degradation of 'kevlar' type trigger wires

I'm wondering how resistant these trigger wires are to sun, abrasion, and chemicals. For anyone that has had them fail, did they do so all at once, or slowly deteriorate (did you see it coming?)

Specifically: I recently found a new 00 mastercam in the trees of my local crag. Cam lobes were seized with rust. I figured it was a lost cause but got out some solvent (mainly WD40) and tried working them with pliers. After a few attempts I actually got the action working pretty much like new, and am just about ready to start falling on it, but I'm wondering if I should replace the kevlar trigger wires. From what I can tell I should be fine:
www2.dupont.com/Kevlar/en_U…
as it can handle 1000 hours of soaking in gasoline, and 500 hours in kerosene, but that's not exactly the solvent in WD40, and I'm no chemist.

I also read that metolius actually suggests spraying down cams with WD40 before taking them to seaside crags. I figure they would make some note about covering the trigger wires if it was an issue, but would be nice to get more direct confirmation that there is minimal harm, if possible.

Any procrastinating engineers, chemists, or people experienced with this material out there?

Thanks!

I don't know about the durability of "Kevlar" trigger wires, but Metolius will replace the trigger wires relatively cheap. If you are concerned, just ship 'em to Metolius for rewiring.

If the chemicals hurt the trigger wires, you can just replace them. I wouldn't get the WD40 treated cams near your rope, slings, or quick draws though, unless the chemicals have been completely cleaned off.

I bootied a cam off of alpine climb in co. it had been out long enough that the anodization not covered by the sling on the carabiner was visibly faded. after I removed it, I got it working smoothly with days of soaking in CLR WD40 and other nasty solvents.

I'd use it. worst case the trigger wires fail and you leave your free cam.

Are trigger wires really safety critical, though? Assuming you could somehow retract the cam lobes, wouldn't a cam with ZERO trigger wires still hold a fall? I think that's how the mechanics of a cam work. Or am I crazy?

If that is true about trigger wires, then the cam is fine, even of they are weakened. When they do, replace them or or retire the piece. No biggie.

Trigger wires are not safety critical. A broken one would mean a cam that's a PITA to get out, or worst case not possible to properly place, (and then you just don't place it). I'd climb on it with no hesitation.

Its a 00 Mastercam - its not supposed to hold much force anyways.

I dont know much about the Master Cam trigger wires other than none of mine have ever broke. However, with regard to Kevlar, the material has poor resistance to UV, and it degrades from sunlight exposure alone. Typically any Kevlar product that is exposed to the sun is enclosed in some form of casing to protect it from the sun. Exposed Kevlar can turn from yellow to brownish with less than 100 hours of direct sunlight exposure. Kevlar also has relatively poor flex-fatigue properties because the material is supposedly abrasive (as I have read, never confirmed myself). Supposedly the material starts to break down after repeated bending as a result of the fibers wearing at each other.

That said, I have some 10,500 lbf 1" Kevlar webbing that I use for slacklining, and I often tension it up to 3500 lbf and in direct sunlight, and the material has not failed. It has turned brown though for whatever that is worth.

Thanks everyone!

Ya, I realize the fail mode of trigger wires won't hurt. But I wouldn't want to lose a perfectly good cam when I could easily replace the trigger wires beforehand. I'm also not really into replacing the trigger wires if there is no reason to though. Woe is me eh?

I see no discoloration and everything I've read tells me it should be fine, so I think I'll just try it.

Also:

Steve Jones: WD40 is a mix of oil and solvent. The solvent evaporates soon after application and just leaves the oil, which shouldn't affect nylon or other gear accept for making it more dirty. Otherwise I guess Metolius wouldn't recommend it as an alternative to their own lube.

Matt N: The 00 is still rated at a whopping 5kN! It's not my favorite thing to do, but I've definitely taken some solid falls on my smaller gear.

20kN: Awesome graph, thanks! Any idea on the source of it?

Thanks for the correction, someDuder. According to Sterling Ropes, "nylon's strength is not greatly affected" by gasoline and motor oil:
climbing.about.com/od/climb….

Pretty sobering to see how much strength is lost in wet ropes.

someDuder wrote:Thanks everyone! Ya, I realize the fail mode of trigger wires won't hurt. But I wouldn't want to lose a perfectly good cam when I could easily replace the trigger wires beforehand. I'm also not really into replacing the trigger wires if there is no reason to though. Woe is me eh? I see no discoloration and everything I've read tells me it should be fine, so I think I'll just try it. Also: Steve Jones: WD40 is a mix of oil and solvent. The solvent evaporates soon after application and just leaves the oil, which shouldn't affect nylon or other gear accept for making it more dirty. Otherwise I guess Metolius wouldn't recommend it as an alternative to their own lube. Matt N: The 00 is still rated at a whopping 5kN! It's not my favorite thing to do, but I've definitely taken some solid falls on my smaller gear. 20kN: Awesome graph, thanks! Any idea on the source of it?