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DIY RSL ring add-on

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Pretty cheesy sewing.
I doubt if that would pull a ripcord.



okay - for all of those that have poo pooed so far -

WHY is it bad? I'm looking at the stitch pattern - machine was working good - looks like enough stitching to pull 22 lbs. Other than it looks like crap - what is wrong with it? Why do you not think it would work?

Educate me here. (remember that whole education not regulation thread in the USPA forum?)
Scars remind us that the past is real

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If I'm understanding what I'm seeing it's all on one side of the webbing. It would tend to point load at one corner and would tend to try to peel off. The stitch density isn't very high and it might have trouble resesting that type of failure. Better to samwitch. Remember an RSL may see higher peek loads then 22 lb. they tend to pull at odd angles and with negative machanical advantage. An RSL should fail below a certin point to avoid trailing a main canopy but that loop looks really cheasy. Look just go get some one to slip it in to the riser and bar tack it for you, OK. And you might want to erase the thread unless you want people to continue to make fun of you. Yah, it really is pretty bad and I'm just trying to help you here so don't go showing that to any one else bragging about your sewing till you get it fixed.

Lee
Lee
[email protected]
www.velocitysportswear.com

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Did you use a machine? It almost looks as if it were hand sown.

It just simply looks sloppy. An RSL should be treated as a backup device, but it's still a possible life-saving device, and should be treated as such. Are you willing to potentially put your life on the line with some stitching that you aren't completely sure can pull 22lbs? For me I wouldn't be satasfied unless that RSL ring can support >100lbs. You don't want to be in a situation in which you need an RSL, and have it fail you.
Skydiving: You either learn from other's mistakes, or they'll learn from yours.

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Question for riggers regarding this:

The ring is sewn to the main riser (not FAA regulated) but, since it's purpose is to pull the RSL lanyard attached at the other end to the reserve cable or pin, does this alteration require (legally) sign-off by a Master Rigger or the Manufacturer?

-dp

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If I'm understanding what I'm seeing it's all on one side of the webbing. It would tend to point load at one corner and would tend to try to peel off. The stitch density isn't very high and it might have trouble resesting that type of failure. Better to samwitch. Remember an RSL may see higher peek loads then 22 lb. they tend to pull at odd angles and with negative machanical advantage. An RSL should fail below a certin point to avoid trailing a main canopy but that loop looks really cheasy. Look just go get some one to slip it in to the riser and bar tack it for you, OK. And you might want to erase the thread unless you want people to continue to make fun of you. Yah, it really is pretty bad and I'm just trying to help you here so don't go showing that to any one else bragging about your sewing till you get it fixed.

Lee



well - first off - I didn't sew it. There are several things I would (and have) done differently. I was just asking those that were saying bad job to expand on their post rather than just say bad job - remember the whole educate not regulate theme?

I would have folded the material where it goes through the ring (similar to how mlw is joined to a hip rig), sandwiched it and used either a bar tack or zig-zag stitch on it.
Scars remind us that the past is real

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Question for riggers regarding this:

The ring is sewn to the main riser (not FAA regulated) but, since it's purpose is to pull the RSL lanyard attached at the other end to the reserve cable or pin, does this alteration require (legally) sign-off by a Master Rigger or the Manufacturer?

-dp



....................................................................

Correct for TSO C23B - which does not mention RSLs.

However, TSO C23D makes harness manufacturers responsible for RSLs and they must pass a 600 pound proof load.
Remember that RSLs often get "jerked" as the main riser leaves. RSLs also pull at weird angles, so must resist peeling.

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Question for riggers regarding this:

The ring is sewn to the main riser (not FAA regulated) but, since it's purpose is to pull the RSL lanyard attached at the other end to the reserve cable or pin, does this alteration require (legally) sign-off by a Master Rigger or the Manufacturer?



It has to done by a master rigger or someone under his supervision, main or reserve.

TSO'd stuff needs either the manufacturer's approval, the FAA's approval, or both.

Things related to a main needs no formal approval, but still needs to be documented only if it effects the operation of the reserve---(RiggerPaul corrected me on this)

I also think that it being connected to the RSL makes it a TSO issue.

From "Parachute Alterations"


B. Any change to the configuration, method of
operation, or method of packing the main parachute, up to
and including the main canopy attachment links or the male
end of the quick release fittings, is a main pack alteration.
Any main parachute alteration that affects the strength or
operation of the auxiliary parachute , including the harness,
must be regarded as an alteration of the auxiliary parachute
and handled accordingly.



Cheers,
MEL
Skyworks Parachute Service, LLC
www.Skyworksparachuteservice.com

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Pretty cheesy sewing.
I doubt if that would pull a ripcord.



okay - for all of those that have poo pooed so far -

WHY is it bad? I'm looking at the stitch pattern - machine was working good - looks like enough stitching to pull 22 lbs. Other than it looks like crap - what is wrong with it? Why do you not think it would work?

Educate me here. (remember that whole education not regulation thread in the USPA forum?)







Looks like it was sewn with F thread (11 lb breaking strength) as opposed to 5 chord (40 lb breaking strength), also about 6 stitches completly missed the 3/4" T 4. There look to be about 25 to 28 stitches all told, now some math: 11 lb x 28 (best scenario here) = 308 lb, take away the 6 or so stiches from the pattern and you come up with 11 lb x 22= 242 lb about 50 lb less. The fact that the T 4 has been compromised in at least two ways makes it
more vulnerable to shredding as it comes under a quick and heavy load, the stitching that runs off the edge of the webbing will destroy it's selvedge edge and allow it to seperate and the fused (melted part first photo r/h side) part of the webbing has been weakened to the point that it cannot be counted on to live up to it's rated load.

All of this "static" evidence coupled with a dynamic load and a twisting motion of the riser as it releases would in all likelyhood cause the joint to fail or come very close to it, making it a one time use product. It is unlikely that it would be viable after more than one use. It's poor engineering not to wrap the webbing loop around the riser body with at least one full side overlap, even sandwitching the loop between the webbing ply's and sewing it with 5 chord is a damn sight better than what we see.

hope that helps explain the forensics behind what we see here. Oh, and it's damned ugly too!!!!!!



Forgot to add: As it's only swen to one leg of a T 17 (2500 lbs) riser it would probably compromise that too.

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