Check this out!!!

That's just scary! That was a factory rope bridge I presume?

I think when I replace my rope bridge on my Cougar, I may just go with good ol' polyester inside and out.

If that is a technora core, isn't technora 'self-abrasive'? If so, it would appear that loading frequently at the center of the bridge may have accelerated the self-abrasive action.

Wouldn't manufacturers know about stuff like this by now???
 
DAMN Jeremy!
I think Ill be replacing my bridge alot more often.
Glad you are ok bro. Thats the scariest thing I have seen in a long time.

Im going to your teamspeak channel right now....you are so dead.
 
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Don't toss it!! Bring it to TCI and put it on display. It's a perfect example of the fiber characteristics and why a climber can't be complacent with their gear.

You are a lucky man.

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Excellent point! Bring it to Expo and have the manufacturer check it out.
Goes to show ya how important it is to know your rope fibers.
I'd be interested to know what the fiber is. It does look like the old 16 strand "Tech cord". The new one is 30% technora, 30% vectran, and 40% polyester. This product needs to to wear and abrasive tested before it is put to commercial use.
Glad you're OK and you thought about splicing up a new bridge.
 
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Yikes! Damn good timing in the bridge change out. I'm goin to change mine out right now....

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I'm going pull the covers off a few old prusik's just to see how the core's look. Their rather well used. If anything not right comes to light I'll take a pic or two and post on it.
 
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If you don't mind my asking....how did you splice that piece up? How far did you cross the legs over in the middle? How long were your tapers in the middle? How many taper strands did you pull prior to the initial bury?

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The bridge was spliced at the 1st Spring Spicing Symposium, it was around March of '08. So all the specs were spot on. It was my fault for "zero" inspection of the core. I just figured as long as the spliced eyes and cover looked ok, then the cordage inside should be ok. So lesson learned.

I ordered a new bridge from Knot & Rope Supply. It was here in less than 24hrs. Sweet!!

Things changed:
Length of bridge,
newer tech cord with Technora/Vectran mix to increase the durability. I also added two rings to widen the bend radius. Lastly, check, double check and triple check all gear.

As for the the bridge, I sent it to Knot & Rope Supply. There going to check it out and give me some feed back.

Here is a few pics of the new one....oh yeah!!!!

4017579875_2763323cb9.jpg
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Just to brief everyone here, this bridge is made out of 3/8 tech cord, which has a avg. break strength in the 15 - 16,000 lb. range. So strength wise it is plenty strong.

This bridge has a full cross over of course and a nice smooth taper so there are no lumps or bumps. Having the larger diameter (in the 1/2" range) should radius match a little better with any rings or carabiners that might be used on the bridge.

As you can see, the eyes are really tight, just about as tight as we could make them. This is so that they will fit precisely on the shackle being used on this harness. Some customers request a larger eye for a girth hitch, while others want the tight eye. Both work equally well.

That cover on there by the way, is ARC, which stands for Abrasion Resistant Coating. This is something that our performance sailors use but it works great for these bridges. Basically, it is similar in touch and feel to HRC.
 
"The bridge was spliced at the 1st Spring Spicing Symposium, it was around March of '08. So all the specs were spot on. It was my fault for "zero" inspection of the core. I just figured as long as the spliced eyes and cover looked ok, then the cordage inside should be ok. So lesson learned."

That's extremely quick deterioration of the internal cord. Although the flag has been raised about the failure the the short duration to failure should be recognized even more so.
 
Damn Jeremy! How long have you been using that bridge?

I think I'll strip mine down at the Fall Climb which will be exactly one year of use. Mine is two Vectran bridges inside a jacket from some kernmantle rock rope.

Vectran is a hi-mod too right? Do all hi-mods wear like that, or just Technora?
 
Whoa. I am glad you decided to make a new bridge that day and measure up the old one. I had a bridge that is made of the same stuff on my saddle and replaced it with something different after the last thread that talked about the tec cord bridge breaking. Now, I am NOT second guessing my decision to do so. Makes me really look at rope and application way more closely, not just tensile strength. Glad your OK man.
 
OK, we just got done looking at the section of rope that is in question here.

From our initial assessment here is what happened:

This bridge was made from a product called Tech Cord from All Gear, (not to be confused with the 5mm product from New England Ropes also called Tech Cord, which is a whole different rope).

The rope that was used on this bridge was the old style of Tech Cord that was made with 100% technora, which seems to have a bit more self-abrasion properties compared to other synthetic ropes.

The new Tech Cord from All gear is made with a 50/50 mix of Technora and Vectran. The Vectran fibers have more lubricity than Technora, and mitigate the abrasion caused by the fibers rubbing closely together with great force.

In the case of this bridge, you can see where the constant wear action at the midpoint of the rope caused the micro abrasion to gradually wear the rope down.

As a footnote, Technora is a fiber that isn't very resistant to UV light. Covering it with a sheath of some type (like on this bridge) is a pretty common thing. It is something we do when using this rope on high performance sailboats. However, the spliced eyes are not covered, so during your daily check of your climbing harness, make sure you include this area in your inspection.

Strength wise however, this product is more than enough for a bridge.
The 3/8 cord has an avg. break strength of well over 10,000 lbs.

Hope that clarifies this a little bit.
 
Just to throw one more thing in here on that cord, keep in mind that this rope has zero melting point.

Instead, it will break down at around 900 degrees Fahrenheit, but you shouldn't push it past 4-500 because of strength reductions.

This rope makes an awesome prusik cord....
 
Ya I'm playing around with the idea of two rings and double rope bridge. It shouldn't be much different than the original but I sure feel safer looking down at it everyday.
 
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