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imsparticus

correct method for three ring inspection

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ok, when the loop from my three rings is tight holding the top ring against the riser gromet because the hard housing is free taking up all the slack of the loop pulling it away and i apply tension to the riser i do not have metal to metal between the top ring webbing and the middle ring however when i align the hard housing with the riser grommet to give the loop slack to the top ring and i then apply pressure by pulling on the riser the top ring is no longer hard up against the riser grommet all three rings are parallel and have metal to metal contact.

I would just like to know by this description do you believe these risers are servicable or not? it seems i get 2 different results depending on how the hard housing is positioned in relation to the riser grommet when you apply tension to the riser.

Thanks and i hope that made sense

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For the 3-ring system to function properly and reliably (it is a release), the rings must rest one on the other (small on middle, middle on large).

From what you described, it seems your 3-ring system isn't properly configured. Show your rigger and allow him to inspect the risers and 3-rings. He will be able to determine if the risers are airworthy or not.

Photos would help. ;)

"Even in a world where perfection is unattainable, there's still a difference between excellence and mediocrity." Gary73

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they are metal to metal when the hard housing lines up with hole in the riser for the loop to give it some slack and keep the top ring off the grommet which is the configuration it is in when you are open and there is load on the risers.
but if you take away the slack in the loop by moving the hard housing away from the grommet (as it usually is when static or only light loads) pulling the top ring to the hole in the riser they are not.

anyhow a top ring that touches the grommet is not sevicable (but only while it is in the correct configuration and under load). the three rings should lay parralell to one another under load due to the extra lenghth in the loop which leads me to believe that when you check a 3 ring you should be lining up the hard housing hole with the hole in the risers to put them in the correct configuration (giving max travel from the loop to top ring) to see if they are metal to metal and parralel, how many people actually do this and then snag a riser for not being metal to metal or top ring toughing grommet when infact it is a perfecly servicable riser. capish

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your right pics are much easier to explain

first one is the housing away from the riser hole/gromet config no metal to metal contact on the top ring webbing to middle ring, second one is the "loaded" (canopy open) config metal to metal on rings and housing in line with riser hole/grommet.

i have tension on the risers for both pics

so what do you guys think?

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The 3-ring looks fine. It's good that you show it under tension but it's not under load - that is, you need to see how it looks when you're under canopy.

I see why you are concerned about the small ring but there doesn't seem to be an excess of webbing-loop. The loop appears to be new and very firm. The white loop appears to be fine.

Your risers appear to be new. With use and age the webbing will soften and the rings will sit more naturally.

In response to your initial question, the correct method for inspecting the 3-ring, I'll copy something here directly from my safety day presentation. I hope it's helpful

PERIODIC MAINTENANCE

1. Every month operate the 3-Ring Release System on the ground. Extract the release cable completely from the housings and disconnect the risers.

2. While the system is disassembled, closely inspect it for wear.
- Check the white locking loops (the ones that pass over the smallest ring and through the grommet) to be sure they aren't frayed.
- Check the Velcro on the release handle and main lift web to insure that it adequately holds the handle.
- Check the stitching, including that which holds the large ring to the main lift web and the hand tacking that prevents the release housings from sliding through its keeper. (This keeper is located a few inches above the padded release handle).

3. Take each riser and vigorously twist and flex the webbing near where it passes through each ring. The idea is to remove any set or deformation in the webbing. Failure to do this might make the release hesitate when activated in response to a low-drag malfunction such as a streamer.


3-Ring Inspection (SIM Sec 4, Cat D)

1 - ASSEMBLY
a. Each ring passes through only one other ring.
b. Each ring sits atop the lower and larger ring.
c. The white retaining loop passes through only the topmost, smallest ring.
d. The white retaining loop passes through the cable housing terminal end.
e. The yellow cable passes through the loop and secures in its housing.

2 - CONDITION
a. Look for wear in the loops holding the rings.
b. Look for wear in the white retaining loop.
c. Check the fittings on both ends of the cable housings for security.
d. Look for kinks in the yellow cable, which may indicate a problem with hard openings or the 3-ring assembly.
e. Look for nicks, kinks and burrs on the yellow cable - especially on the end.
f. Check the front and back of the riser webbing for fraying or strains around the grommets.
g. Look for broken or loose tackings on the cable housings.
h. Check riser inserts (for cutaway cable ends) if installed.

3-Ring Maintenance (SIM Sec 4, Cat H)

1. Owner maintenance of three-ring release system:
a. Disassemble the system every month to clean the cable and massage the ends of the risers.
(1) Nylon riser webbing develops a memory, especially when dirty.
(2) When disassembled, twist and massage the nylon webbing around the two riser rings.
b. Clean the cables.
(1) Most three-ring release cables develop a sludge-like coating that causes them to bind, increasing the required pull force.
(2) Refer to the manufacturer' instructions for cleaning.
"Even in a world where perfection is unattainable, there's still a difference between excellence and mediocrity." Gary73

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sorry koppel but my CI is not interested in a riggers opinion and has already defined them as unservicable as there is no metal to metal in pic 1. ( the config he had the risers in when he checked them).

what i ment by "correct method" was whats should the correct orientation/placement of the hard housing grommet in relation to the riser grommet be when carrying out the inspection as different placement of the hard housing in relation t the riser grommet yields different results.

it doesnt say directly in words on the APF service bueltin however the diagram clearly shows hard housing grommets hard up against riser grommets.

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no disrespect intended koppel just the reponse i got from him, I actually have the risers signed on my packing card as per the sb which he has also rejected. however i respect his view which is why i am seeking further clarification

seeing as your a rigger care to enlighten me/us on the placement of the hard housing when tensioning the risers for inspection as per the apf sb:

ei, should they be:

1, doesnt matter metal to metal regardless (ie, in both positions)

2, hard housing grommet in line and against riser grommet (as in the second pic)

3, hard housing grommet pulled away from riser grommet (as in the first pic).

im just raising the question as the orientation of the hard housing affects the outcome (in some risers)and seeing as correct riser construction is such a hot topic in oz at the moment I think there possibily could be alot of sevicable risers out there being a little over scrutinzed due to missunderstanding of the sb. ofcouse i could be wrong and have to eat my slice of humble pie (oh please not again it tastes like shit)

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You can measure 3-rings while loaded or you can measure them laid out flat, but trying to measure them somewhere in the middle is just confusing.

When measuring risers on a harness, pull on them (20 pounds/10 kilograms) until the end of the hard housing lays against the back side of the riser. Check that rings lay parallel, metal-to-metal contact, plenty of slack in white loop, etc.

To measure risers flat, get a copy of the RWS/UPT 1998 manual, disconnect your risers from your harness and lay them flat. The white loop should be as long as tape holding the smallest ring and you should also check how far the smallest ring is from the bottom and grommet spacing (as per 1998 manual). Again, these measurements are taken with a bit of tension - pulling rings towards the bottom of the riser.

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Quote

Not to be too pedantic - but that APF SB has been replaced with Version C - in March. http://www.apf.asn.au/documents/pdf/Service_Bulletins/APF/APF_SB010801-C.pdf

No change to your intial question, however just wanted to let you know of the up-date. :)



Actually, I think that the distinction between the two versions of the APF document is quite important.

The "C" version includes the statement "Under moderate tension the rings should overlap each other and maintain metal to metal metal to metal contact between each other", and then goes on to give the other details.

I'm not completely sure what that riser would look like if some real load had been applied.

But I think there is a chance that it would have changed the verdict on these risers.

The "B" version of the document implies that the riser should look like the picture without intervention on the part of the inspector.

Clearly, the first picture that the OP offered did not meet that requirement.

But the second picture, where the grommet is held against the back of the riser, was a lot closer.

The "C" version specifically says you should apply some tension to get the thing to look right.

Neither picture the OP posted really meets the criteria for inspection as put forth in the "C" version of the document.

But that second picture comes quite close. So I wonder what it would have looked like if the required tension had been applied.

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Thanks for the new pictures.

I don't have a problem with either using or retiring the risers at this point.

On the one hand, there is metal-to-metal contact on all the rings. And that's what the original question was about.

One the other hand, the small ring is not parallel to the riser in either case. And that's called for in both versions of the APF document.

Would I jump them myself? Probably.

Would my advice to another owner be to replace them? Probably. I certainly wouldn't want my advice to be the source of a problem for him, so I would tend to err on the side of replacing anything that's in a gray area.

Replacing gear that is in the gray area is not a bad idea, just sometimes an expensive one. Kind of like insurance. Seems foolish if you never use it, but brilliant when you need it.

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