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Micro traxion progress loss on a body haul.


Original Post
Zach Raney · · Leadville, CO · Joined Aug 2014 · Points: 0

I’ve been thinking about this strange thing that happened in zion a few weeks back where i lost maybe 6in on a body haul. As in the pivoting “toothed arm” didn’t press on the rope when rope was being pulled through. There was no damage to the rope, i was just pulled forward when going to reset my jumar. Super odd and I’ll be calling Petzl. It worked fine the rest of the time but i haven’t heard of this or experienced it before 

-zach

Mydans · · Unknown Hometown · Joined Apr 2014 · Points: 70

I obviously wasn't there so this is speculation but if you rigged the haul so the device was oriented sideways and not allowed to rotate you could have inadvertently twisted the hauler which could have pushed the cam open.  Just one possibility and like I said without seeing the anchor its hard to tell.

ClimbingOn · · Unknown Hometown · Joined Aug 2008 · Points: 405

Was the haul line static or dynamic?

Chad Hiatt · · Bozeman, Mt · Joined Oct 2015 · Points: 85

I have caught the arm on my micro trax a couple different times and allowed a little slack into the system before it catches.  Even when it's "locked" open, the rope still engages after a few inches in most set ups.  It's very likely that something interfered with the arm, but as Mydans pointed out...speculation.  Short of the sheath slipping, it's highly improbable that anything else could have caused it.

Zach Raney · · Leadville, CO · Joined Aug 2014 · Points: 0

thanks for the ideas. The rope is semi static Unicore. Sheath slippage shouldn’t be an issue. I see a pro traxion in the future...

Mark Hudon · · Lives on the road · Joined Jul 2009 · Points: 415

If you are hauling 1:1 and want to carry a heavier than shit item, the protrac is perfect. 

A CMI pulley with a 2.625 sheave and one of your ascenders (or grigri) s going to be far lighter and more efficient. 

Micro or Mini Trax can sometimes catch on something and not grab, usually it’s user error. 

Hayden robinson · · Unknown Hometown · Joined Mar 2016 · Points: 90

I delt with a slipping pro trax this month on tribal rite. Granted we where dealing with a serious porker, it was two weeks. But the slipping killed me. We where 2:1 hauling so the load never slipped more then a foot or two but it made life hell. I ended up hauling with my finger on the catch bar. Ive been told the kong roll block never has that problem, I'm investing in one as soon as I get the cash 

Mark Hudon · · Lives on the road · Joined Jul 2009 · Points: 415

I’m sure I’ve hauled more pitches with Mini and Mirco Traxs than all of you combined and have never had the problems you guys are describing. 

The cam is staying open on its own? The thing is not twisted and the rope hitting it at an odd angle?

The Kong Block Roll is good if you are hauling Pete Zabrok level bags but far, far too heavy for anything less. 

I always haul 2:1. Sometimes the Zed cord is running quite closely to the Trax and has popped the cam open. That’s user error though. 

kevin deweese · · Oakland, Ca · Joined Jan 2007 · Points: 355
Hayden robinson wrote:

I delt with a slipping pro trax this month on tribal rite. Granted we where dealing with a serious porker, it was two weeks. But the slipping killed me. We where 2:1 hauling so the load never slipped more then a foot or two but it made life hell. I ended up hauling with my finger on the catch bar. Ive been told the kong roll block never has that problem, I'm investing in one as soon as I get the cash 

Block Roll has shown similar problems with slick or fat ropes. I've had 12m static line slip through it like OP is describing. I've also had this issue show up with the microtrax (my progress capture for my 2:1) but only with the glassy 12mm static line we use.

I agree with Mark. Kong's Block Roll is overkill unless you're bigwall camping like Pete or bigwall sieging like me. Seriously, once you're on a 2:1 it's the same weight as the Kong and half the effort.

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346

If the cam is correctly engaged on the rope, I dont see how it could slip without damaging the rope. The teeth physically dig into the sheath when they are loaded and if the rope were to pass through the pulley while the cam was engaged, the teeth will rip the sheath off the rope or at the minimum completely rip it to shreds trying to stop the rope. I've seen that happen several times. If the combination pulley is not catching, my guess is something is preventing the cam from engaging. This could be several things, but probably the most common would be misalignment of the rope with the pulley sheave, physical obstructions stopping the cam from moving (e.g. a sling jamed in it or the cam pressing against the rock), or an extremely dirty cam that is not moving freely.


Also, huge pulleys dont really provide much advantage over smaller ones for a 1:1 haul unless you're using really thick, inflexible ropes. According to Petzl, the micro is 91% efficient and the pro is 95%. If you're 170 lbs with a 1:1 that's only a difference of 7 lbs which wont really mean anything on a counterbalance haul. If your rope is extremely thick and inflexible, a huge sheave will help, but for most of the ropes we use the difference between a 2" and 3" sheave on a 1:1 is going to be zilch.

Mark Hudon · · Lives on the road · Joined Jul 2009 · Points: 415

Good info on the sheave size, 20kn. Thanks for that.  

Hayden robinson · · Unknown Hometown · Joined Mar 2016 · Points: 90

When our pro trax was slipping it was with Pete style pigs, it was a two week party wall. But The capture bar was also pretty damn dirty, I had never had a pully slip like that before, I bet some cam lube or something would of stoped it. 

Hayden robinson · · Unknown Hometown · Joined Mar 2016 · Points: 90

Is it safe to haul pig at least 400 pounds on a micro? I'm just wondering because I wanted to switch to the micro because of the slippage on the pro but we agreed that seemed to sketch with the massive weight of our load 

Mark Hudon · · Lives on the road · Joined Jul 2009 · Points: 415

Come on, Hayden! You just spent two weeks on a party wall. I’m sure you can figure out for yourself if a Micro can hold 400 pounds. 


FIGURE IT OUT! (See my 2:1 In your Brain post)

20 kN · · Unknown Hometown · Joined Feb 2009 · Points: 1,346
Hayden robinson wrote:

Is it safe to haul pig at least 400 pounds on a micro? I'm just wondering because I wanted to switch to the micro because of the slippage on the pro but we agreed that seemed to sketch with the massive weight of our load 

That's what Petzl says. I'd use something larger for that much weight. As the mechanical systems become more complex (beyond 1:1), the efficiency of the pulley will start to matter progressively more.

Guideline #1: Don't be a jerk.

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