and your entire bridle comes out of the pilot chute pouch (without the pilot chute) while doing head down, then the flex-pin is less likely to be prematurely removed by the wind drag on the horseshoed bridle, which by the way, is well under one pound..
Bill Booth

But if you pack your pc with your bridle exiting the pc bundle at the opposite end to the hackey and then coming up the side of the pc bundle (aka common freeflyer way) the full bridle out horsehoe mal is avoided anyway, unless I've missed something. Apparently leaving only cons and no pros according to Bills list.

Thanks for posting it RMurray.


Premier Remster  (C License)

Jun 17, 2003, 1:12 PM
Post #10 of 19 (651 views)
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Re: [RichM] Teflon Dual pin & double closure loop [In reply to] Can't Post

Quote:
if you pack your pc with your bridle exiting the pc bundle at the opposite end to the hackey and then coming up the side of the pc bundle

Maybe I'm not visualizing this right, but isnt this EXACTLY how to increase the odds of a horseshoe is you pull on the briddle... wont this pc packing method create a hard bunch and hard / impossible pull with a pulled briddle?


AlanRussell  (C 101105)

Jun 18, 2003, 5:48 AM
Post #11 of 19 (617 views)
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Re: [freeflynick] Teflon Dual pin & double closure loop [In reply to] Can't Post

Hello Nick

Good to hear from you.

To add to the general discussion, I have had a loop of lolon B (cutaway cable) fitted with a swage (making, effectively 2 pins) in place of the original curved metal pin on my Javelin for over 2 years and 500 jumps. This is also used on the static-line R.A.P.S. kits of my Club.

I agree that it provides more protection from the pin being knocked out in the plane or by hard docks/collisions in freefall and also reduces the chances of a horseshoe malfunction.

To answer some of the "cons", if you want to get one fitted, get it done by someone who is experienced in doing so. If you are in the U.K., this is certainly possible as I know that there are people at Weston, Langar and in Scotland at least who fit this profile.

I suspect that my loop is tighter than most people's and my container is the best size for the canopies that I have. I have not noticed a dramatic increase in closing loop wear (my current loop has around 100 jumps). I use 1 loop made of normal closing loop material, not 1000 lb Spectra and carefully remove the pull-up cord underneath the pins. There has only been one occasion when maintenance has been required on the pins (a rough bit at the end) but I admit that these pins do require more stringent checking than metal pins. However, I pack my own kit about 99 % of the time and am meticulous.

I believe that it is harder to push my pin out than a conventional, curved metal pin, as it bends as well as turns.

Also, the 2 pins are better than 1 because it makes it harder for the loop to pull the pin into the grommet.

Please do not use any type of "guide" with these pins, as it reduces the pin's ability to turn and flex, making it less safe (see above). Also, in the event that deployment was initiated when not flat and level, with the guide above the closing loop, the pin would have to bend more due to its restricted ability to turn , making a PC in tow more likely.

In conclusion, I believe that this system is better if you have it installed by someone who is skilled and experienced at doing so and who explains to you how to use it best and if you are prepared to check your main pin and closing loop for wear each jump.

Disclaimer: I have no financial interest in this system and have no rigging qualifications, I am just an experienced and conscientious user with some engineering knowledge.


RichM  (D 100226)

Jun 18, 2003, 11:52 AM
Post #12 of 19 (591 views)
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Re: [Remster] Teflon Dual pin & double closure loop [In reply to] Can't Post

In reply to:
Quote:
if you pack your pc with your bridle exiting the pc bundle at the opposite end to the hackey and then coming up the side of the pc bundle

Maybe I'm not visualizing this right, but isnt this EXACTLY how to increase the odds of a horseshoe is you pull on the briddle... wont this pc packing method create a hard bunch and hard / impossible pull with a pulled briddle?

Maybe it's my misunderstanding. I thought that if air catches under whatever exposed bridle there is, it can work out the remaining bridle within the pc bundle until there is enough out to create enough drag to pull the pin and consequently horseshoe. Packing the bridle around the back of the pc bundle prevents the stowed bridle from escaping. Am I missing something? Why would you pull the bridle and not the hackey on a BOC system?


Premier Remster  (C License)

Jun 18, 2003, 1:15 PM
Post #13 of 19 (572 views)
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Re: [RichM] Teflon Dual pin & double closure loop [In reply to] Can't Post

Its a case of what would you rather have:

with your option, IF you have a horeshoe for whatever reason (with the PC in its pouch), your PC will probably be pulled from the back on the pouch to the mouth of it, and may very easily bunch up in a way that will not make it possible to pull it free. This means you will have to pull reserve into a mess since even with a cutaway, you'll be dragging nylon. Not good.

with the other option, if you have a horseshoe (with the PC in its pouch), chances are the mal itslef will pull the PC, therefore you would not have a horseshoe, you'd have a premature opening. IF that mal doenst pull the PC, chances are the PC would not be bunched up, allowing you to pull it, then either stay with the main if it flies, or cutaway and pull reserve into clean air.


RichM  (D 100226)

Jun 18, 2003, 3:22 PM
Post #14 of 19 (562 views)
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Re: [Remster] Teflon Dual pin & double closure loop [In reply to] Can't Post

Agreed, although it seems with the pack I describe there is little chance of a horseshoe from loose bridle, although that still leaves pin knock outs. Having said all this I cant remember hearing of a horseshoe mal.


flipper  (D 11524)

Jun 18, 2003, 11:59 PM
Post #15 of 19 (544 views)
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Re: [freeflynick] Teflon Dual pin & double closure loop [In reply to] Can't Post

hey nick....

hows it going...?

Flipper


SkydiveMonkey  (B 102345)

Jun 19, 2003, 12:13 AM
Post #16 of 19 (538 views)
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Re: [RichM] Teflon Dual pin & double closure loop [In reply to] Can't Post

Pic of a horseshoe extracting the pc I found ...


(This post was edited by SkydiveMonkey on Jun 19, 2003, 12:13 AM)
Attachments: Mal 1 - Horse-shoe.jpg (20.9 KB)


Premier PhreeZone  (D License)
Moderator
Jun 19, 2003, 5:56 AM
Post #17 of 19 (519 views)
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Re: [SkydiveMonkey] Teflon Dual pin & double closure loop [In reply to] Can't Post

Thats not a horseshoe. That was a premature opening due to the PC getting kicked out. You can see the bag since the PC deflated and there was nothing to lift the bag with.


SkydiveMonkey  (B 102345)

Jun 19, 2003, 6:12 AM
Post #18 of 19 (517 views)
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Re: [PhreeZone] Teflon Dual pin & double closure loop [In reply to] Can't Post

That was a pic I was sent and was told it started as a horseshoe, and the pc got pulled out by drag on the bridle etc.


sunshine  (D License)

Jun 19, 2003, 8:02 AM
Post #19 of 19 (502 views)
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Re: [SkydiveMonkey] Teflon Dual pin & double closure loop [In reply to] Can't Post

Quote:
Thats not a horseshoe. That was a premature opening due to the PC getting kicked out. You can see the bag since the PC deflated and there was nothing to lift the bag with.

Quote:
That was a pic I was sent and was told it started as a horseshoe, and the pc got pulled out by drag on the bridle etc.

Phreezone is correct. I was on that jump. It was a 4way horny gorilla. The guy seen here had a premature deployment, not a horseshoe.


(This post was edited by sunshine on Jun 19, 2003, 9:14 AM)



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