Riser damage... anyone seen this sort before?

[parachutist 1]

These are relatively new risers with approximately 75 jumps on them. They're developing some damage and I'm not sure what's causing it. It looks like the webbing is getting melted somehow. I replaced the previous risers, which had similar damage. The slider grommets are in pretty good shape, with a few minor dents but smooth inside surfaces. I only noticed this type of damage after replacing the spectra line set on my Vision 117 with HMA cascaded lines. I'm not sure if that line set change is related or not... may be just be coincidental.

All pictures below are of the front sides of front risers and front sides of rear risers. The back sides of all risers are fine... so it appears to be getting damaged only where the slider grommets rub against the fronts of the risers, but it's not the typical fraying that I'm accustomed to seeing, caused by rough inside edges of grommets, so I'm not sure where to go. Any ideas?

http://www.funjump.com/riser_damage/IMG_0004.jpg
http://www.funjump.com/riser_damage/IMG_0009.jpg
http://www.funjump.com/riser_damage/IMG_0011.jpg
http://www.funjump.com/riser_damage/IMG_0014.jpg
http://www.funjump.com/riser_damage/IMG_0017.jpg
http://www.funjump.com/riser_damage/IMG_0019.jpg

Chris

[hajnalka 0]

2nd to last pic shows some pretty sharp slider grommet dings.

Maybe your slider grommets are nickle-plated brass? These are fine with Spectra lines, but when you go to HMA you need stainless slider grommets. From what I've seen, HMA will tear up nickle plate grommets pretty fast and that can cause all kinds of damage.

[airgord 1]

Are you using metal links? Would like to see photos of the whole riser showing the damage side too.

[pchapman 261]

Odd. Don't know the answer.

The slider grommets do appear to be the stainless steel type, therefore appropriate to HMA. While there are slinks on the risers now, to get those strong dings in the slider grommets, they must have been once used with metal links without covers?

I'm not that experienced with such stuff, but the riser damage (and wide spread location) suggests high speed rubbing, not just a dinged slider grommet being pulled down. Are the fronts of the risers packed up against any rougher seams of the riser covers/side flaps or anything like that??

But what about the red flecks around some of the riser burns? From the rig, or from the slider? One couldn't possibly pull ones' slider down (and back up when packing) violently enough to burn the risers??

Or could it all be from some one time incident on the ground, something getting dragged across the risers? And no line twist incident on some opening that might have burned risers against themselves (maybe with a bit of slider fabric thrown into the mix)?

[parachutist 1]

Quote

Odd. Don't know the answer.

The slider grommets do appear to be the stainless steel type, therefore appropriate to HMA. While there are slinks on the risers now, to get those strong dings in the slider grommets, they must have been once used with metal links without covers?

I'm not that experienced with such stuff, but the riser damage (and wide spread location) suggests high speed rubbing, not just a dinged slider grommet being pulled down. Are the fronts of the risers packed up against any rougher seams of the riser covers/side flaps or anything like that??

But what about the red flecks around some of the riser burns? From the rig, or from the slider? One couldn't possibly pull ones' slider down (and back up when packing) violently enough to burn the risers??

Or could it all be from some one time incident on the ground, something getting dragged across the risers? And no line twist incident on some opening that might have burned risers against themselves (maybe with a bit of slider fabric thrown into the mix)?

I bought this canopy used... the dings were there when I got it. I assume they were caused by hitting metal links at some point

The rig has no rough edges inside... it's a standard Altico Dolphin.

The red spots are from the red slider. The slider has some shredded areas on the right edge and left edge. I'm not sure how that red fabric is getting transferred to the risers.

I'm sure the cause is not a one-time incident of risers rubbing against each other because I've watched the damage progress over the last couple months.

[skymik 0]

For the Grommet damage I think that has caused a the control line ring's in a slink ..... and the risers I saw similar damage with openings off, the riser touch the container reserve

http://www.skymik.it

[mjosparky 3]

From what I can see in the pictures it appears that the damage was heat induced. That would lead me to believe it is caused by the slider slamming down over the riser at a very fast speed.

Sparky

My idea of a fair fight is clubbing baby seals

[phastasphuk 0]

A flapping slider would rub against the front sides of the risers.

chris

[rwieder 0]

Quote

Are you using metal links? Would like to see photos of the whole riser showing the damage side too.

-Richard-
"You're Holding The Rope And I'm Taking The Fall"

[punkd 0]

I ended up with some similar dings in my slider grommets from using Aerodynes soft links. At first I didn't have the metal rings tacked down in place and they would always come out to the sides on opening.

http://www.parachut.fr/images/Soft%20links.jpg

[parachutist 1]

Quote

From what I can see in the pictures it appears that the damage was heat induced. That would lead me to believe it is caused by the slider slamming down over the riser at a very fast speed.

Sparky

This slider does come down fast. Canopy snivels for a bit with slider all the way up, then slider comes down fast enough to leave bruises on my knuckles sometimes if my hands are on the risers.

Do you think it could be the grommets are getting friction from the lines on the way down, enough to heat up the grommets, then hot grommets sit on the risers & melt them?

Chris

[rwieder 0]

Experiment by tading a slider out, install something
diffrent ie: size, style,something. If that freaking slider is coming down that fast, something's jacked up. I've had to figit a bit with sliders in the past. Are your lines in trim, canopy sound? It also appears you may not be stable at deployment. What size / mfg pc are you using? Do you think it could be Line Dump?


Good Luck.

-Richard-
"You're Holding The Rope And I'm Taking The Fall"

[RiggerLee 61]

Interesting pictures.
Yes most of the damage, the smooth glazing, looks like a riser being burned by a fast moveing slider.
And I've seen dings like that on sliders. Could be the slink or could be the toggle keeper ring. Depending on how they're set it can push the ring out to the side enough to be struck.
Some of it looks like line damage. Do you pull the slider fully behind your neck before unstowing your breaks? Ever grab the toggle and yank it lose from underneath the slider cause you're in a hurry, like to avoid a collision? or have you ever had a toggle knocked loose on opening? I'd like to see how you stow your breaks? one of the burns looks like the line being pulled around the riser at high speed. Maybe catching the red fabric in it?

Lee

Lee
[email protected]
www.velocitysportswear.com

[JohnRich 4]

Quote

I'm sure the cause is not a one-time incident of risers rubbing against each other because I've watched the damage progress over the last couple months.

This statement frightens the hell out of me. You've intentionally jumped damaged risers, and continue to do so while watching them grow worse. Unbelievable! You should not continue to jump these damaged risers! Replace them immediately, or we'll be reading about you in the "Incidents" forum!

My guess would be that the damage is from a rapidly flapping/vibrating slider rubbing against the risers, creating enough friction to melt the nylon fibers. It only takes about 375-degrees of heat to do that, and there is a high coefficient of friction between two pieces of nylon.

So to stop this from happening again (after you've installed new risers!), you've got to secure that slider so that it doesn't flap in the wind.

[mark 102]

Quote

My guess would be that the damage is from a rapidly flapping/vibrating slider rubbing against the risers, creating enough friction to melt the nylon fibers. It only takes about 375-degrees of heat to do that, and there is a high coefficient of friction between two pieces of nylon.

So to stop this from happening again (after you've installed new risers!), you've got to secure that slider so that it doesn't flap in the wind.

I have seen similar damage to two other sets of risers. In both cases, the jumpers collapse their sliders and stow in slider keepers.

The common denominators are Vectran lines and stainless grommets.

I also saw melted risers when I tried Tandem Slinks™ with EZ-384s (stainless grommets).

Mark

[parachutist 1]

Quote

Interesting pictures.
Yes most of the damage, the smooth glazing, looks like a riser being burned by a fast moveing slider.
And I've seen dings like that on sliders. Could be the slink or could be the toggle keeper ring. Depending on how they're set it can push the ring out to the side enough to be struck.
Some of it looks like line damage. Do you pull the slider fully behind your neck before unstowing your breaks? Ever grab the toggle and yank it lose from underneath the slider cause you're in a hurry, like to avoid a collision? or have you ever had a toggle knocked loose on opening? I'd like to see how you stow your breaks? one of the burns looks like the line being pulled around the riser at high speed. Maybe catching the red fabric in it?

Lee

Lee,

I collapse the slider, then pull it down behind my head, then unstow the toggles. I don't tie the slider down or have any slider keepers on the risers... it just stays behind my head. The brake lines are stowed on this rig by a few different packers at the DZ usually; methods vary slightly. They're Velocity risers with a small tape loop for holding thse excess brake line. Some packers don't bother stowing them, some fold them up and leave them in the keepers.
This is my backup rig.

My other rig (main rig) is packed by the same packers, and has the same model risers (ordered at same time as the damaged risers), with same brake toggles, etc... and those risers have no damage... they still look practically new. The canopy attached to my main rig is a VX109 with HMA lines... it has Dacron LSTs, while the backup rig has HMA LSTs

A couple times I've needed to grab a toggle and unstow it before doing anything else because of toggle fire or diving after opening. Those times I've just left the slider above the toggles for the rest of the jump.

Going back in this story a few months ago: The reason why I bought these new risers: the last pair had similar damage, except it was isolated to the very tops of the risers. I had some vet wrap on those risers instead of dive loops, and the slider always stayed at top of the risers because they couldn't go over the vet wrap. I figured the cause of the damage to those risers was that the slider was sitting in the same spot on the risers & aggravating the same area continuously. I thought pulling the slider down behind my head would alleviate that problem, but apparently not.

Chris

[RiggerLee 61]

Again it's hard to tell looking at pictures. Most of that doesn't look too bad. Those risers are ressin coated. I think a lot of that is just the slider slideng down and "pollishing" that ressin coated surface. The worst thing I see there are the "nicks" in that one rear riser. It looks more like a line burn. Maybe from a premi release. Maybe from being yanked lose with a slider stuck half way down over it. I can't finger fuck it from here but you might have to retire it. That one groove looks interesting. I'd keep an eye on how people are stowing your toggles, or better yet start doing that your self and take them out of the equation.

Lee

Lee
[email protected]
www.velocitysportswear.com

[LongWayToFall 0]

Newb here....

Can you feel the grommets after opening to see if they are hot enough to do that damage?

[parachutist 1]

Quote

Newb here....

Can you feel the grommets after opening to see if they are hot enough to do that damage?

It's worth trying. I always wear gloves though... I'll need to leave them on the ground for a few jumps

[irishrigger 31]

hiya,
i have seen simular damage before on a couple risers,and i also think it is line burn.i dont believe that this much damage could be caused by collapsing the slider after opening.
what i found in my cases was incorrect stowage of the risers during the packing.how do you place the risers into the container? also how much slack lines do you leave out? have you any damage to the bottom of your reserve tray on the corners? if you have i suspect that the risers have not been placed down the side of the container.and the lines should be neatly s-folded on the bottom of the tray. with about 16-18" of slack.
can you let me know what the main and container is? and please inspect inside the pack tray and the bottom edges of you reserve tray for simular damage.if there is you have your answer.
its hard to see how much damage is actually done to the riser,for peace of mind i would get a rigger to have a look at them,just to be sure.
rodger

[erdnarob 1]

Is one has thought about the type of canopy used and/or the packing method used as well ??

Learn from others mistakes, you will never live long enough to make them all.

[hookitt 0]

If you get a chance, take a picture of how you stow the toggles, and how you stow the excess line.

Also take a picture of how you place the risers into the container.

Take another picture of the corner of the the reserve tray where it's sewn to the back pad.

If I had the rig in my hands, I'm nearly certain I could figure out what's causing it but it's tough doing it online

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto