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kingbunky

finger trapping toggle lines?

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i've seen references made to finger trapping your steering lines once you know they are the right length. what i'd like to know is, can the no-sew finger trap be used in this application? i'd like to do it to my rig because i have an older sabre 190 with the dual steering lines, and the two knots on the toggle, along with the excess brake line, make a rather ugly looking mess of lines when stowed.

(i was going to link to sid's page where i found the instructions in the first place, but it appears to be gone now!)
"Hang on a sec, the young'uns are throwin' beer cans at a golf cart."
MB4252 TDS699
killing threads since 2001

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I don't think the no-sew fingertrap (Jump Shack method) can be used because the there is only one free end.

You can fingertrap it and bartack it. It takes 5 min.

Alternatively, you can leave the knot and fingertrap the excess line like it's done on most reserves. The end result it's not too bad.
Memento Audere Semper

903

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cool... i was wondering mainly because the no-sew method is something i could probably do myself. we don't have a local rigger, and i don't really want to travel 100 miles to have it done. yes, the knots are ugly, and two of them are twice as ugly.

thanks for the info.B|
"Hang on a sec, the young'uns are throwin' beer cans at a golf cart."
MB4252 TDS699
killing threads since 2001

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I have looked at these instruction several times, and maybe I am just missing something.

Does this method require both ends of the line to be free?

If so, isn't this a problem on the end of an existing steering line?

I found a method that does not need both ends free and is significantly simpler, but no less secure.

I cannot take credit for this method. I found it on a canopy I was working on and reverse engineered the making of the loop.

I'll post something if people are interested.

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Hi Paul,,
I looked at those instructions on the JumpShack site for a long, long time and could not understand how they were supposed to work. Then someone sent me an email with some photos and all was well.

If you have a loop on the end, such as with a steering line, then you have to pull the loop back through the line to lock it. I do this by using a large-eyed needle and some 5 cord through the eye of the loop and then through the eye of the needle and start pulling.

Does that make sense to you? If not, send me an email to my private email address & I will attach some photos.

JerryBaumchen

PS) I have developed a procedure for making soft links using only this method; no sewing. You going to be at PIA/Reno, I could bring one along to show you?

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Hi Jerry,

Okay, I think I understand now.

But you know what? I think I have a simpler method.

I am attaching a PDF of the method I use. You'll see that it is similar to the JumpShack method, but when you pull the loop through, you will only pull it through a single layer of the line you are using. I think this makes it easier to do and less bulky.

Please let me know what you think.

Sadly, I won't make it to Reno. I am bummed out by this, but some of our business interests here require me to stay nearby.

I am still hoping to manage a day trip, but it is not a big possibility.

Anyway, take a look at the PDF I've attached, please, and tell me what you think.

-paul

There should be 4 PDF files attached.

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Hi Paul,

Page 3 took me a little while to understand but now I see it; you are pulling the loop at the bottom of the line back through the 'hole' that you have in the running end.

It does look a little bulky at first but it seems to smooth out.

Send me an email to:

jerrybaumchen(at)verizon(dot)net

and I will send you a copy of the soft link procedure ( it is a rather long MS Word document ). SKYDIVING magazine had planned on running it as an article but they are now defunct. :S

JerryBaumchen

PS) I may have to play around with your procedure to see if I like it. :P

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Quote

I did try it with cypres closing loop material and it worked great - I was able to hang on this loop from sealing. :P
Can you do a canopy relining with this methods ? Has anyone tried it ? What about dacron, and vectran do they work as well ?




I think you probably meant to aim your post at me, so I will reply.

I have used this technique on other lines. Dacron lines, being generally thicker, are the hardest of all.

I don't make any claims to the advisability of this technique on all line types. I have used it on Spectra and Dacron, and I found it in the first place on a canopy with HMA lines (IIRC). YMMV.

I will not suggest using it for the loops needed to reline a canopy.

I am not a Master Rigger, and I am not allowed to reline a canopy (at least not unless I am under the supervision of a Master Rigger).

That said, some linesets that come from the manufacturer, PD for example, would not be compatible with this method. The cascaded lines in a PD lineset have the cascaded B and D lines sewn in. You could not make the loop on the free ends of the B and D lines because they would have to be lark's headed around the attachment tab already, so your could not push the flattened loop through the second hole.

I suppose that if one was making his own lineset, it could be constructed using this technique and have no sewing at all. If the lineset is not cascaded, it would be a simple matter. If it was cascaded, a similar technique could be used to join the cascades after the loops were attached to the canopy.

But this is way beyond anything I have tried or might suggest.

I have only used this technique to make loops on steering lines, and I don't say it works for anything else.

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I have already relined 4 parachutes with Jump Shack’s sewless fingertrap. One of them with cascaded lines (Vectran) and the other ones with continuos HMA. All steering lines were made with the same technique but different material (Dacron or Microline).
My Cobalt 150 has about 400 jumps with this line set. Opens and flies like a dream (all the others too).
Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

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Hi Ronaldo ( my Mech. Engr. compadre ),

I haven't looked for a while but doesn't JumpShack say to lock/pierce the line twice? Yours looks like a single lock/piercing at each location.

I double lock/pierce whenever I use this procedure.

JerryBaumchen

PS) The internet is a great way for us to communicate, educate and assist one another. However, as these procedures get easier one begins to wonder how many folks will start doing their own relining to their canopies and then the troubles begin. One can only hope that relining will continue to only be done by experienced riggers.

Just an odd thought of mine; disregard as you choose. :P

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You're right about the double lock but I believe it is not necessary if you leave enough line inserted (at least 3” as recommended). I have checked most of the lines after about 300 jumps and they showed no sign of change in length (line length was checked under tension with a scale). Of course it wouldn’t do any harm to do it, only double the work.
You’re also right about spreading out this information and the possible bad consequences. I will ask the moderator to remove the post or at least the pictures.
Safe skies

Ronaldo
Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

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Did anyone see soft links done with no-sew fingertrap method ? They seam like easy thing to be done at home (if they have more than 3" between loops if not they could pass 3 or 4 times trough lines) ,...
I plan to use spectra 1000 lb and to do 2 insertion points per fingertrap just like Jump Shack suggests.
I would make 5 same soft links and one would be tested in pull test machine to see results.
Is somebody interested in jumping them :ph34r: ?

P.S. When relining do you have to create some tension on the line to correctly measure length of spectra 720?

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Hi jerolim,

This is exactly what I have mentioned up-thread.

I have a complete, detailed procedure on how to make them including how to install them.

The MS Word file is way too large to attach to any post here.

I have asked Terry Urban to see if it might be possible to get it up on the PIA Rigger's Forum; and he is looking in to that.

In the meantime I am sending out copies to anyone who wants a copy. I will bring a copy with me to PIA/Reno ( I'm leaving for Reno in ~ 20 minutes ) and people can make copies there.

If you want a copy of the procedure, send me an email with your snail mail address.

JerryBaumchen

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Hello Eric,

Thanks for letting us know how widely used this technique has been.

As I said, I reverse-engineered the technique when I found it on a parachute.

It certainly seemed to me to be an extremely elegant solution to the problem. But I'd never seen it in any text or manual, so I have been cautious in its application.

I am not sure from your post, has PdF used it for line attachments to the canopy as well as loops on steering toggles?

Again, thanks!

-paul

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