What to do with a second rope?

[kurthicks]

Here's one way to rap on one and pull the other...

 

Click me

[dryad]

That's pretty damn slick! Don't have to rely on wedging a fattie knot in a rap ring or biner. How much would it damage the biner to have it knocking around and falling down when you pull the rope? Somebody must have a link to drop test results bookmarked.

[iain]

yeah that setup wouldn't knock down any rocks and would remain unstuck 100% of the time

[rbw1966]

wazzumountaineer said:

Here's one way to rap on one and pull the other...

 

Click me

 

This was the method I was referring to above. Its worked every time I used it and has never gotten stuck, but of course YMMV. You just have to exercise a reasonable amount of common sense to keep the biner from getting wedged. Remember, it follows your rap line all the way down.

 

Also, to avoid getting the zip line all clustered by the wind you can leave it wadded in your pocket and feed it out as you rap. Its a PITA though.

[Sabertooth]

dryad said:

That's pretty damn slick! Don't have to rely on wedging a fattie knot in a rap ring or biner. How much would it damage the biner to have it knocking around and falling down when you pull the rope? Somebody must have a link to drop test results bookmarked.

 

It's slick until you whack yourself or your partner in the head or shoulder with the biner while pulling the ropes. Also remember to NEVER use that biner again for anything that will take a high fall factor. Tape and label it as a rap guide biner only. It will have microfractures in it and after it smacks into the rock.

[ken4ord]

wazzumountaineer said:

Here's one way to rap on one and pull the other...

 

Click me

 

You can still get the knot stuck in the rap ring or sling in this case. The arrows shown are which direction you pull to retrieve your ropes, not the direction of force when rapping on a single strand. (I am hoping in this scenario that people would choose to rap on the "ok rope".) I don't see the point of the locker. Maybe it's too early and the two brains on the wheel have not gotten up to full speed. I am going to get some coffee and then see if someone can explain to me.

[Rodchester]

I'm not so sure I but into the micro fractures thing. Its been sometime, but years ago I worked in a gear shop, and a BD rep showed the counter jockeys some test data that basically said the micro fracture arguments were just BS.

 

Granted, if a biner takes a full on fall, reaching terminal velocity and slams into rock, I'd be warry and would retire the biner. But too many take this whole thing to the crazy level.

 

One guy came in one day, and said that he thought our biner display was cool, and then chastized us for having it over a concrete floor, because the biners could be dropped (roughly 1ft. to 4ft.) onto the concrete floor causing micro fractures. At this height/impact any biner banging up against rock would be suspect, and we would return to steel biners.

 

I try to stay up on the UIAA reports on ropes and gear and read the AAC info put our yearly. I have yet to see anything that indicates that micro fractures are an actual problem. Maybe I'm wrong... . Admitedly, I am no engineer or test guy. However, if this were such a problem, gear companies would be reminding us at every dropped biner, not just for liability reasons, but so they could get people to buy more gear. There is nothing in BD literature that comes with thiere hardware. Also, where are all of the accidents reports on gear failing because of micro fractures?

 

Anyone know of any reports on the web?

 

If you have old gear that you dropped, send it one to me. Send me a PM and I'll pass on my address info.

[lummox]

I'm not so sure I but into the micro fractures thing.

you need to see the movie cliffhanger. it convinced me not to trust gear. that shit just up and breaks on ya.

[iain]

I agree, you need to be able to point to data to make those claims. Otherwise you get stuff being taught like prusiks need to be wrapped the same direction to climb a rope (true story)

[Rodchester]

Do a Google search for "microfractures carabiners"

 

A real wealth of info........

[Matt_Anderson]

When using a very thin cord (less than 7mm) as your second rope, you don't put it through your belay device, you just rapel on the thick cord. The knot jams against the rap ring/anchor and holds the thick line in place. You rap on the thick cord, then pull on thin cord to get both ropes down. You just have to make sure that the knot is jammed against anchor before weighting it. If the knot is on the wrong side of the anchor, and you weight it, you take the big ride.

 

This seems to increase risk for no good reason. When I rappell on a fat and a skinny cord, I always stick both cords through the device, regardless of how well jammed the knot may be. Here's why:

1) It doesn't make things any more difficult;

2) It gives you a bit more friction (which is generally a nice thing when rappelling on only one line)

3) It decreases the likelihood of the light line getting blown and tangled and ensures that you have a hold of hte line that you need to pull on when you get to the end of the rappell; and

4) If the knot does slip, you aren't dead.

 

That said, two skinny doubles are really nice for long ropes - use those if you can afford them.

 

matt

[Sabertooth]

iain said:

I agree, you need to be able to point to data to make those claims. Otherwise you get stuff being taught like prusiks need to be wrapped the same direction to climb a rope (true story)

 

It is true that there is little to no data or research on this in the climbing industry. However, if you have a backround in Aerospace and especially Materials, you know that microfracture problems are indeed a reality. Critical parts such as the turbopumps in the Space Shuttle's engines and fanblades in jet engines are regularly scanned for this. If they find them, they are retired.

 

It's not a critical thing to catalog which biner has fallen from what height, but I do think it is good practice not to use a biner for lead climbing that has taken a 60 meter fall and slammed into a rock. Research on jet engine fan blade impacts suggests this is indeed a problem. I'll look for a online link.

[Rodchester]

So the lesson is...retire your turbopumps and jet engine fan blades if they take any kind of a fall on rock...

 

Bit of a stretch from Aerospace to rock climbing? I think there are some differences, say the heat? Just to start with?

 

In fact, a very good friend of mine is an Aerospace engineer, we've discussed this a few times (she is a very good climber too) and she tends to agree that it is mostly BS when it comes to climbing. (Again if it is a 60 meter fall on hard rock, I'd take a close look at it).

 

Not trying to be an ass...but show me the fractures...so to speak.

 

[iain]

I can see the mechanism for damage from a 60m fall on rock and would probably retire the biner. What I want to see is a bunch of biners dropped from that height, then drop-tested with a bunch that have not fallen. I don't like the idea of doing something "just because". That's how you wind up with 12mm ropes in rescue, doubled-back plastic buckles, and etc, etc.

[Sabertooth]

Good points guys. It is a stretch for that comparison I guess. I personally have one biner that is labeled just for this purpose and I won't be changing my ways. I'm not interested in testing this argument with my life. Iain, I'd like to see that data as well.

[eternalX]

So what you're saying is, you'll set my country music award on fire?

 

 

[ketch]

I'm not sure I buy into the micro fracture idea either. If the beiner took a free 60 m fall it may sutain damage. In the scene were looking at it's gunna fall at most 30m and that while towin a rope (for most of my raps, it could fall 40-50 if a guy went a pure 60m all overhung). If pullin the rope is even a bit dificult you may even have it in hand before it "falls". Lot softer landing that way.

[Terminal_Gravity]

When RBW suggested the "zip cord' idea; I assumed correctly that he ment a system like the link. I think that is the only reasonable method. The jammed knot should only be used with both ropes through the device. Otherwise the consequenses of failure are too great.

 

As far as a biner droping 60m. I may retire a biner after that but with the above system it will not free fall all that way. It won't start falling until the rope pulls through and even then it will be slowed by the rope falling. I really think it is a non issue. When I have used this method the biner doesn't do any worse than bang lightly on the rock...Ussually you can catch it or the rope near it.

 

Also, a figure 8 is an acceptable rope connection for rappeling; as long as the two ropes come out of different sides of the knot and you over hand the ends. If you tie it as on a bite, the knot can capsize and kill you. The above being said I only use that knot for rappeling on slabs and only because the scraping of the knot on the rock when pulling wears the sheath less than on a double fishermans. On a steep or overhung rap the D-fishermans is easier to untie.

 

The above posts on the falling biner question reeks of a bunch of opinions from bored climbers that don't really have any experience to back it up. no offense intended, but don't give opinions when you don't have a clue what the real situation is

[Terminal_Gravity]

Oh yeah, the original question. If they are both fat, single ropes, it is much less work and hassel (on anything but a single pitch route that you plan to rap back down ) to leave the rap rope in your pack or on your back.

[Stephen_Ramsey]

TG,

 

You mean, sort of like a "rewoven figure 8", only with the two strands going in opposing directions ? Just wanting to make sure I understand this. I'm clear on the point that you don't want to use a figure-8 on a bight to connect two ropes for a rappel. Just wondering how to tie the two ropes together correctly using a figure-8. (For now, I'll just use the EDK until I can get a clue on this figure-8 technique).

 

Cheers,

Steve

Edited August 15, 2003 by Stephen_Ramsey

[ctuller]

The fig eight knot for rap would look like this. Easy to get stuck tho. The EDK is a better choice.

[Stephen_Ramsey]

ctuller,

 

Thanks.

 

-Steve

[rbw1966]

I am a big proponent of the EDK. Pretty much idiot proof as long as you dress the knot--and you do that anyway right?

 

Chris Harmston, formerly Quality Control directory at BDEL, debunked that whole microfracture theory a couple years ago. If you can't find it by googling it, try googling rec.climbing.

 

As TG pointed out, the biner isn't going to be falling 60 meters so its a non-issue.

[iain]

in a desire to rack up my votes for greatest mountie -

the EDK is an incorrectly-loaded overhand knot. It is very weak and I would not use the EDK for ropes of dramatically different size. I have used the EDK quite often though.

[rbw1966]

Sorry--I should have clarified. WHen joining ropes of EQUAL diameter the EDK is my knot of choice.

 

I agree with Iain and he gets my vote for best mountie