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By skierhs
May 29, 2013

hey, im starting to build a rack and top rope set up for devils lake but i live a tad too far to go scout out what cams i need, i was wondering does anyone had any advice to sizes and gear i should get?


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By jon jugenheimer
From Madison
May 29, 2013
hi

A single set of cams to a #3 BD and a set of wires will get you up most everything. The harder the route gets, the more specialized gear you may want, like ball nuts and really small cams.

TR, get 20 feet of 9mm cord and two lockers and you are set if you will be using rock gear for anchors.


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By DrunkenHaymitch
From Madison, WI
May 29, 2013

^^^ what he said... plus I usually carry a long piece of webbing (30'+) for when I have to tie off a tree really far back or want to sling a really big boulder. Really depends where you are going to TR, some places have ample places to place pro at the top others have turf up to the edge.


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By jon jugenheimer
From Madison
May 29, 2013
hi

Keep in mind, don't girth hitch trees, it kills them slowly over time. A simple non-tightening loop will do to make a tree anchor.


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By Jeff Howard
From Hales Corners WI
May 29, 2013

A non tightening loop will put more force on a smaller area of a given tree and if repeated over time cause more damage then a girth hitch that is rigged with a slight return.


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By jon jugenheimer
From Madison
May 29, 2013
hi

I always thought the tightening nature of the girth hitch was the worst of two evils. And that's how the trees on top of shovel point in MN died.

As for "more force", I would like to know the math before I can agree with that statement.


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By Carl Sherven
May 29, 2013

jon jugenheimer wrote:
I always thought the tightening nature of the girth hitch was the worst of two evils. And that's how the trees on top of shovel point in MN died. As for "more force", I would like to know the math before I can agree with that statement.


If you look at a simplified free-body diagram a girth hitch acts like a pulley system.

If you assume all friction is between the webbing and the tree (no friction where the webbing goes through the loop), and that the girth hitch is positioned such that webbing going into and out of the loop are parallel, you end up with twice the tensile force being exerted on the end with the loop.

For everything to be static (no acceleration) you need all force vectors to cancel out. Also, (because we assume no friction in the loop) tension in the webbing is the same after going through the loop as it was before. So you've got the webbing coming out of each side of the loop exerting a force equal to the load you put on it, and since they are parallel this is all active force. This would put 2X the force on the end with the loop tied into it.

Of course, in reality there is friction between the loop and the strand of webbing you feed through it, so the tensile force in the webbing is reduced after it is fed through the loop, which reduces the force on the end with the loop tied in it. The strands going through the loop aren't perfectly parallel either, so the forces don't add in a perfectly linear fashion (see vector addition ). If the strands are parallel, then the strand going to the load is probably also rubbing against the tree, which reduces force on the looped end. So in reality the end with the loop tied into it ends up with a tensile force somewhere between the force being exerted by the load and twice the force exerted by the load.

I don't know if that was explained well. We're doing an anchors clinic on Sunday, and I might draw up a free-body diagram to help demonstrate that concept. If I do I'll scan it and post it to give you a visual.


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By jon jugenheimer
From Madison
May 29, 2013
hi

So the girth hitch has somewhere between X and 2X then?


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By chris21
May 29, 2013

Use a basket hitch with slings or webbing on trees it increases the strength of the sling and does less damage to the trees. This may be what Jon is referring to by "non-tightening loop".


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By jon jugenheimer
From Madison
May 29, 2013
hi

picture of a "Basket Hitch"?


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By Carl Sherven
May 30, 2013

Turd Ferguson! wrote:
I once asked a guy what time it was and he spent the next ten minutes telling me how watches are made and thinking he was a really bright guy. In the end, he still couldn't answer what time it was.


Hey now. I can't climb worth a damn, but I can sorta explain some basic engineering mechanics. Don't take this from me, Turd.


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By Carl Sherven
May 30, 2013

jon jugenheimer wrote:
picture of a "Basket Hitch"?


Single basket hitch:


Double basket hitch:


The double is useful in binding together loads with several elements. It's also useful to do two of them if you need to rig a load that would wobble around, or even slide completely off, if you just rigged a single basket to one point (for example, a beam), because it will help stop rocking and sliding. Downside is it takes up extra webbing, and increases the angles, hence it also increases tensile force exerted on the webbing, It's probably preferable to use the single basket for climbing applications.

Don't take this away from me, Turd. It's all I have. :)


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By Bill McKirgan
Administrator
From Cedar Rapids, IA
May 30, 2013
Iko

Would a wrap 3 pull 2 webbing configuration be kinder to the trees?



^^^ image from: China Lake Mountain Rescue Group
kandicemurray.com/clmrg/stretcher.html


In the past I brought lots of webbing for this: a couple of 30 foot loops.

Any more, I bring smaller chunks of webbing and connect with static line which makes it easy for me to set the power point exactly where I want it. I will use w3p2 whenever possible; otherwise, I go with basket as described above.

Another kind-tree option is to be like the Arthur Dent character in The Hitchhiker's Guide to the Galaxy and bring a towel (to pad the tree).

For pro on a TR anchor it might be best to use passive stuff (stoppers and hexes and tricams (OH MY)). I'm paranoid about someone substituting passive gear for my cams if I use them for TR.

Sorry to drift from the OP's question, but has this ever happened? Or worse, has anyone had their TR pro or part of the anchor stolen while they were at the base of the climb and out of site of the anchor?

--Bill


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By BigMoveMike
From prescott
May 30, 2013
Pente 5.11 Onsight

Things you need to lead at the lake-
1. An acceptance of getting sandbagged
2. The abilety to climbing above spaced out pro
3. the desire to run it out close enough to the ground to possible hit it(the ground that is)
4. a big set of nuts... and hexes

The rock is slick, passive pro works more reliable then cams and the routes are mostly short so you can usually get by with a single set.

Devil's lake motto- Have fun or get hurt bad!

Top roping is very convenient, top access is never an issue and there are tones of trees at the top of just about every route(95%). If your top roping leave your rack in the car and bring 60-70 feet of static line(or webbing if your cheep)and 2 locking carabiners, learn to tie a speed bowline and a BHK and you will be building anchors in two min. or less.


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By Gokul
May 30, 2013
At the "summit"

Mike J. wrote:
Top roping is very convenient, top access is never an issue and there are tones of trees at the top of just about every route(95%).


Very often, these trees are on the other side of a heavily traveled trail. Please do not use tree anchors if it means running webbing or static line across a trail. You will find gear closer to the lip, and maybe even boulders or pinches you can sling if you don't have gear.


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By chris21
May 30, 2013

This is a basket hitch as it would be rigged for a toprope anchor with a 4x4 deck post in place of a tree for this example. The webbing is tied into a loop with a re-traced figure 8.

basket hitch
basket hitch


basket hitch
basket hitch


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By Jeff Howard
From Hales Corners WI
May 31, 2013

I guess I should have been more precise. I have used both to tie off trees.

While for me a tree is always a last resort preferring hexes, nuts, etc the idea that one form of tie off is the culprit remains unproven. Both stress trees and both can cause damage if used improperly. Hopefully no single tree is used in isolation and as a part of a larger system the affects of either tie off will be muted. SInce both exert the same total amount of force on a given tree under the same conditions I should have said that a girth hitch will spread the load around the entire circumference while a basket hitch concentrates the load on roughly half. Compression of tissues occurs frequently in conditions such as the leeward side of a trunk flexed in high winds so I urge all climbers to use passive pro in the rock whenever possible.

The question of why a particular tree on the edge of a crag dies is far more complex than basket vs girth hitch. Erosion from traffic must be considered as well as necrosis from root tissues being exposed to air. Weakened roots due to roughly half of the trees structure not being well rooted is also an issue. I think of the two trees at the top of Sunken Pillar that surely have been girth and basket hitched for decades. SItting at the top of the crag the pine on the right has severe necrosis on the cliffside. Is this due to slinging or the fact that the roots on that side are exposed to the air?

So sling a tree if you have to but always strive for the lowest possible impact.


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By Ben Brotelho
From Albany, NY
May 31, 2013
Epic free solo with a pack on

chris21 wrote:
This is a basket hitch as it would be rigged for a toprope anchor with a 4x4 deck post in place of a tree for this example. The webbing is tied into a loop with a re-traced figure 8.


This anchor setup eliminates the redundancy of two biners...if one fails the whole shebang does.


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By chris21
May 31, 2013

"This anchor setup eliminates the redundancy of two biners...if one fails the whole shebang does."


don't use it as the sole anchor point (last time I checked one tree and one rope weren't redundant either) ... the two biners are so it would be clearly visible what the sling is doing for the illustration and so that one biner doesn't get cross loaded.

"Another kind-tree option is to be like the Arthur Dent character in The Hitchhiker's Guide to the Galaxy and bring a towel (to pad the tree)."

Padding the tree is a good idea.


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By Tito Krull
Jun 6, 2013

when i went to the lake with an experienced friend she taught me to do three solid placements, one anchor in direct line with rope, and 2 at 30 degrees on each side of the primary. then equalize the load force between them. these can be build from crack placements, slinging around fixed rock, or a tree, etc. is that a pretty typical TR anchor at the lake?


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By Gokul
Jun 6, 2013
At the "summit"

Tito Krull wrote:
when i went to the lake with an experienced friend she taught me to do three solid placements, one anchor in direct line with rope, and 2 at 30 degrees on each side of the primary. then equalize the load force between them. these can be build from crack placements, slinging around fixed rock, or a tree, etc. is that a pretty typical TR anchor at the lake?


That's a pretty ideal TR anchor for most any location. Of course, you're not always going to find 3 perfect spots at 30 degree intervals, so you use what you have.


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By EB
From Winona
Jun 6, 2013

"The webbing is tied into a loop with a re-traced figure 8"

No. The appropriate joining knot for webbing is the water knot.

Place as many pieces as needed to build strength not redundancy for the sake of redundancy.

The use of basket hitches is good, but one carabiner is preferred. The "N" anchor is the best quickest system for pre equalized anchors I have seen.

Sling a tree/ two bomber pieces with a sliding x, fig. 8 on a bight to the master point, back to a clove hitch to the second anchor point.

Wrap 3 pull two is slow and isn't needed.

Any TR anchor should be build for strength with redundancy at the edge and master point. Our standard is 5000lbs

think about it.. what is the KN of a #10 stopper? 2 doesn't make it to 5000lbs, therefore 3 is ideal, however 2 trees which are 20 inches in diameter, could meet the 5000lbs, therefore two points would be acceptable...


Please if these concepts are new, take a anchor class and get dialed...why not.

I have offered last year free anchor clinics at DLSp and would be happy to do so again....
Anyone interested?


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By Nick Wilkes
From Madison, WI
Jun 14, 2013
Nick Wilkes

If using static line, the tensionless rig is a nice, tree-friendly way to connect to trees.



It takes a minute to work the line around the tree 3-4 times, but the concept is beautifully simple and keeps the force from concentrating on the back of the tree trunk.


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By Skyler F.
From La Crosse, WI
Jun 15, 2013
Beautiful line at Devil's Lake

Eric,
I wouldn't mind another evaluation of my anchors as I've been practicing throughout the year since taking your course. I wish I could have been free to tag along with you guys a few weeks back. I'm interested in getting some feedback on my anchors built from gear as well as placement quality. So if you're free and looking for someone willing to follow you up any lead climbs, just let me know! I'll be around the LAX or Madison area all summer. Cheers.


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