|
alpnclmbr1
Jul 7, 2004, 8:18 PM
Post #26 of 42
(3624 views)
Shortcut
Registered: Dec 10, 2002
Posts: 3060
|
In reply to: This method of using two overhand knots at each end, with the webbing looped around a block or tree (a slip knot of sorts?) seems to be very common with the group that I climb with. I'm not wedded to that concept and would like to know how you would do it otherwise.
Webbing on webbing slip knots are a bad idea in general.
I pretty much never use single strand webbing with end knots.(not much reason to)
In reply to: Oh yeah, if you are going to keep on with loops in single webbing, you could learn the trick where you clove hitch to a tree ( or wrap many times I've heard) and then tie a loop knot in the tail and biner the loop to the strand that goes to the anchor. I forget the name of this.
Tensionless hitch.
|
|
|
|
|
dutyje
Jul 7, 2004, 8:30 PM
Post #27 of 42
(3624 views)
Shortcut
Registered: Apr 1, 2004
Posts: 727
|
Reading the long list of replies in yet another anchor thread (thanks, sync. I appreciate you stepping up to the plate here), something occurred to me that you enlightened old fart traddies could maybe help me out with:
I know it isn't the case on this anchor, but I've seen it mentioned in other anchoring threads:
"If you're worried that the giant block there isn't quite secure enough, stick a cam somewhere to back it up, and equalize the whole deal with a cordalette."
Now, as I've admitted in other threads, I own no trad gear, and am but a lowly top-roper. But I've heard this logic applied to top rope anchors quite a bit.
If that giant block should teeter and fall, I have a hard time imagining any single bomber cam placement is going to keep said block from tumbling down the face of the cliff onto my head. Envisioning a scenario where the webbing and biners held, I've now got a single point of protection trying to suspend me and a gigantic mass of rock in the air.
What did I miss here? Even if this block isn't directly equalized with my one remaining piece, it's going to fall off the cliff , travel down the rope (because it's clipped into that rope) and sweep me right down to my belayer, where we will both be flattened into pancakes. Ouch.
All that said, I wonder how many incidents there are, from year to year, of gigantic boulders being swept off the top of cliffs by top ropers taking little 0-3 footers.
Sorry for the ramble. It's a direct result of my n00bidity.
|
|
|
|
|
alpnclmbr1
Jul 7, 2004, 8:33 PM
Post #28 of 42
(3624 views)
Shortcut
Registered: Dec 10, 2002
Posts: 3060
|
In reply to: "If you're worried that the giant block there isn't quite secure enough, stick a cam somewhere to back it up, and equalize the whole deal with a cordalette." Now, as I've admitted in other threads, I own no trad gear, and am but a lowly top-roper. But I've heard this logic applied to top rope anchors quite a bit. If that giant block should teeter and fall, I have a hard time imagining any single bomber cam placement is going to keep said block from tumbling down the face of the cliff onto my head. Envisioning a scenario where the webbing and biners held, I've now got a single point of protection trying to suspend me and a gigantic mass of rock in the air. What did I miss here?
Nothing.
Don't anchor to large questionable blocks. If you feel a need to equalize top rope forces in order to make the block adequate, then the block shouldn't be used.
This same scenario applies to multiple tree anchors, with the exception of sometimes it is best two have two lines going to a TR powerpoint in order to stabilize side to side movement.
|
|
|
|
|
|
|
|
kindredhawk
Jul 7, 2004, 8:48 PM
Post #30 of 42
(3624 views)
Shortcut
Registered: Jan 19, 2004
Posts: 61
|
friction knott/hitch
|
|
|
|
|
alpnclmbr1
Jul 7, 2004, 8:56 PM
Post #31 of 42
(3624 views)
Shortcut
Registered: Dec 10, 2002
Posts: 3060
|
That's it. The reason they use a biner is the same as the reason below.
In reply to: And what is your main concern with the single webbing strand slip knot?
"Slip" and webbing or webbing on webbing are a generally a bad combination due to the possibility of melting. (a girth hitch won't usually slip)
20 feet of webbing cost $3 more then 10 feet.
Single webbing is technically strong enough, but if I can have twice as strong(and twice the abrasion resistence) for $3 more, then why not?
How strong is an overhand knot on a bight in webbing? I don't know because I never use one. Do you?
|
|
|
|
|
kindredhawk
Jul 7, 2004, 9:14 PM
Post #32 of 42
(3624 views)
Shortcut
Registered: Jan 19, 2004
Posts: 61
|
hey alpnclimber... why webbing over cord? is it just stronger? i am a big fan of just cord. knots are easier to get out.
|
|
|
|
|
tradklime
Jul 7, 2004, 9:53 PM
Post #33 of 42
(3624 views)
Shortcut
Registered: Aug 2, 2002
Posts: 1235
|
In reply to: "Slip" and webbing or webbing on webbing are a generally a bad combination due to the possibility of melting. (a girth hitch won't usually slip)?
In reply to: How strong is an overhand knot on a bight in webbing? |
|
|
|
|
bighead
Jul 7, 2004, 10:36 PM
Post #34 of 42
(3624 views)
Shortcut
Registered: Apr 15, 2004
Posts: 68
|
In reply to: My partner then found that nut placement, which at the time I thought was iffy - but like I said he felt the two pieces of webbing were so good, he wasn't as concerned with getting the highest quality out of the third piece.
:shock: :shock: :shock:
That could be a famous last quote. Do a search on this site and you will find accident reports where individuals had three pieces they thought were bomber pull. Take the time to do it right because it might be your last chance. If you ever think "it's good enough" then it's probably not.
|
|
|
|
|
alpnclmbr1
Jul 7, 2004, 10:39 PM
Post #35 of 42
(3624 views)
Shortcut
Registered: Dec 10, 2002
Posts: 3060
|
In reply to: hey alpnclimber... why webbing over cord? is it just stronger? i am a big fan of just cord. knots are easier to get out.
Webbing is cheaper and lasts longer. (more abrasion resistance)
I don't really find myself tying or untying very many knots.
I wouldn't use a belay cordelette in a tr anchor unless it was dedicated to that use.
Other than that, it is a matter of personal preference, and what works for you.
|
|
|
|
|
philbox
Moderator
Jul 7, 2004, 10:42 PM
Post #36 of 42
(3624 views)
Shortcut
Registered: Jun 27, 2002
Posts: 13105
|
I too am a great fan of cordage. Webbing in most instances can fail with only a very slight nick. This is as a result of how they are sewn. The are constructed as wide flat lengths of material and then they are folded in half and sewn together. If a nick is developed in the side of these flat sewn webbings then they can unravel at an astonishingly fast rate. Of course there is also mil spec webbing and this webbing does not suffer the same fate as the nylon sewn tube webbing. Spectra on the other hand is very cut resistant and the extremely low friction coefficient allows this webbing to slip across sharp edges with a far lesser potential to cut.
I like big beefy static for top rope setups. The sheath of the rope creates its own inbuilt redundancy as the main strength of rope is in the core and thus if you get a nick in rope this provides an indicator to retire the rope. Webbing on the other hand if it gets a nick may be the first indication of total and catastrophic anchor failure without warning.
I continually counsel people not to use a girth hitch knot when other better and far stronger options are available. This knot reduces the strength of the webbing or cordage by a significant amount over simply using a tensionless hitch or better yet just double the length of the sling and clip both ends into a biner.
|
|
|
|
|
alpnclmbr1
Jul 7, 2004, 10:43 PM
Post #37 of 42
(3624 views)
Shortcut
Registered: Dec 10, 2002
Posts: 3060
|
In reply to: In reply to: "Slip" and webbing or webbing on webbing are a generally a bad combination due to the possibility of melting. (a girth hitch won't usually slip)? With Sync's configuration, once tensioned, is there really much opportunity for slipping?
Strange things can happen, why take the risk?
|
|
|
|
|
tradklime
Jul 8, 2004, 2:21 PM
Post #38 of 42
(3624 views)
Shortcut
Registered: Aug 2, 2002
Posts: 1235
|
In reply to: In reply to: In reply to: "Slip" and webbing or webbing on webbing are a generally a bad combination due to the possibility of melting. (a girth hitch won't usually slip)? With Sync's configuration, once tensioned, is there really much opportunity for slipping? Strange things can happen, why take the risk?
Well I suppose that gets into the larger philosophical question of previous anchor threads...
|
|
|
|
|
sharpie
Jul 8, 2004, 3:05 PM
Post #39 of 42
(3624 views)
Shortcut
Registered: Nov 8, 2002
Posts: 1111
|
Damn Sync, you love anchor threads don't you...
|
|
|
|
|
beesty511
Jul 8, 2004, 3:15 PM
Post #40 of 42
(3624 views)
Shortcut
Registered: Mar 4, 2004
Posts: 336
|
One problem with a tensionless hitch: some people have reported reaching the top of climbs only to find someone has stolen the biner out of their anchor. I wouldn't think that's a common problem, but since there isn't any tension on the biner, anyone that is willing can steal it.
|
|
|
|
|
dirtineye
Jul 8, 2004, 4:10 PM
Post #41 of 42
(3624 views)
Shortcut
Registered: Mar 29, 2003
Posts: 5590
|
In reply to: One problem with a tensionless hitch: some people have reported reaching the top of climbs only to find someone has stolen the biner out of their anchor. I wouldn't think that's a common problem, but since there isn't any tension on the biner, anyone that is willing can steal it.
That's a good reason to start your tensionless with a simple clove hitch.
I've heard a story about some hikers removing some 'trip lines' from a cliff edge trail. They didn't understand that the webbing was part of an anchor that people were climbing on.
|
|
|
|
|
corpse
Jul 8, 2004, 4:14 PM
Post #42 of 42
(3624 views)
Shortcut
Registered: Jan 17, 2003
Posts: 822
|
instead of using the webbing to tie a fig 8 then attach with a biner, why not just attach a double fisherman to the webbing? you aren't expecting the knot to be loaded (if it is, its still strong enuf), and won't be as easy to remove (ie: hiker), plus it saves you a biner.
|
|
|
|
|
|
