Rigging Q. Suprise pit.

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Rigging Q. Suprise pit.

Postby Chads93GT » Jul 6, 2012 3:30 pm

Over the weekend I went to suprise pit and was told the main way to rig was to backup to the boulder 50' away with the arch. And to clip 4 or 5 biners into the 5 anchors at the lip and either tie a fig 8 through all of them or a double 8 through half and half.

Problem is. Doing this creates two American death triangles. What is the problem with rigging to twos bolts with a double 8 or a double bowline?

I inevitably did what I was told and it only donned on me later about the death triangles. Next time I think I'll stick with a double bowline and maybe backup again with another double bowline or 8.

Thoughts? Anyone know how long those bolts are?
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Re: Rigging Q. Suprise pit.

Postby Scott McCrea » Jul 6, 2012 5:10 pm

The first time I went, we did what you did. The next time, when I led the trip, we used two bolts and a double 8 with the tail running back to another bolt for a traverse (get to the bolts safely) line.
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Re: Rigging Q. Suprise pit.

Postby Jeff Bartlett » Jul 6, 2012 6:36 pm

Do you have a photo? I'm not sure how you were able to build ONE American death triangle, let alone two. But I've never been to Surprise or rigged it. Just trying to envision this.

Edit: Oh, just saw a photo on Barry's Facebook -- you probably want to post that here just so other folks can see what you mean. Yeah, those are death triangles! I honestly wouldn't worry about tandem climbing on a double-figure-eight (bunny ear); what I would probably do is put a bunny ear knot on the two nearest the lip (assuming those are solid) and use butterfly knots to add in any extra bolts you'd like to use for backups.
"Although it pains me to say it, in this case Jeff is right. Plan accordingly." --Andy Armstrong
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Re: Rigging Q. Suprise pit.

Postby chh » Jul 6, 2012 8:47 pm

I'm assuming you have that many bolts because some of them (you don't know which) are suspect?
I would probably go with one of 3 options upon inspection of the bolts. Chose 2 to rig and have a back up like Scott said. Find a piece of webbing and make a load sharing anchor on all of them if they are all sh!t. Or, if I can't tell, just clove hitch them all in a series making sure there's no slack between hitches.
I guess there's a fourth option. Go home. But that's not much fun, is it?
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Re: Rigging Q. Suprise pit.

Postby Chads93GT » Jul 6, 2012 10:32 pm

here is the rig at surprise.

The left triangle is the one with the most directional stress. The back one didnt bother me as much but I go bakc I wont do this again. Jeff, I thought about this today at work and i think I would do nexst time what you said. Like at the Warm Up pit in ellisons, I would do a double 8 backed up by a butterfly knot. Rigging all the way back to the boulder 50' away was a hinder but we had 656' of rope to work with and it allowed me not to put all of that rope in the hole.

A friend of mine suggested this. Tie the long bunny ears, and adjust each line the length you need it and clove hitch the back side of it with a biner, just like a pull down rig. This would allow you to equalize the load on all 4 anchors without having a death triangle, but..........this would mean 8 biners to rig. Or tie a double 8, really long, then tie two 8's on each tail to each bolt, but that would be getting a bit riduclous. the bolts did look bomber, they were something like 5/8" diameter bolts or bigger.

It was a blast, the hike was a bit of a pain due to no SCCI trail markers........... if anyone goes and they want a waypoint route for gps let me know, as following the directions is kind of hard. I spent 10 minutes on the phone with the property manager on the hike up. Its just a transition from the road following the river, up the hill till you intersect a logging road that is the iffy part. AFter you hit the logging road its pretty easy.

Anyway, here is the picture.

Image
Image
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Re: Rigging Q. Suprise pit.

Postby Scott McCrea » Jul 7, 2012 6:45 am

Yea, the hike sucks. Especially this time of year--hot and overgrown.

For some reason, your rigging didn't result in instant ('merican) death. You could also use a bowline with a bite (not a bowline on a bite), which can give you three loops/bunny ears.
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Re: Rigging Q. Suprise pit.

Postby Chads93GT » Jul 7, 2012 12:02 pm

Scott. I know how to tie a triple figure 8. I know how to tie a double bowline on
A bite to get two bunny ears (less rope and a lot easier to adjust). But a three loop bowline?

Also. Is the triple 8 really used that much? I figured it was sort of like a self equalizing double 8 where it's frowned upon due to the readjustment that would take place IF an anchor would blow out.
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Re: Rigging Q. Suprise pit.

Postby knudeNoggin » Jul 8, 2012 11:07 pm

These bowlines on / with a bight [<- not 'bite'] are not all so secure
if the eyes are loaded separately : if the eye that the mainline feeds
material into (i.e., coming out of the central nipping turn) is not
loaded --its anchor fails--, there's a fair chance that the material
will slip until that unloaded eye is collapsed --nylon turning around
nylon (think *heat*).
(Chads93GT, the triple-eye bowline results from first "doubling"
the rope (making a long bight), and then tying a *bowline* in
the doubled material : you get the doubled (normal) eye, and
the tail being the bight tip of the material can be used itself
as an eye, the 3rd.)

If the tail of the knot(s) are tied off into the mainline to make
it a bowline with a long eye in which the multi-eye bowline is
then tied, that will be better.

As for the "American Death Triangle", it could be instructive to see
what actual forces are generated by normal use. I surmise that in
this case (of the OP), at least, there is nothing to be concerned with.

*kN*
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Re: Rigging Q. Suprise pit.

Postby Tim White » Jul 9, 2012 9:32 am

Chads93GT wrote:Anyone know how long those bolts are?


Long. 6 - 8 inches. Don't remember exactly. :roll:
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Re: Rigging Q. Suprise pit.

Postby dutchcontractor » Jul 18, 2012 9:21 pm

4 bolts? How bad is the rock? Personally I would just build a (locked) equalized anchor with a short length of cordage. 3 bolts should be more than enough. 4 is just gravy. Thanks for the pictures, now I am prepared for our fall trip.
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Re: Rigging Q. Suprise pit.

Postby Chads93GT » Jul 18, 2012 9:31 pm

So you would use 8mm cord looped through three anchors and made into three loops. The. Tie a figure 8 at the end to secure them all together then clip your rope into that?
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Re: Rigging Q. Suprise pit.

Postby Chads93GT » Jul 18, 2012 9:32 pm

The rock is good. The bolts are big. It looks bomber as hell.
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Re: Rigging Q. Suprise pit.

Postby dutchcontractor » Jul 18, 2012 9:55 pm

Chads93GT wrote:So you would use 8mm cord looped through three anchors and made into three loops. The. Tie a figure 8 at the end to secure them all together then clip your rope into that?


Yup, I realize this adds an extra "link" in the chain, but you'll end up with a simple perfectly equalized anchor. I prefer direct rigging but when it gets too complicated I'll go with the extra link (I use 2 biners). Should be good to take 20+kN. See the picture below.



Image
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Re: Rigging Q. Suprise pit.

Postby Chads93GT » Jul 18, 2012 11:03 pm

I've tied that before. Figured that's what you meant.
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Re: Rigging Q. Suprise pit.

Postby Jeff Bartlett » Jul 18, 2012 11:10 pm

dutchcontractor wrote:Yup, I realize this adds an extra "link" in the chain, but you'll end up with a simple perfectly equalized anchor. I prefer direct rigging but when it gets too complicated I'll go with the extra link (I use 2 biners). Should be good to take 20+kN. See the picture below.
Image


I'm going to ask this question not to be critical, but because I think it's a good question to ask (and this might even be best as another thread): Why?
More clearly stated: why would this be preferable to, say, a double-figure-eight (bunny ear knot) properly stressed-and-dressed in 11mm PMI and connected to two good bolts?
"Although it pains me to say it, in this case Jeff is right. Plan accordingly." --Andy Armstrong
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