ART Cocoon Pulley

Ekka · 11th December 2007, 04:00 AM

Hey, I've been looking at this "redirect pulley".

Like WTF?

What sort of redirect pulley only allows one leg of rope? And then it has to be threaded through not just open the cheeks, slot it in and hey presto!

This is the con of the century, redirect my ass!

There's a 3mb PDF for it here and page 14 starts the English talk.

http://www.climb-art.com/download/co...CO1_A5_web.pdf

Imagine you have an anchor point and you want to redirect to drop down on a limb. You have 2 lengths of rope that have to be captured in a redirect, old school method is 2 biners opposing gates perhaps suspended by some tape loop. But you have two legs of rope.

So, how are you going to get your lifeline (both legs) running through 2 of these if ya that rich and can afford to but two? Sure you get to feed one end through easily, that's the terminating in ya biner end (still means you have to untie etc), what about the other end, ya gonna pull the whole tail of ya lifeline up and shove it through?

Load of BS!

What ya reckon? Straighten me out if I'm wrong. They market it as a redirect pulley.

From:Doublesnapper - Advanced Ropeclimbing Technology

Quote:

The Cocoon is an innovative redirection pulley designed for the special requirements of rope climbing techniques in tree care. Owing to its versatility, however, it can also be used in a number of other applications.
The Cocoon is tested and certified for personal protection equipment (PPE) in accordance with the European standard EN 12278.
For taking up load it can either be equipped with a certified loop runner or a certified rope sling. As to which types have been approved by the manufacturer, please see the operating manual.
Owing to the completely new design of the locking mechanism, no carabiners are needed. Loop runner or rope sling are clamped directly into the Cocoon body, and protected and secured by a round nut which may simply be tightened by hand (no tools needed!). Because the smooth surface of the sphere-like screw does not offer any contact surface, the Cocoon stays safely locked. The principle underpinning this locking mechanism has been acknowledged and protected by means of an independent patent, including additional priority claims.
The Cocoon is equipped with a friction ring and a safety ring. The former increases friction on the last turns of the thread to ensure that the nut sits absolutely tight. It also keeps dirt out. The latter stays visible as long as the nut is not screwed on tightly and acts as a warning to the user.
The Cocoon not only ?cocoons? the loop runner or rope sling but it also protects the double ball bearing of the pulley.
The body of the Cocoon is made out of a massive block of aluminium (?Konstruktal?)..

Cocoon - Item No. RE71
Sling only - Item No. RE71S
Cocoon incl. Sling - Item No. RE71C

Here's some pics

Tree Machine · 11th December 2007, 06:13 AM

It appears to be a lower friction alternative to an already low-friction friction saver. It clearly is designed to be used as part of an access line component using a traditional 2:1 ascent/descent system. Advantages? It swivels.

Revolutionary components to make an already difficult system more complicated. Anything to try to make the 2:1 system easier, but the physics of the 2:1, and gravity, trump all efforts at making some part of the system easier. No matter how much gear you throw at this system, it is still just what it is.

I normally embrace new gear, but you can't use duct tape to fix the hole in the side of a ship.

D Mc · 11th December 2007, 07:49 AM

Ekka, I think you are right on the mismarketing. It seems like a decent enough pulley, certainly is streamlined, looks like it would work as either a primary tie in as an adjustable false crotch or as a tie in for a secured footlock with your climbing setup run through the pulley and attached to yourself in a normal manner. This would allow you to proceed working at any point in your footlock climb.

I disagree with Treemachine (sorry) on friction not making much difference. By far my favorite set up to date is with using the Rock Exotica swivel pulley (that does have swivel side plates for mid-line attachment and is rated for over 8000 lbs and is cheaper) as an adjustable false crotch for my primary tie in point. This, run through a Lockjack, produces virtually no friction. I can easily tell the difference between using it and using a friction saver.

Kill the friction, save the climber.

D Mc

Ekka · 11th December 2007, 11:39 AM

TM, ART also make the ART Rope Guide for your primary anchor. It's a pulley set up and depending how you install it it's retrievable.

I just dont see what the advantage of this thing is. The only thing that makes this swivel is the rope it's attached with.

Now if that rope isn't long enough and you need to fit a larger loop ... look at the little pieces you could drop out of the tree.

Sorry, this is junk IMHO.

A redirect pulley needs swivelling cheeks, or use those biners with that little roller.

D Mc · 11th December 2007, 02:59 PM

Quote:

Originally Posted by Ekka

I just dont see what the advantage of this thing is. The only thing that makes this swivel is the rope it's attached with.

Sorry, this is junk IMHO.

A redirect pulley needs swivelling cheeks.

I didn't notice that this wasn't an actual swivel the first time I looked at the catalog. Good spot!

Also it is rated for about 22kN

which is lighter than I like for a primary tie in. And absolutely, a redirect pulley does need swivelling cheeks.

But really, Ekka, you need to stop mincing your words and let us know how you really feel!

D Mc

Tree Machine · 11th December 2007, 05:45 PM

Quote:

Originally Posted by D Mc

I disagree with Treemachine (sorry) on friction not making much difference.
This, run through a Lockjack, produces virtually no friction. I can easily tell the difference between using it and using a friction saver.

Kill the friction, save the climber.

D Mc

Friction is everything, D Mc. My point was 2:1 being more motion overall, regardless of friction. 1:1, half the motions, no movement or friction of the rope at the tie-in point, at any time, just rope pressure created by your weight .

In 1:1 ascent, none of this advanced climbing gear is needed for advantage over friction. Friction is not an issue, at the crotch anyway. 1:1 friction comes at the dual ascender, and it is minimal, almost negligible friction going up.

On descent, friction is your friend, and how it is managed, (2:1 or 1:1) is your force against gravity.

I only mention this because the advantage to using ANY friction saving device is for 2:1 systems alone, not 1:1. I'll shut up now.

George Hayduke · 14th December 2007, 02:33 PM

DMC,

22kN is only about 50# shy of the ansi required 5k#. What do you expect for a primary tie inpoint? Ever tested the tree for strength?

D Mc · 14th December 2007, 03:27 PM

George, The tensile strength appears to be stronger than I thought (around 23 kN) which is fine. But still, all things being equal, I will choose a stronger tie in point and the Rock Exoc pulley is rated for a little over 8000#, is $40 cheaper with swiveling cheek pieces.

Tree Machine, I use the 2:1 and the 1:1 for ascents but I always use the 2:1 for working the tree. The actual ascent into the tree rarely takes more than 5 minutes but the actual doing of the job can take hours. That is where the reduction of friction of the 2:1 system will become noticeable. The friction reduction in a good quality pulley compared to the friction saver is noticeable. I'll take what I can get.

More motion in the 2:1, yes. But also mechanical advantage lifting half my body weight makes my old arms feel young again.

D Mc

quercus · 15th December 2007, 05:56 AM

Quote:

Originally Posted by Ekka

A redirect pulley needs swivelling cheeks, or use those biners with that little roller.

Wich one, Ekka? The one from DMM (revolver)? They can't be locked.
I've got the cocoon for about a week now and like you said it, it's junk.... Been testing it for a lot of purposes and can't seem to find one perfect purpose. I do use it now as a retrievable redirect but it's not working very well. I install it above my VT before I start climbing. Instead of the endless rope I installed a daisy chain webbing so that it can fit any branch or stem. The vt end has the pulley and the other end has the carabiner so it's retrievable with the cambium-saver retriever-balls. The efficiency is next to nothing so it's a total waste of money.
I've got a small double pulley with swivel cheeks for a 11 mm rope, but I can't seem to find a good one for a 13 mm.

There's actually one good purpose for the cocoon. Use the endless rope as prussik for the footlock rope and the climbing line with the friction hitch trough the pulley. When you arrive in the canopy you can start working immediately because the footlock line has now become your anchor point for the 2:1 system. Just make sure you install a knot under the prussik so it can't slide down as you are working. For retrieval,you can pull the double footlock rope on the ground and the knot unties. Then milk the rope (pull one end and then the other, continuously)untill the prussik gets loose. When the prussik is loose, pull one end through and the pulley comes down.

quercus · 15th December 2007, 09:14 AM

a picture of the set-up...

Ekka · 15th December 2007, 11:58 AM

Thanks, I just cant see why they went to all the trouble of making that thing?

jim1nz · 16th December 2007, 03:30 AM

Haha what ever happened to positive and constructive critisism! That pulley is one of the best enginered and well thought out design out of any piece of arb climbing equipment i have seen in a while. Just because some bloke wrote up an article saying its a redirect pulley dont mean it is. Its up to you to come up with creative ways of using such a tool. Its so easy to buy it, follow the croud and try it once only to come to a conclusion of it being shit. I have one and am using it on a rope guide with a open spliced eye insteed of the ring, you will find the pulleys dont fit well into the ring. I use it as a midline anchor pulley as it comes out of rope with no dramas at all.

Positives -

Smooth ergonomic shape stops it getting stuck!!!
Easily attached and swaped with other hardware and ropes/slings
Very light
Can take a knock, has bushings as opposed to a bearings

It does not swivel what so ever. Swivel pulleys dont work in a double rope system with a VT or similar self tailing prussic anyway, the rope twists just the same.

Ha i have to laugh at everyone worrying about the system ratings, i mean for sure 22kn is an excellent safe standard but whats the point in higher breaking strengths? Seriously the chance of your tie in point exceeding 2.2 ton breaking strength is bugger all, if so prove it...

D Mc · 16th December 2007, 07:53 AM

Jim, Glad you were able to find a good use for the cocoon pulley. It certainly is streamlined.

The point of having an excessive strength rating on equipment such as this is to compensate for wear and field abuse. You tie into a tree at your tie in point once every 3 to 5 years using that as a high lead. But you will be using the same hardware hour after hour, day after day, so when you go back to the tree in 5 years, chances are you will still be using some of that same equipment and yet your tie in point has grown reaction wood to compensate for that terrible loading you gave it last time, so is in fact stronger; whereas your equipment has suffered use and is, therefore, continually degrading.

I try to use my own judgment when picking hardware. As a for instance, for snaps on my flip line I will use aluminum. They are softer and will wear faster than the steel D rings that they are snapped into. I replace my flip lines and snaps more frequently than I replace my saddle, so want the rings on my saddle to wear the least. Anything with moving parts, such as a pulley, I want way stronger simply because those moving parts start wearing as dirt and debris start penetrating and I also, because of their price, tend to want to use them longer than other pieces of equipment.

I have no problem replacing a dinged up carabiner but am much more reticent to can a hundred dollar pulley.

I just read an article, unfortunately I can't bring up the title, on the breaking strength of crotches and was surprised at how strong they can be, even with included bark. I trust my trees because experience has given me the ability to appraise and chose appropriate tie in points. My gear I am relying on someone else to determine its strength and I do have trust issues.

D Mc

quercus · 16th December 2007, 08:39 PM

We've tried it yesterday in the set-up like my pictures showed earlier. It works very good that way, also retrieval from the ground is not a problem. seems to retrieve better with a four coil prussik than six coils. The bee-line does not slip at all with four coils but I feel better with the security knot in place though. We've been drop-loading it and the knot does not slip at all.

Ekka · 16th December 2007, 08:42 PM

Jim. I dont get it how you are using that, pics please.

Oh, that wording is off their own site!

jim1nz · 20th December 2007, 07:04 PM

Quote:

Originally Posted by D Mc

The point of having an excessive strength rating on equipment such as this is to compensate for wear and field abuse.D Mc

Hey mate,

Is that right, so if you had a climbing pulley that was rated to 35kn as opposed to 22kn does that mean it lasts longer given the same use?? I dont believe so. Thats all i ment in regard to excessive equipment ratings.

With tie in points, all i can say is there is no rating on branches so it is certainly something to think about and for sure it is a experience thing. Its ironic though, experienced guys will undoubtedly push their roping points higher that a newbie to get easy access throughout the tree. D mc your right, you yourself and every climber is responsible for their OWN life and must judge that final roping point for themselves.

Its just something to be aware of thats all.

11th December 2007, 06:13 AM	#2 (permalink)
Tree Machine Astronaut Join Date: Mar 2007 Location: Indianapolis Posts: 567	Swivel Pulley It appears to be a lower friction alternative to an already low-friction friction saver. It clearly is designed to be used as part of an access line component using a traditional 2:1 ascent/descent system. Advantages? It swivels. Revolutionary components to make an already difficult system more complicated. Anything to try to make the 2:1 system easier, but the physics of the 2:1, and gravity, trump all efforts at making some part of the system easier. No matter how much gear you throw at this system, it is still just what it is. I normally embrace new gear, but you can't use duct tape to fix the hole in the side of a ship.

11th December 2007, 07:49 AM	#3 (permalink)
D Mc Cruisin' Join Date: Nov 2007 Location: Montana Posts: 72	Re: ART Cocoon Pulley Ekka, I think you are right on the mismarketing. It seems like a decent enough pulley, certainly is streamlined, looks like it would work as either a primary tie in as an adjustable false crotch or as a tie in for a secured footlock with your climbing setup run through the pulley and attached to yourself in a normal manner. This would allow you to proceed working at any point in your footlock climb. I disagree with Treemachine (sorry) on friction not making much difference. By far my favorite set up to date is with using the Rock Exotica swivel pulley (that does have swivel side plates for mid-line attachment and is rated for over 8000 lbs and is cheaper) as an adjustable false crotch for my primary tie in point. This, run through a Lockjack, produces virtually no friction. I can easily tell the difference between using it and using a friction saver. Kill the friction, save the climber. D Mc

11th December 2007, 11:39 AM	#4 (permalink)
Ekka Eric Frei Administrator - Brisbane L5 (Dip) Hort Cert III Arb + some Join Date: Jan 2007 Location: Brisbane Posts: 5,673	Re: ART Cocoon Pulley TM, ART also make the ART Rope Guide for your primary anchor. It's a pulley set up and depending how you install it it's retrievable. I just dont see what the advantage of this thing is. The only thing that makes this swivel is the rope it's attached with. Now if that rope isn't long enough and you need to fit a larger loop ... look at the little pieces you could drop out of the tree. Sorry, this is junk IMHO. A redirect pulley needs swivelling cheeks, or use those biners with that little roller. __________________ Remember to use the "search" function, if you have answers/questions post them so everyone can benefit. Free Tree and Green Industry Link Directory Qualified Brisbane Tree Lopping Brisbane Tree Care, Consultations and Arborist Reports Forum Sponsors

14th December 2007, 02:33 PM	#7 (permalink)
George Hayduke Banned Join Date: May 2007 Location: Slickrock, USA Posts: 93	Re: ART Cocoon Pulley DMC, 22kN is only about 50# shy of the ansi required 5k#. What do you expect for a primary tie inpoint? Ever tested the tree for strength?

14th December 2007, 03:27 PM	#8 (permalink)
D Mc Cruisin' Join Date: Nov 2007 Location: Montana Posts: 72	Re: ART Cocoon Pulley George, The tensile strength appears to be stronger than I thought (around 23 kN) which is fine. But still, all things being equal, I will choose a stronger tie in point and the Rock Exoc pulley is rated for a little over 8000#, is $40 cheaper with swiveling cheek pieces. Tree Machine, I use the 2:1 and the 1:1 for ascents but I always use the 2:1 for working the tree. The actual ascent into the tree rarely takes more than 5 minutes but the actual doing of the job can take hours. That is where the reduction of friction of the 2:1 system will become noticeable. The friction reduction in a good quality pulley compared to the friction saver is noticeable. I'll take what I can get. More motion in the 2:1, yes. But also mechanical advantage lifting half my body weight makes my old arms feel young again. D Mc

15th December 2007, 11:58 AM	#11 (permalink)
Ekka Eric Frei Administrator - Brisbane L5 (Dip) Hort Cert III Arb + some Join Date: Jan 2007 Location: Brisbane Posts: 5,673	Re: ART Cocoon Pulley Thanks, I just cant see why they went to all the trouble of making that thing? __________________ Remember to use the "search" function, if you have answers/questions post them so everyone can benefit. Free Tree and Green Industry Link Directory Qualified Brisbane Tree Lopping Brisbane Tree Care, Consultations and Arborist Reports Forum Sponsors

16th December 2007, 03:30 AM	#12 (permalink)
jim1nz Afterburner is shakin' Join Date: Jan 2007 Location: Tauranga, New Zealand Posts: 296	Re: ART Cocoon Pulley Haha what ever happened to positive and constructive critisism! That pulley is one of the best enginered and well thought out design out of any piece of arb climbing equipment i have seen in a while. Just because some bloke wrote up an article saying its a redirect pulley dont mean it is. Its up to you to come up with creative ways of using such a tool. Its so easy to buy it, follow the croud and try it once only to come to a conclusion of it being shit. I have one and am using it on a rope guide with a open spliced eye insteed of the ring, you will find the pulleys dont fit well into the ring. I use it as a midline anchor pulley as it comes out of rope with no dramas at all. Positives - Smooth ergonomic shape stops it getting stuck!!! Easily attached and swaped with other hardware and ropes/slings Very light Can take a knock, has bushings as opposed to a bearings It does not swivel what so ever. Swivel pulleys dont work in a double rope system with a VT or similar self tailing prussic anyway, the rope twists just the same. Ha i have to laugh at everyone worrying about the system ratings, i mean for sure 22kn is an excellent safe standard but whats the point in higher breaking strengths? Seriously the chance of your tie in point exceeding 2.2 ton breaking strength is bugger all, if so prove it... __________________ SPEED ALWAYS FOLLOWS TECHNIQUE

16th December 2007, 07:53 AM	#13 (permalink)
D Mc Cruisin' Join Date: Nov 2007 Location: Montana Posts: 72	Re: ART Cocoon Pulley Jim, Glad you were able to find a good use for the cocoon pulley. It certainly is streamlined. The point of having an excessive strength rating on equipment such as this is to compensate for wear and field abuse. You tie into a tree at your tie in point once every 3 to 5 years using that as a high lead. But you will be using the same hardware hour after hour, day after day, so when you go back to the tree in 5 years, chances are you will still be using some of that same equipment and yet your tie in point has grown reaction wood to compensate for that terrible loading you gave it last time, so is in fact stronger; whereas your equipment has suffered use and is, therefore, continually degrading. I try to use my own judgment when picking hardware. As a for instance, for snaps on my flip line I will use aluminum. They are softer and will wear faster than the steel D rings that they are snapped into. I replace my flip lines and snaps more frequently than I replace my saddle, so want the rings on my saddle to wear the least. Anything with moving parts, such as a pulley, I want way stronger simply because those moving parts start wearing as dirt and debris start penetrating and I also, because of their price, tend to want to use them longer than other pieces of equipment. I have no problem replacing a dinged up carabiner but am much more reticent to can a hundred dollar pulley. I just read an article, unfortunately I can't bring up the title, on the breaking strength of crotches and was surprised at how strong they can be, even with included bark. I trust my trees because experience has given me the ability to appraise and chose appropriate tie in points. My gear I am relying on someone else to determine its strength and I do have trust issues. D Mc

16th December 2007, 08:39 PM	#14 (permalink)
quercus Afterburner is shakin' Join Date: Nov 2007 Location: belgium Posts: 414	Re: ART Cocoon Pulley We've tried it yesterday in the set-up like my pictures showed earlier. It works very good that way, also retrieval from the ground is not a problem. seems to retrieve better with a four coil prussik than six coils. The bee-line does not slip at all with four coils but I feel better with the security knot in place though. We've been drop-loading it and the knot does not slip at all.

16th December 2007, 08:42 PM	#15 (permalink)
Ekka Eric Frei Administrator - Brisbane L5 (Dip) Hort Cert III Arb + some Join Date: Jan 2007 Location: Brisbane Posts: 5,673	Re: ART Cocoon Pulley Jim. I dont get it how you are using that, pics please. Oh, that wording is off their own site! __________________ Remember to use the "search" function, if you have answers/questions post them so everyone can benefit. Free Tree and Green Industry Link Directory Qualified Brisbane Tree Lopping Brisbane Tree Care, Consultations and Arborist Reports Forum Sponsors