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Jumat, 06 Februari 2009

Tyrolean Traverse

Tyrolean Traverse On Lost Arrow SpireContributed to Chockstone by Phil Box.

(Neither Phil, nor Chockstone takes any responsibility for the accuracy of this article, or it's suitability for the purpose. Use at your own risk. Chockstone Photography | Landscape Photography Australia | Australian Landscape Photography

Please read the full disclaimer).

Okay we're going to talk about a simple Tyrolean traverse in terms of what it means to a climber and using the gear that a climber would ordinarily have at hand assuming that said climber has the basics of self rescue gear.

For clarity's sake lets call me the narrator and then we have climber A and climber B. We will be starting from this side, East, and going over to the other side of the chasm to the west and then back across the void to this side, East again.

Right: Tyrolean Traverse from Lost Arrow Spire. Photo by Marten Blumen.

You want to climb a pillar that you don't want to abseil and have to then climb that steep scree slope, solution, Tyrolean traverse. You will need to attach a rope to a dirty great anchor before you leave down the scree slope on the East side. This is best achieved with a no knot or friction knot; three wraps around a giant tree and then institute a figure of eight on the bight at the end of the rope and clip the end of the rope to the main line. Voila we now have the strongest knot known to man i.e. there is no appreciable decline in the rope strength using this knot.Climbers rap into the chasm and lead up the other side.

We will have the other end of the rope attached to us at all times now. You may as well rap using this rope seeing as it's there and all. So be off with you down the slope then, there you go (climber A). Off goes the second (climber B) to join our leader at the bottom. There do you see him on belay, don't they make a picture? Up the other side he goes (pictured left), whoa, watch him he nearly took a whipper. Dude, the hand goes in the crack, damn face climbing Victorians. Oh yeah, ahem, where were we? There goes the second to join our leader at the top of the pinnacle (Over on the west side).

Left: Climbers rap into the chasm down the East side and lead up the other, West side.

So now we've got two climbers on the other side (West) of a chasm with a rope tied to a bomber anchor on this side (East) of the maw. Our leader (climber A) will now tie the rope to another bomber anchor (West side). He can use a traditionally built trad anchor for the time being. Into this anchor he will have two locking biners that the Tyrolean line will be placed using a muenter mule knot. He will now build a haul system utilizing a z drag. The Tyrolean line will now be tightened.

It's actually better to not tighten the line too much but you need to tighten sufficiently so that you don't have too much slack otherwise you'll end up at the bottom of the chasm due to rope stretch. Tighten too much and you'll place undue pressure on the anchor due to the torque multiplying effect. Remember your angles for effective anchor building, if you go over 120 degrees you will be adding strain on each anchor in multiples of force greater than the force that you are applying at the single point, thus on a Tyrolean traverse you may only weigh say 80 kgs but the force on each anchor may be many multiples of that, we're talking huge numbers here. Therefore if you have zero sag in your line you could conceivably either pull that tree out or break the rope. Give the rope a bit of sag and don't stretch it too tight.

The reason for the z drag and the muenter mule is that you can pull sag out of the rope and then shuffle the loose section of rope through the muenter and repeat as necessary to achieve the desired tightness in the rope. The Muenter mule is a way of tying off a muenter hitch.Climber B traverses back to the East Side.

Send the lightest climber back across to the East side first (Climber B). He should be clipped in by his belay loop and a biner and as well he should have jumars to pull himself up from the apogee of his descent. If I might explain a little more, the first back across will of course create some sag in the rope due to his weight he will enjoy a glide downwards until he gets to about midway from there it is all uphill.

Right: Climber B (the lightest) tyrolean traverses back to the East Side first.




The first back across can also be belayed down to the midpoint and then make his own way by way of jumars up from midway point. The advantage of another rope on the first back across will become apparent when we see the necessity to retrieve everything from atop the pinnacle (West).

So now we have one climber on this side (East) and one climber on tuther (insert Yorkshire pommy gardener accent here) side (West). Climber A on other side (West) now has to attach the two ropes together using either an overhand knot or triple fisherman's knots. He will do this before releasing any tension from the system. He will release the muenter mule but not release the z drag. He will also have been searching for a convenient bomber natural anchor that he can run the rope around before he joins the two ends together.

Heh heh look at him running around in circles looking for a dirty great tree that isn't there. He'll just have to settle for slinging the rope around that giant boulder perched precariously (nah it's bomber) on top of the pile. Okay he's got his anchor sorted so now it's over to the climber B on this side of the gulch. Hey buddy, enjoy the ride. Down to the bidness bro, guess what, hope you were paying attention over there on the west side cos you've gotta do exactly the same thing over here dude, that's right tension the other rope you just brought over. Run that rope around that giant tree (on the East side) just like the other one (also on the East side) and then set up a z drag to pull some tension into the rope. There ya go just pull it up just like the other one dude, you've done this before why am I even telling you this? So now on this side (East side) we have two ends of rope running around the tree using no knots and figure of eights on the bight clipped to the main lines.
Climber A also traverses back to the East side.
Climber A on other side (West side) can now release his z drag. As climber A is attaching himself to the traverse he will have two ropes to choose from. He can be attached to one and use the other one as a back up. The best rope to attach himself to is the rope that does not have the joining knot in it as it will be on the other side of the giant boulder. The strand or line with the knot in it will be slightly less strong than that without if you get my drift. Obviously our second traverser (climber A) will repeat exactly the manoeuvres that the first went through to cross the void.

Left: Climber A also tyrolean traverses back to the East side.

So now we have our two heroes back over on this side (East) and they can now simply retrieve their rope by pulling it from this side as it is simply run around the natural anchor on the other side (West) of the chasm. Obviously they will pull the strand with the knot on this side of the boulder so that the knot does not have to be pulled all the way around the boulder. Imagine it as just like having to pull a rap rope that has a knot in it through an anchor, you would pull the knot side down and not the free side down as it is obvious that you cannot pull a knot through an anchor can you?


In Summary
Push For The Summit

To make the concept really simple, a rope is dragged across from the East side then a second rope is joined to the first on the West side and the second rope is dragged back across to the East side so that we now have two ropes spanning a void. There will be a knot where the two ropes are joined. This knot will be set up something like how you would set up a knot for a twin rope abseil. You do not want this knot halfway down the abseil nor do you want this knot halfway across the tyrolean traverse. You will have to do a bit of tensioning of these ropes across the void and to do that you will need anchor knots that are easy to adjust but are absolutely bomber under load and as close to 100 percent rope strength. You will also need to be proficient at z drag hauling to be able to achieve the desired rope tension. You will need to be able to set bomber anchors from which to do your hauling and tensioning.

The thing that really needs stressing is that you will be placing a lot of faith in the anchors you will be using so make sure they are good ones. Another thing that bears mentioning is that when you are at the bottom of the traverse and are ready to come up the other side you will need to prevent yourself from sliding back down the rope as you make your way up. This is very much like a sort of sideways jug so you will be needing 2 prussiks or 2 jumars. Mate it can be hard work particularly if you have a pack to haul. Don't wear it on your back. Suspend it from the biner attached to the rope. It might even be suggested to wear a chest harness to keep yourself from inverting as you grow tired.

Do we need to go through all the disclaimers again, ya orta know it all off by heart by now and of course all climbers know that they take responsibility for their own actions. Climbers generally are the sort of people who know how to assess risk and would never do anything to jeopardise their own or their partners safety so obviously if you are going to take any of this advice then you will of course try this all out in a completely risk free and safe environment and test, test, test and then do a bit more research to confirm in your own mind that the system works.


Use Of Pulleys Push For The Summit

A word of caution when using a pulley in a tyrloean traverse. You should definitely use two pulleys or a double inline pulley which is meant for aerial cableways. The use of a single pulley has resulted in deaths when a load shift happens and the sheave of the pulley is overloaded and it can be twisted off the axle. Two pulleys or the double inline pulley have the necessary redundancy and resistance to the twisting load. The large knot passing Kootenay pulley from Petzl or similar design pulleys from other manufacturers are fine. If you have no alternative to using a small pulley then do use a screwgate biner backup independent of the pulley.


The "No Knot" Push For The Summit

No Knot for tying off a treeI'm referring to the "no knot" as the friction knot. What you do is take the end of the rope and throw it around a tree three times. The tail of the rope you place a figure of eight on the bight and clip that to the main line which of course is the other tail of the rope that you sent three times round the tree. Really this is almost too simple a concept and should not be overcomplicated. We teach the strength and simplicity of this knot by demonstrating how effective simply running the rope around a tree and trying to pull it, it won't undo, the figure of eight on the bight is simply there to ensure that the wraps won't work their way around the tree during the load/unload cycles of rapping.



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Alpine Butterfly

The Alpine Butterfly is a midline knot sometimes used to tie in the middle man during glacier travel. It has found a use, instead of a clove hitch, when equalising anchors for a top rope set up (in specific circumstances). Also sometimes used in Tyrolean traverses. It's easier to untie, after being weighted, than a figure eight and uses less rope. Follow these steps to tie the Alpine Butterfly:




Hey, I resemble that remark!

Step 1Step 2
Step 1: Form a loop in the rope. Step 2: Twist the loop, so that it becomes two loops as shown above.
Step 3Step 4
Step 3: Grab the top of the upper loop and fold it underneath the line. Step 4: Continue the wrap, feeding it back through original loop.
Step 5
Step 5: Pull tight and clip your load to the protruding loop.


Reader's Feedback Push For The Summit

"...The best way [ to tie an Apline Butterfly ] is to simply coil the rope around your hand so that there are three strands on your upturned hand. You then take the coil closest to your fingers and take it back towards your wrist. You then take the coil which is now closest to your fingers and take it towards your wrist except this time you will feed this coil underneath and through the coils which are left on your upturned hand. You will then have a bight of rope protruding through these coils and it will be pointing towards your fingers. Take hold of the bight in your teeth and pull the two ends of the rope that are coming in towards the knot. Voila, you now have a simple to tie Alpine Butterfly. This way of tying is way less able to be stuffed up than that which is illustrated. It's also much easier to accomplish". - Phil Box.

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Girth Hitch ("Lark's Foot")

The Girth Hitch, also known as the Lark's Foot, is useful for tying a sling to your harness. It's probably the simplest knot you can form with a sling, and this is perhaps why it is so popular. It has many other potential applications (such as extending a runner, joining two slings together, etc), however, be warned: the knot will reduce the strength of the sling.

Girth Hitch (Click To Enlarge)There is debate among climbers as to how significant is this reduction in strength, and whether the alternatives, such as joining two slings with a carabiner, are indeed much better. It is accepted that using a Girth Hitch to join two slings is weaker than joining with a carabiner, however using the carabiner you've got other issues such as carabiner cross loading, loading over an edge, etc. Plus the fact that it takes away one more precious locking carabiner from your rack. Never-the-less, almost all resources I've read do NOT recommend joining two slings with a Girth Hitch. The only approved application seems to be tying a sling to your harness.

Above Right: This picture shows two slings joined with a Girth Hitch. This is NOT recommended. Use a locking carabiner to join slings.

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Kamis, 29 Januari 2009

Stopper Knot

The stopper knot is very handy in several situations. For instance you could tie one in the end of the rope it stop it unexpectedly passing through the belay/abseil device. Use it to backup your figure eight follow through tie in knot. Two stopper knots are used to make the double fishermans for joining two ropes.

To tie a stopper knot in the end of the rope, follow these steps.
Step 1Step 2
Step 1: Form a loop. Step 2: Form a second loop behind the first one, as shown.
Step 3
Step 3: Pass the end back through both loops.
Step 4: Stopper Knot

Step 4: Pull tight.

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Garda Hitch ("Alpine Clutch")

Also known as the "Alpine Clutch", this knot locks the rope so it can only move in one direction. It can be used, for example, (in combination with other knots), to ascend the rope or as part of a pulley system for hauling loads. If done correctly it works well, however, I'm not a big fan of this knot and have never used it in a real life situation. If the knot really locks up you might need to prise it free with a nut tool. Also when experimenting with it, I've had one carabiner unclip itself. Note, oval carabiners are recommend, not those shown in the pictures below. I suggest you backup whatever you're doing with it. Judge for yourself if it is a valid option for your application. Follow these steps to tie the Garda Hitch:

Step 1 (Click To Enlarge)Step 2 (Click To Enlarge)Step 3 (Click To Enlarge)
Step 4 (Click To Enlarge)Step 5 (Click To Enlarge)
Step 1: Clip two carabiners, gates reversed, but spines aligned as pictured. Note it is recommend that you use oval carabiners rather than those pictured. Steps 2 & 3: Clip the rope through both carabiners from left to right, and form a loop with the right side tail. Step 4: Clip the loop through the left hand carabiner as pictured. Step 5: Pull tight and apply load. The knot is supposed to slip down the carabiner's spines a little. I suggest having some for of backup rather than relying totally on this knot.


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Jumat, 23 Januari 2009

Mariner's Knot

This knot has the advantage of being releasable underload. Something that can come in handy for rescue work, among other things. The knot looks scary, but is safe provided you clip both protruding tails. The knot will slip a bit when weighted. Ideally the knot should not be used unweighted. Follow these steps to tie a Mariner's knot:

Step 1 (Click To Enlarge)Step 2 (Click To Enlarge)Step 3 (Click To Enlarge)
Step 1: Wrap a loop of accessory cord (or webbing), around an anchored carabiner. Step 2: Wrap the appropriate end of the cord around the other end four or so times, forming the knot as pictured. On the last wrap feed the cord through the remaining loop, leaving it protruding somewhat. Clip a quickdraw (or similar), from the protruding tail to your anchor - this is your backup in case the knot slips too much and fails. Then clip your load to the other end.


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Slip Knot

The slip knot is handy because, as it's name suggests, you can slide it up to adjust the size of the loop. You might use it to sling a horn ("chicken head") of rock for example. Follow these steps to tie a slip knot using a sling:

Step 1 (Click To Enlarge)Step 2 (Click To Enlarge)Step 3 (Click To Enlarge)
Step 1: Form a loop in the sling. Step 2: Feed a second loop through the first. Step 3: Work the knot tight and upwards as required until its snug against the thing you are tying off.



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Munter Hitch

This knot is useful for both abseiling and belaying. It's advisable to use a pear-shaped locking carabiner, and try to avoid cross-loading it. The knot will "flip" as opposite strands of the rope are pulled, this is normal. To lock the knot, apply the braking hand by moving the slack line parrel with the loaded line. See pictures below:

(Click To Enlarge)(Click To Enlarge)(Click To Enlarge)
Figure A: Here you're feeding out slack when belaying, or you're abseiling down. Figure B: To lock the Munter Hitch draw your brake hand up parallel with the load line. Figure C: The knot will correctly "flip" into this position as you take in slack when belaying.



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Clove Hitch

This knot is useful in belay set ups among other things, because it's fairly easy to adjust, unlike, for example a figure eight. With a bit of practise it can be tied one handed. Follow these steps:

Step 1 (Click To Enlarge)Step 2 (Click To Enlarge)Step 3 (Click To Enlarge)
Step 4 (Click To Enlarge)Step 5 (Click To Enlarge)
Step 1: Form a loop in the rope. Step 2: Form a second loop in the opposite direction to the first. Click the image above for a closer look. Some people do this by crossing their hands over (like an X), grabbing the rope in each hand and then drawing two loops whilst uncrossing hands again. Step 3: Place the second loop over the first. Step 4: Clip a carabiner through the loops. Step 5: Pull tight.

sumber : http://www.chockstone.org/TechTips/CloveHitch.htm
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Friction Knots

The Prusik Knot
The good old prusik knot is very, very useful. All you need is a loop of cord which you can make using 6 or 7mm accessory cord and a double fisherman's knot. With one or two prusiks you can ascend a rope, or rig a z-pulley to haul up an injured climber, or backup an abseil. Suffice it to say it's worth learning this gem of a knot. There are numerous variations on the prusik such as the "autoblock", but follow these steps to tie the standard prusik knot:
Step 1 (Click To Enlarge)Step 2 (Click To Enlarge)Step 3 (Click To Enlarge)
Step 4 (Click To Enlarge)Step 5 (Click To Enlarge)Step 6 (Click To Enlarge)
As you can see you simply wrap the loop of cord around the rope going through the inside of each previous wrap. The more wraps the "grippier" the knot. Three wraps is generally enough. Step 6: Pull the knot tight, neaten up the wraps and use the tail loop to clip into. Leaving the knot a little loose it can be slid up and down the rope. Weight the knot and it will grab the rope and lock off. Note: this form of prusik knot can sometimes be difficult to loosen once it has been tightened by the weight of a climber.


The "Klemheist" and "AutoBlock" Knot
The difference with the Klemheist (also called "Machard", or "French Prusik") compared to the normal Prusik is that it can be moved once weighted and will work with webbing as well as cord. This can be very handy in certain situations. Follow these steps to tie a Klemheist:
Step 1 (Click To Enlarge)Klemheist (Click To Enlarge)
Step 1: Simply wrap a loop of cord around the rope several times. Step 2: Feed the bottom tail through the top tail and clip bottom tail with your load.

The "Autoblock" is essentially the same knot as the Klemheist, except that in the last step you simply clip both tails together with a carabiner, rather than feeding one through the other.


The Bachman Knot
This knot makes use of a carabiner as a handle to ease shifting the knot up and down the rope. Note if you pull down on the carabiner, it will unlock the knot, moving it downwards. Likewise yank the carabiner upwards to shift it in that direction. This knot is not so good on icy ropes. Follow these steps to tie a Bachman knot:

Step 1 (Click To Enlarge)
Step 2 (Click To Enlarge)Bachman (Click To Enlarge)
Steps 1 & 2: Clip your loop of cord through a carabiner and begin wrapping the cord around the rope, feeding it through the carabiner with each pass. Keep the wraps nice and snug. Step 3: Allow the tail of the cord to hang down (as pictured), and clip your load to this protruding tail. Do not clip your load to the carabiner functioning as the "handle".


One Method Of Racking Your Accessory Cord
Here's one way to rack your prusik cords so that they have a small profile on your harness gear loops. Simply twist the cord about it self. Follow theses steps:
Step 1 (Click To Enlarge)Step 2 (Click To Enlarge)Step 3 (Click To Enlarge)
When you need to deploy the cord, a quick shake will work out the kinks.

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