Rope crossed

[Treeaddict]

I know many situations where crossed ropes is dangerous (rigging line burning through your climb line) or undesirable (harder to move in MRT) Is the situation depicted in the picture a safety concern in a SRT tree access scenario? The climber is the Prusik. Is the friction between both legs of rope trivial and would take 2 years to abrade?

 

[ruel]

Probably ok but I'd not set it like that myself. Build good habits. Crossing Lines just bug the hell out of me now.

 

[Treeaddict]

I know what you mean. It bothered me enough to get down after 30’ ascent. The abandoned plan was deadwooding at 80’. It was a tight shot 100’ up so I wasn’t anxious to re shoot and work the bag. Happened during working the throw line.

 

[ruel]

I hear that. If I was working and had spent 30 min getting that branch , I'd go up to the TIP (tie in point) and reset it before Working.

 

[Altissimus]

Just skip the half twist , run direct (no possible rub). On Ski Patrol for Rope Lift Evac. we had to put a twist into the line ... (never felt right)

 

[Burnham]

I'd avoid that. But as close to the anchor point as it is, there would be little back and forth friction. The farther away the crossover is from the anchor, the more stretch will allow more movement.

So in the case you describe, I'd probably climb on it straight to that point then rerig, as Sean suggested.

 

[SkwerI]

After climbing DRT for my entire career, mostly natural crotch, I'm well versed in friction on my lifeline. I think you should be more worried about a rabid squirrel chewing through your rope before you worry about the minuscule amount of friction put on your rope in that scenario. Hate to disagree with all you 'better safe than sorry' folks, but nothing in that scenario could ever possibly cause any harm to that rope.

 

[lxskllr]

My thinking's along with the Skwerl's, but I didn't say anything, cause wth do I know? Rope on rope friction is how most of this stuff works, and anything like a *single* tie in won't cause enough damage to matter. A permanent installation of some kind would warrant more concern imo. Having crossed or weird lines would bother my sense of order and neatness, but I wouldn't feel bad about climbing on it, especially if it was a hassle getting it set.

 

[SkwerI]

To rephrase it, if you hung a swing in a tree using the same method, the rope would dry rot due to exposure to the elements before there was any friction damage from the rope rubbing on itself. There would be more wear where the rope went over the fork in the tree.

 

[Treeaddict]

Good stuff guys! Learning much. I’ll ascend and reset. That’s tomorrow’s fun though. But, this situation has me thinking about ropes in regard to friction, melting, and abrasion. Bark may abrade more while rope to rope friction would produce more heat? Rope on rope will not abrade itself but it will produce heat which will melt through the rope?

 

[SkwerI]

Good stuff guys! Learning much. I’ll ascend and reset. That’s tomorrow’s fun though. But, this situation has me thinking about ropes in regard to friction, melting, and abrasion. Bark may abrade more while rope to rope friction would produce more heat? Rope on rope will not abrade itself but it will produce heat which will melt through the rope?

It wasn't too long ago when friction hitches were used instead of mechanical friction devices. Many of us climbed our entire careers using rope on rope friction to control our descents. It takes a LOT of friction to damage a rope. Nothing you do in your climbing system will ever come close.

 

[Bermy]

I agree with both the sentiments here, in the end it comes down to what mental mind games are you willing to put up with.
The crossed rope would bug me, even knowing the chances of it rubbing through during one climb are tiny. So I would fix it if it were early in the job.
S
However, sometimes during a climb my working side has crossed my down leg, I'm aware of it, I'm not keen on it but depending on where I am in the job and where I have to go, I've carried on and it's uncrossed later in the job.
I swear, tree work is a large dash of mental mind games.

 

[SeanKroll]

The downside of SRS/ SRT is that a sharp stub can rub the same spot of rope.