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jcapell
Apr 19, 2010, 10:48 PM
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patmay81
Apr 19, 2010, 10:57 PM
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1. no
2. if you want
3. yes
4. no, neither is a good way to go.
I would say ditch the webbing, do a three wrap around one tree and tie a bowline or clip a fig 8 on a bight back to the pull line. If its not a bft, then wrap the other tree too and pull the rope between the two to a master point (like you already have done). tie a fig 8 on a bight (not the crazy 3 looped fig 8 you've got going either) at this master point and clip 1 or two lockers into that.
(This post was edited by patmay81 on Apr 19, 2010, 10:59 PM)
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dugl33
Apr 19, 2010, 11:09 PM
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Good job, Bub. I'd climb on that rig any day.
1.) Probably wouldn't bother. Perhaps on the red side. Opposite and opposed regular biner is fine.
2.) What would a stopper knot do for you? These are used more when your V goes to two different pieces, and failure of one piece would cause a lot of extension. Do you mean a power point knot to make the webbing redundant?
3.) Triaxial load? Not enough to worry about.
4.) Both wraps are acceptable.
In summary, looks Solid, Equalized, Redundant, No-Extension. The trees are no doubt bomber, and all critical points are redundant. 
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jcapell
Apr 19, 2010, 11:52 PM
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davidnn5
Apr 19, 2010, 11:56 PM
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jcapell wrote: In reply to: (2) ... Do you mean a power point knot to make the webbing redundant? Nah, I was referring to the remaining tail off the fig 8 in the static rope. I asked that question on behalf of one particular climbing partner (hello, Randy) who seems to like seeing a stopper knot tied in anything with a tail. I personally understand it to be unnecessary.
Your understanding is correct. Stopper knots rarely hurt anything, however.
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TarHeelEMT
Apr 20, 2010, 12:14 AM
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jcapell wrote: Larger images available HERE Right leg (the red tied webbing): [image]http://www.capell.net/(temp)/right-leg(small).jpg[/image] Left leg (the blue sewn sling): [image]http://www.capell.net/(temp)/left-leg(small).jpg[/image] Master Point: [image]http://www.capell.net/(temp)/master-point(closeup)(small).jpg[/image] Questions: (1) Is there any reason to use a second locker on either leg? (2) Should I add a stopper knot to the right leg (red webbing)? (3) Does the right leg (red webbing) potentially tri-load the carabiner? (4) Is either sling wrap method shown preferable to the other? Note: Shown before load applied to make for easier visual inspection.
1) No. You've gone well past the standard of "good enough" at that point. The infinitesimally small added safety margin isn't worth the added complexity.
2) No. Webbing doesn't need stopper knots so long as adequate tail is provided and the webbing can be periodically inspected after frequent cycles of loading and reloading. I'm pretty sure John Long recommends against it in Climbing Anchors.
3) No. The angle of the webbing leaving the biner is very acute and in line with the long axis of the carabiner. You're fine. (alternately, yer' gonna die!)
4) Practically? Probably none. With the blue anchor, a girth hitch conceivably increases the load on the webbing because of the obtuse angle created when the hitch pulls the loaded strand away from the direction of loading. It's not likely to be a safety problem here, but it is still something to consider. The advantage of the girth hitch is that it is not likely to ride up on the tree the way the red webbing is. If you have enough webbing to do it, wrapping the webbing once completely around the tree before joining it as in the red webbing will keep it in place without the potential force multiplication of the girth hitch.
In other words, a lot of words to say "probably not" in response to #4.
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dugl33
Apr 20, 2010, 12:21 AM
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jcapell wrote: In reply to: (2) ... Do you mean a power point knot to make the webbing redundant? Nah, I was referring to the remaining tail off the fig 8 in the static rope. I asked that question on behalf of one particular climbing partner (hello, Randy) who seems to like seeing a stopper knot tied in anything with a tail. I personally understand it to be unnecessary.
Oh. I see. Well, I wouldn't bother. You've got like 3 feet of tail going. How on earth is that going to come untied? I think stopper knots on figure eights are more about having an adequate amount of tail on your tie in knot than anything else. Meaning, if you have enough tail left over to tie a stopper knot, you have enough tail, period.
Personally, I frequently tell beginners to not freak out if the stopper knot on their tie-in comes untied while they are climbing, since its not critical.
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bill413
Apr 20, 2010, 12:30 AM
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Looks to me like an excellent anchor. I'd climb on it anyday (of course we're assuming the red & blue slings actually attach to reasonable points).
The way the girth hitch (blue sling) is rigged, there isn't a lot of loading from a pulley effect, so it's not as bad as some. In this application, it's totally fine.
Stopper knot - on a figure eight, you really don't need one. It doesn't hurt, but it's not necessary for this knot. You've got a good long tail.
Triaxial loading - not with that angle - looks fine.
Extra lockers? Not needed - you already have redundancy by having two separate legs.
My one quibble is that it looks like the rope is running against the ground going through the master point biners. If that's correct, extending the master point lower to decrease the friction of the climbing rope on the ground would be good.
Nice job.
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redlude97
Apr 20, 2010, 1:55 AM
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Are those BD vaporlocks being used for a TR anchor? Now THAT is massive overkill
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patto
Apr 20, 2010, 2:55 AM
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redlude97 wrote: Are those BD vaporlocks being used for a TR anchor? Now THAT is massive overkill
How? 
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curt
Apr 20, 2010, 4:27 AM
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patto wrote: redlude97 wrote: Are those BD vaporlocks being used for a TR anchor? Now THAT is massive overkill How?
So, you think carabiner weight is critical in a TR anchor setup?
Curt
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bill413
Apr 20, 2010, 1:37 PM
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dbogardus wrote: dugl33 wrote: In summary, looks Solid, Equalized, Redundant, No-Extension. The trees are no doubt bomber, and all critical points are redundant. How is this anchor redundant? I also wouldn't claim it's equalized without know where the direction of pull is coming from. I would rather have used up all that extra cord you've got to build a standard cordalette rather than having one strand of cord for each arm. That would make the anchor (more) redundant. Having said that, I would climb on that.
Redundant - two independent legs, multiple isolated strands at the master point. No single point of failure.
Trying to use a thick static as a cordellette tends to be difficult and bulky.
And, with only two legs, where would you see an advantage to a cordellette anyway?
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dingus
Apr 20, 2010, 1:55 PM
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dbogardus wrote: dugl33 wrote: In summary, looks Solid, Equalized, Redundant, No-Extension. The trees are no doubt bomber, and all critical points are redundant. How is this anchor redundant? I also wouldn't claim it's equalized without know where the direction of pull is coming from. I would rather have used up all that extra cord you've got to build a standard cordalette rather than having one strand of cord for each arm. That would make the anchor (more) redundant. Having said that, I would climb on that.
How redundant does a top rope anchor need to be? Triple? Quad?
Its a TR anchor.
That rig looks like it would hold a truck.
Climb on.
DMT
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jcapell
Apr 20, 2010, 2:31 PM
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Rudmin
Apr 20, 2010, 3:38 PM
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...So if one of those trees get's uprooted and tumbles over the edge, the other tree is going to catch it?
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dingus
Apr 20, 2010, 3:44 PM
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Tumbling trees, the New Dread!
What is the purpose of trying to equalize two big trees for a top rope anchor, if you all please?
Or are you just applying SRENE willy nilly, as you were taught?
DMT
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viciado
Apr 20, 2010, 3:45 PM
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You mentioned above that you wanted feedback on the BFK.
I have been using it for TR set up recently and have come to appreciate it more than I thought I would.
I like it for the redundancy. Why do I feel that is important? Well, admitedly, it is mostly that I "feel" better having more than one strand on a system that is cyclically loaded even though the loads are relatively small.
I also like it because after repeated falls, it is much easier to untie than the eight. Yes, the 8 is not "that" bad, but in comparisson I have found it easier.
For clients, it also "looks" more solid and thus may help them gain confidence in the equipment.
These arguments are a bit esoteric at best, but they are my honest explanation for using the bfk on tr. I would not use it outside of that application for other reasons that don't enter here.
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johnwesely
Apr 20, 2010, 6:03 PM
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Rudmin wrote: ...So if one of those trees get's uprooted and tumbles over the edge, the other tree is going to catch it?
Like I have always said, If that tree, rock, huge chockstone, etc comes tumbling down my anchor set up is the least of my worries.
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cracklover
Apr 20, 2010, 6:36 PM
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It's way overkill in almost every aspect.
GO
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jbro_135
Apr 20, 2010, 7:47 PM
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The only thing I would change is the girth hitch for the sewn sling, you lose a significant amount of strength that way. The way you have the red sling set up is preferable. Not that that matters in the slightest, you got a bomber anchor brah
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cracklover
Apr 20, 2010, 8:01 PM
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Okay, I'll answer your questions, but then I have some for you.
(1) Is there any reason to use a second locker on either leg?
No.
(2) Should I add a stopper knot to the right leg (red webbing)?
No.
(3) Does the right leg (red webbing) potentially tri-load the carabiner?
No.
(4) Is either sling wrap method shown preferable to the other?
In this particular case, no.
Now four questions for you:
(1) Based on the size of these trees, why ever use more than one? In certain circumstances, there can be good reasons to do so - I'm not just picking on you.
(2) Why do you use a locker on each sling, rather than a non-locking biner.
(3) On the blue leg, why do you have the clove hitch backed up with a fig 8?
(4) At the master point, why do you have three independent loops going to your biners? Why not two? Why not one?
And a bonus question: (5) What does redundancy in a system mean, to you?
GO
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dbogardus
Apr 20, 2010, 8:02 PM
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acorneau wrote: dbogardus wrote: I would rather have used up all that extra cord you've got to build a standard cordalette rather than having one strand of cord for each arm. Really?!? That static rope is good for ~6,000 lbs. single stand. Two strands sharing the load is ~12k. Even accounting for 25% reduction for knots still gives you 9,000 lbs.!!! Gimme a break. 
What's wrong with a faster setup which holds more weight?
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bill413
Apr 20, 2010, 8:12 PM
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cracklover wrote: (4) At the master point, why do you have three independent loops going to your biners? Why not two? Why not one?
If you use a bhk, it's nice to clip that third loop into something - cheap backup. I look at it as akin to clipping the loops of the Munter-Mule when you're tying off a belay.
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