Zigzag: Maintenance failure leads to accident

This mishap illustrates a small vulnerability in these types of mechanicals like the zigzag, rope runner and akimbo where the upper bird/wrench (rope bending element) provides a pilot force which drives the action of the lower section be it a rope pinch or flexible bending rack like the zigzag has. Disable the top, the bottom stops working. This undoubtedly lead to the addition the tiny engagement springs to ensure the self engaging action begins - if you're lucky, fit and friction alone starts the engagement like the rope wrench before the stiffy tethers. Yes Kevin's gizmo has three elements wrench plus two pinches but both pinches are piloted by the wrench.

In contrast a wrench plus hitch combo won't free fall if the wrench loses either its position retainer rubber on the stiffy or friction fit, the hitch self engages independently.

In the case of a branch coming down your line and activating your system there is some extra protection I think in that the odds of continuing to fold down your wrench and also successfully modulate your hitch are lower than just hooking the top element tip.
 
I have run ZZ and Akimbo into branches on ascent, and a couple of times I've dropped a few inches... never any more. I've done it with a hitchclimber setup in the past, as well. But, I agree, the RW/prusik combo seems pretty much immune to that. The ZZ/Chicane combo also seems to add protection from that rare occurance.

I've never seen a falling branch slide down a climb line and activate a multicender... the occasional twig sized thing, but they never did anything at all to the devices. I did, however, have a cut branch dropped onto a speedline spin around and twirl all the way down the damn speedline rope until it fell back off a few feet before landing. That was pretty freaky. So, I know this is actually possible... but, I think it's probably pretty damn rare, from my own experiences.
 
Only time I've had a multicender collapse, I foolishly clipped a speedlines sling above my zigzag to hold it for a moment and it had enough weight to collapse it and send me for a bit of a ride.

I've also gone to sit back on a hitch and had it not bight completely.

Neither is perfectly safe all the time without attention being paid to its use
 
Very, very true. I have to force myself to be diligent. If I take my eyes and hand off the multicender, I make a point to look right at it before I grab it again. I've grabbed it and stepped off the limb a couple of times without looking, and there was slack. No fun taking the slack out that way.
 
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Well, took my first rip with the new Zig Zag today. Most of my end-of-March work dried up, and had I know that was going to happen, I might have saved the few hundred bucks.

Until I tried my Zig Zag, like actually worked with it. WOW. I can't believe how much fun it was. It seemed to be more sensitive than my VT- but I think it's just going to be getting used to it. I totally wish there wasn't a friggin' apocalypse and I could actually use the thing this week! Big swings. Smooth slack tending. A blast!

Course, i may have to pawn it off on Treebuzz for toilet paper, but wer're not there yet.

Until then, there's always tree hunting/rec climbing with the boys!!!
 
I am so glad the report of an accident involving a ZZ turned out to be a maintenance issue. Not being able to trust my equipment when I'm hanging on a rope seventy feet up would take a lot of the fun out of climbing.

Question for Timmy, or anyone else: What's a VT? I can't find any climbing device in the catalogs that would have those initials.
 
Winchman said:
I am so glad the report of an accident involving a ZZ turned out to be a maintenance issue. Not being able to trust my equipment when I'm hanging on a rope seventy feet up would take a lot of the fun out of climbing.

Question for Timmy, or anyone else: What's a VT? I can't find any climbing device in the catalogs that would have those initials.
Click to expand...
Valdotain Tresse, a friction hitch.
 
Kind of raises the point of the merit in not needing a helper spring by having tune-able bollards in the first wrench section so you can eliminate reliance on the spring. Think ZK-1. Less convenient, bit of ascent drag, but a higher level of inherent safety. Anyone else notice the first link of the zig zag has the same geometry as a super mini wrench? Been bugging me for a long time, had to finally say it. Kevin, your genius concept lives in so many places. I remember some of the design machinations on the akimbo regarding the upper wrench section. It seems the convenience improvement in self tailing and not needing adjustment was at the expense of de-improving device safety, regarding the pilot spring in all the devices. The zig zag pilot spring anchor was also the failure point of the cracked zig zags.
 
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