Knot Questions

The purpose of this entry is to present some questions on knots.

Anyone using the Machard Tresse or Valdotain Tresse knots? Did anyone evaluate and decide against using them? See "The Tree Climber's Companion" Jepson 2nd edition page 84 for a reference.

Anyone know the history on the Distel knot? It seems to be a an engineering wonder. Is it finding a lot of use?
http://www.arboristsite.com/attach/8460.jpg

Regards,
Jim

I'm fond of the distel. It is great for quick ascents.

I often climb a pair of willow oaks. I can set my line at about 50' and be just under the tie-in in about 5 min. I'm not comfortable with it yet for moving around in the tree, but I can grab way above my head and pull hand over hand and tend the knot with one hand taking in 15-20' of line at a time. When more rope is paid out under the hitch it will tend itself, NICE.

Put it this way. I set my line, my sons line, climbed up( 40' ) and set the tail of my line over another limb for my daughter to climb on in less than 15 minutes; using blakes that time doubled.

Climb Safe!
Icabod

By the way, I invented a slack tender that replaces the micropully commonly in use. Nick perfected it and makes several really nice versions of it. There is a thread about it somewhere on this board. Drop Nick a line for info.

When climbers make the move to a new climbing hitch its a good idea, like always, to start out low and slow. Set a rope in a tree and tie in while on the ground. Do some limb walks out away from the trunk. Footlock up a couple of catches and then come back down. This will break in the cord and allow for some final tweaking.

Another good idea is to tie a stopper knot in the climbing rope a few feet below the hitch. With the stopper in place the climber will only drop down a short distance in case everything goes pear shaped.

I gave the Distel a run on my SRT setup and now have moved onto the VT. I couldn't find a loop combo with the Distel that had the right slip/grab characteristics. This will be a slow process of elimination to find a oood SRT hitch.

Tom

I've been looking at switching to an advanced hitch, probably the V.T., from all the good things I've heard about it. By doing a search on the Arborsite.com website, it looks like some others have used 5/16" (8mm) cord for tying the V.T. on the Fly rope. What do people here use?

If you're making your first step from using a split tail to a closed friction hitch I would recommend a distel. The distel is much more forgiving about how long the bridge is. With th VT/MT they can be a bit touchy. If they're too long they have a reputation for not grabbing right away. Until you develop a familiarity with the cords and the differences of using a closed hitch, the distel is less complicated.

I like using New England Econobraid, either 3/8" or 5/16" It will depend on your weight and climbing style. Try them from the ground first. Then, when you start to use them in the tree, tie a tigure eight on a bight as a stopper knot below your hitch in case it does slip. You won't take a grounder then.

Tom

http://www.proclimber.co.uk/knotting-shed/proclimber-knotting-shed--arborist-treeclimbing-hitches.htm

http://www.arboriculturesolutions.com/advanced_friction_hitches.htm

These images are being found through www.google.com then select image search.

The purpose of this entry is to propose a variation to the Valdotain Tresse knot where a strand of cord following the last braid is made into a loop before attaching to the carabiner. This is like the last loop on the Distel. The mechanical advantage is that the cord will "bite" into the climbing rope upon the initial loading, setting the entire knot in place. The benefit is a reduction in the risk of slippage with a broader range of cord type.

Tom Dunlap and David Risley have shared circumstances where the Valdotain Tresse knot will slip. In a similar fashion, Jepson in "The Tree Climber's Companion" 2nd edition on page 85 cautions that the Valdotain can fail to grab.

When the cord makes a tight loop around the climbing rope on the last braid of the Valdotain, a more responsived bite into the climbing rope is gained. This proposal is untested across multiple cord types and warrants the caution of being tried "low and slow".

The best feedback would be for someone to try this added loop with a cord type known to fail with the Valdotain.

Two approaches of making the loop with a single VT strand were used. One was to create a loop around the climbing rope only. The next approach was to make a loop around the other VT strand and climbing rope. The second approach seemed better for releasing pressue.

The Valdotain Tresse knot is very symmetrical, and as such it has an artistic presentation. This variation distorts the symmetry, but it seems to function thus far.


Regards,
JimK

Originally posted by David Risley
I have used both the Distel and V.T. quite a bit, and like both. They are being widely taught to arborists as modern climbing knots, partly because they are so responsive, but also because they are closed systems with inherent safety benefits. They are, of course, used solely in split-tail type setups, are tied close to the saddle, and are invariably tended with a micropulley.

The V.T. is the most responsive of the two, but is also more sensitive to differences in cord material, so you have to be sure to get the right combination of cord and number of wraps/braids to make it work reliably. I use it with Ultratech, which works very well in the classic 4-wrap/4-braid, or even 3-braid configuration.

One important thing about the V.T. to be aware of -- and wary of -- is that, when tied using new, stiffer cord, it can fail to catch and tighten up on the climbing rope when you descend. So, it is a good idea to work any new cord until it is good and limp before using it for a V.T., and then keep an eye on it to make sure it catches before beginning the first few descents. After a few uses, that potential problem disappears. When you get it right, it is hard to beat the V.T.

I use the V.T. with a tending micropulley on my lanyard line because it works more smoothly for that application in both directions than any other knot or mechanical device I have tried.

The Distel is a little less responsive, and tends to tighten up under load a bit more than you may wish at times, but it is less sensitive than the V.T. to differences in cord material and diameter, and is completely reliable, well suited for both beginner and expert alike. I suspect it is the most likely of the modern knots to become a classic standard. I use 10 mm. Tenex for my Distel, but it will work with almost any cord material.

I prefer the Distel to its cousin, the Schwabisch, because the Schwabish puts more of a bend in the rope. But, the Schwabisch is tied and performs much the same as the Distel.

Hey David, I have been meaning to try a vt on a steel core lanyard for a while now, seems you're using one, could you recommend what combination of vt cord/lanyward please
appreciated
steve

The purpose of this entry is to share that additional testing with the Distel bottom loop placed on the Valdotain Tresse continues to show that it minimizes slippage. To test if this Distel styled bottom loop was a benefit, a Valdotain Tresse was tied with 2 top wraps and 2 braids. It wouldn't hold under any circumstances. This established a fail control. Next, the "bottom braid" was looped around the "top braid" and climbing rope just before the caribiner attachment. More friction resulted from the addition of the Distel styled bottom loop. It could establish a set-point where slippage would halt. However with just 2-wraps and 2-braids, the risk of slippage continues even with this V.T. variation. The point being established is that a loop at the end of the braids will improve friction, making the VT less sensitive to set-up conditions.

There is another way to visualize this knot variation - hopefully easier. Imagine a Distel with braids like the Valdotain Tresse between the top wraps and the last loop. In this variation, the bottom Distel loop goes around the other braid, encircling both the braid and climbing rope.

Besides adding more friction, this loop kept both braids better organized and appears to have an equal ease of movement on unloading.

In the near future a pic will be provided. However, if someone can translate this narration into a knot and take a photo, you are invited to do so.

Regards,
JimK

http://storrick.cnchost.com/VerticalDevicesPage/Ascender/SemiMechPages/CarabKnotD2.html

http://storrick.cnchost.com/VerticalDevicesPage/Ascender/SemiMechPages/CarabKnotD2.html

In the near future a pic will be provided. However, if someone can translate this narration into a knot and take a photo, you are invited to do so.


Hmm...I can't visualize it. Quite interested in seeing your photo when you put it up!

well just for the record, i see the point

I had posted two previous pics of a modified Valdotain. They didn't have the loop modification tested. This pic does. Your variations and results are welcomed.