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Thin air
2006-07-11, 13:00
This is a better way to hang your hammock.
Take a length of line and make a loop. Put this line around the tree and snug it up.
You now have a lenght of free line.
Take another smaller length of line and make a COLOR=Blue]prussick[/COLOR and put it on this.
Use a caribiner or an S hook and attach it to your hammock line.
Slide the prussick to the correct length for your hammock.

There is no knot tying involved. Throw the line around the tree - clip to your hammock and slide to length.
If you have a Hennessey you can eliminate the hammock line on the hammock and reduce it to a loop to which you attach the carabiner.

I have used parachute cord as the prussick, saves weight, but needs to have the binding knot tripled in order to hold.

I had wanted to post a picture here but I do not know how to do that.

SGT Rock
2006-07-11, 14:19
Upload attachment or if it is already on the web you can post a link

blackbishop351
2006-07-11, 18:25
I'd definitely like to see the pictures. I'm not really following your procedure. I'd also thought about a Prusik, but I didn't think it would hold the weight. Pictures would help! :biggrin:

Thin air
2006-07-11, 19:36
Here goes a try at posting the pictures of this method. I managed to upload them, but am not sure if they will show on post. They came through as attachments.
We will see (or not, as the case may be).

blackbishop351
2006-07-11, 21:53
Good pix...and that WORKS?? Wow. I don't know how I'd feel about the 'tree rope' just hanging with a free end. I might want to put a stopping knot in it, or maybe several at different places. Also, is that a Prusik or a Kleimheist knot? It looks kind of like a Kleimheist, but I think it's a Prusik, just pulled to one side. The Kleimheist might work better. It's designed for directional tension. Here's a link to a decent knot page
http://www.realknots.com/knots/index.htm
for anyone interested.

If this works well, that's awesome...I didn't think a Prusik OR a Kleimheist would take the load from a hammock. I'll have to try it out.

Another thought. Use a second rope like Thin Air. Put a Figure 8 Follow-through on one end. Secure this end to treehuggers via a biner. Put a Prusik on the other end, attached to the load line on the hammock. In addition, put a Prusik on the end of the hammock line too, attached to your new rope. Both ropes could add up to the original hammock line length, conserving weight. This way, you have TWO Prusiks supporting your weight, without losing any adjustability. Just my .02 :biggrin:

Redleg
2006-07-12, 00:03
Here goes a try at posting the pictures of this method. I managed to upload them, but am not sure if they will show on post. They came through as attachments.
We will see (or not, as the case may be).
--Good pics.
I'm going to show my son (the hammock camper) this method.
This is very good(ie., COOL.)
knot work, flexability, skull sweat.
jaf

Take-a-knee
2006-07-12, 10:53
I don't think a Kleimheist would work, a Kleimheist is best used on a rope that has a weight suspended on it. I'll have to try it. The prussick will certainly work, and it is easier to tie. As long as the rope is strong enough the knot will hold. Some experimentation will be in order to find the smallest cordage that will work for the system. A prussik grips best on a rope that is about half-again larger than the prussik cord itself. IE 5mm prussik sling on an 8 or 9mm rope. Therefore, we need to figure out the smallest, lightest prussik sling that will support our weight and the smallest tree rope. Olive-drab parachute cord tests out at 375#, that is probably a good start. Here in the south I really don't think a small rope in place overnight will hurt a tree. Kern type ropes vary in the degree of "roughness" of the sheath. The rougher the rope sheath the better the prussik will grip on it.

Just Jeff
2006-07-12, 11:14
I've broken 550 cord (olive drap parachute cord) when using it for hammocks. Even when it was doubled up it broke at the knot.

blackbishop351
2006-07-12, 18:52
I had another idea just after I posted last, then kind of tried it out with my body weight.

I always hike with biners, so I plan around using a biner to attach the hammock load to the tree huggers. With this in mind, why not use a short Prusik leader with an 8 in the end? Tie the Prusik to the stock hammock load line, then just clip the 8 on the other end into the biner during setup. Quick and easy, and it doesn't require modification of the hammock lines in case it doesn't work.

I had some small climbing cord laying around. I'd been using it for clothesline, etc. I think. I don't know the exact size or load rating, however. It's just a bit smaller than the HH cord, maybe the same size. Anyway. I took the hammock line, tied an 8 follow-through around the bottom of my porch rail, then ran the end of the line up through a swing hook in the ceiling of my porch. I used my small cord to tie the Prusik leader onto the hammock line, with an 8 in the other end. I clipped a biner into the 8, ran the Prusik up the hammock line as far as I could reach, then lifted my feet off the ground while hanging onto the biner. I stayed like that for several minutes, even bounced around a fair bit. Nothing stretched, nothing gave, and the Prusik didn't budge. While this isn't an ideal test, it's fairly convincing. I'll try hanging my hammock this way this weekend. FYI, I'm between 180 and 200 lbs.

The thing I DID notice, though, was that the Prusik was damn near impossible to move after this. If you look at climbing pages, this is one of the problems with the knot; it locks TOO tight. That's why I thought maybe a Klemheist might work better. It's supposed to be easier to move after it's been loaded. I'll try that out next.

blackbishop351
2006-07-12, 20:52
Getting tired of friction knots yet? :rolleyes:

Ok so I kinda stepped up the knot test. To make sure I had ALL my weight on the line, I hung the hammock rope directly from the ceiling, and used my tree huggers as a foot rest. That way I was STANDING, with all my weight on the line and the knot. See "harness" pic.

First I tried the single-cord Prusik again. I looped the Prusik 3 times before tying off. I used the same cord as before, but with the foot loop. Held great, even after 10 mins or so, and with some bouncing up and down. See "prusik1" pic. The only problem I noticed was some stretch in the cord I used. This happens fairly often with climbing rope, but it kinda scared me. For comparison between the cord I used and HH load line, see "cordsize" pic.

Now I got a new length of the same kind of cord, doubled it over (made a permanent loop), and retied the Prusik, this time looping twice (four turns of cord). I didn't notice any difference from the first trial, except there was no noticeable stretching in the cord. Still worked great after holding my weight for several minutes. See "double8" and "prusik2" pix.

I also noticed that the Prusiks, in both cases, were a lot easier to move than when I tried this the first time. I don't know if it's because I tied them differently or because I just got better at loosening them, but they were a lot easier to work with.

Now I tested both single- and double-cord Klemhiest knots, with a couple different loop numbers each. None of them held.

So. This was probably overkill, but I'm convinced the Prusik idea works. Also, doing it this way leaves the hammock line intact, in case you decide you don't like this setup.

TeeDee
2006-08-11, 19:01
Ordered my Hennesy Ultralight A-sym, got an email its on the way.

Have been thinking about setup and want setup in the field as simple as possible.

Along those lines I read this thread, but it still requires a knot.

Will try the following as soon as the Hennesy arrives.

material:
1. 2 carabineers,
2. 2 locking cam action load straps. Usually available in tool stores, and most hardware stores. Usually located in the towing straps section. Water should have no effect on the strap material and it will not stretch under the hammock load, mine is rated at 2,000 lbs and is 20 ft by 1 inch. The length is probably excessive. I will cut and heat seal the end when I have a proper length for 2 trees separated by 25 ft.

Home prep:

Use the Hennesy recommended lashing or something else to attach hammock ropes to a carabineer. I prefer 2 loops around the carabineer and end with a half-hitch. That's what I usually use for tying a rope that will be under tension. The loop takes the load, no load on the half-hitch, which makes undoing the knot easy under all conditions. The half-hitch never binds.

Field setup:

1. Use Hennesy tree hugger around tree.
2. Use locking cam action load strapping between carabineer and tree hugger. No knots, just thread strap through tree hugger and carabineer and through locking cam and pull tight. Careful on tightening. With a cam action load strap you could probably pull the hammock apart.

Downside: strap is bright yellow. Have seen black and camo on the web. Bright yellow may be a good in some situations - keep people from running into the strap.

The tree huggers are probably still necessary, since wrapping the load strap around the tree will not allow you to properly pull the strap tight.

Weight of the load strap with locking cam action. About 3 or 4 ounces (subjective by hefting in my hand - could get a better weight by taking to post office and using their scale :biggrin:

Take down:

1. release locking cam, just like releasing the old style seat belts, lift top lever to release,
2. pull strap free of cam, carabineer and tree hugger.

Any suggestions for improving??

Take-a-knee
2006-08-11, 21:10
TeeDee, you need to get a scale and weigh all that hardware, it'll weigh half of what the hammock weighs. I'd be willing to bet a large Heineken that those friction buckles won't hold either. And Jeff said in an earlier post that he'd had parachute (550) cord break at the knot. The green paracord tests 375#, it you just tie an overhand knot to make the sling it will break at about 40% of 375, you do the math. If you use a double fishermans' knot to make the sling it will hold well over 300#. I think the prussik sling is the way to go, we'll see.

TeeDee
2006-08-11, 21:17
Thought I'd add a little more on the load strap.

I usually carry two with me in or on my backpack anyway. I have to carry 2 sleeping bags (mine and my wife's, she can't and it's well worth the weight to have her along :love:) and the load strap makes it easy to make the two bags (in their stuff sacks) into a single bundle. Plus with 20' of strap the extra 15' or more of strap makes it easy to strap the bags to my pack. The second strap comes in really handy for the same purpose on other items and the strapping comes in handy while away from home in various ways when something needs moving or hauling.

Thus, the load strap isn't something extra anyway. Just need two more for my better half's hammock.

TeeDee
2006-08-11, 21:51
Take-a-knee:

"TeeDee, you need to get a scale and weigh all that hardware"

Don't know what you mean by "all that hardware". The strapping plus locking cam weighs just over 4 oz (less than 4 1/4 oz). My balance beam postal scale is only good in 1/4 oz increments. The locking cam itself is between 3 and 3 1/4 oz. Since the strapping then weighs only about 1 oz, cutting it to save length or weight is probably not worth the effort.

Since the hammock weighs 31 oz plus 13 oz for the undercover, 44 oz total, and maybe the overcover (yes I will probably be using as 4 season shelter) that raises the total to 47 oz. That makes the strapping about 1/10 the weight of the hammock. Granted that is more than your para cord, but I'll have a pulling contest between the strapping and the paracord any day - the paracord will break long before the strapping.

The strap and locking cam are warranted by the manfacturer to 1,000 lbs (I think I wrote 2,000 lbs above - correct that to 1,000 lbs). I have used it for
about 500 lbs myself. The locking cam uses a cross hatch checked pattern to hold the strapping without slipping or cutting the strapping. The locking cam is designed such that the harder the pull the tigher the cam holds. It is not exactly the same design that those old seat belts in cars and airlines used. They used a checkered bar to hold the strap, this uses a cam action. Simpler and holds tighter the more the load. At a 500 lb load, the cam held with no visible sign of slipping and no visible sign of wear on the strap material. I see the truckers using the strapping cord to tie down loads every day. If slippage of the locking cams were prevalent, I don't think the trucking industry would be using them. If you really think that slippage could be a problem (and if I find it to be), a simple switch to a positive latching buckle with a simple locking mechism would be easy and with no weight gain.

"And Jeff said in an earlier post that he'd had parachute (550) cord break at the knot. The green paracord tests 375#, it you just tie an overhand knot to make the sling it will break at about 40% of 375, you do the math. If you use a double fishermans' knot to make the sling it will hold well over 300#."

As I wrote, the only knot I would use would be the half-hitch to end the Hennesy suggested lashing or the loop around the carabineer. In either case there is no load on the half-hitch. Thus, the knot cannot cause breakage.

I am mystified by your reference to the "sling". I am not suggesting that a sling be used. Where do you think a sling would be used in my suggestion?? No sling - no overhand knot, no breakage.

Please clarify where you think I am suggesting to use sling.

Just Jeff
2006-08-12, 00:22
TD, maybe I'm missing something. Where are you using parachute cord in this setup?

TeeDee
2006-08-12, 15:15
Just Jeff - I'm not.

Somehow, I think I confused everybody. I'm not using para cord at all.

The setup would be:

Hennesy rope to carabeineer to load strap to Hennesy Tree hugger.

The only knot would be the one attaching the Hennesy rope to the carabineer and if you use the Hennesy recommended lashing, the only knot would be the half-hitch. If you use the doube loop around the carabineer, again the only knot would be a half-hitch. The Hennesy rope to carabineer attachment could be considered permenent.

Use the locking cam action load strap to tension hanging the Hennesy.

No knots to tie or untie.

The locking cam action would replace the knots.

Simple.

Follows the "KISS" principle: Keep It Simple Stupid

Knots are complicated. The load strap is simple and quick.

TeeDee
2006-08-12, 16:29
I dug out my book on knots and scanned the hitch I plan on using to attach the Hennesy rope to the carabineer - It's called

"Round Turn and 2 Half Hitchs"

Which is exactly what it is.

I have attached an image of the scanned page:

Be careful on tying the half-hitch. If you go the wrong way, funny things happen.

TeeDee
2006-08-12, 16:55
I scanned the table of contents of my knot book and found the Prusik and Klemheist knots.

Are these the knots you were using?

Just Jeff
2006-08-12, 19:44
When I hung at home in SC, I'd put a carabiner on the huggers, then just tie the HH Spectra to the biner with a double slipknot. Not even a real knot - just a slipknot, then another one through. Didn't have it bind or slip, and who can't tie a slipknot in 5 seconds? Just pull the free end to undo it.

If I were worried about tying knots, I'd probably do it this way. There's a pic of it at the bottom of this page if you're interested:
http://www.tothewoods.net/HomemadeGearHammockSupports.html

JAK
2006-08-12, 20:55
Is there a need to fine tune the ammount of hammock sag once you are in it?Has anyone used a light block and tackle on one end that they can reach up and adjust? I don't know, but you might want to check out a trapeze cleat at a good marine supply store like West Marine. Very nice ropes also if you need something stiff rather than stretchy, and easy to tie and untie. Kevlar, Dyneema, Spectra, Prestretch Dacron.

http://shop.ldcracingsailboats.co.uk/index.asp?selection=detailed&uid=5262&itemtitle=New%20Trapeze%20Cleat

Check out the bridle rope on this page. It is what is used with the trapeze cleat. The crew hangs from the mast on a steel rope, but there is a short adjustable bridle.
http://www.jimyoungsailing.com/g_rnl.htm

TeeDee
2006-08-18, 22:22
Received the HH Ultralight the other day.

Immediately went to the basement and set up the hammock with fly and undercover. Setup as per Hennesy instructions.

Installed the snake skins and then took the hammock down.

With the snake skins I re-installed the hammock, again as per Hennesy instructions. Repeated 2 or 3 times.

Observations:
1. I had trouble getting the slack out of the hanging ropes. Install, then tighten. I have always had trouble when tying up a rope that has a load and I am attempting to tighten - The rope always seems to slip back a fraction of an inch when tightening the knot which of course leads to some slack that I don't want. If I compensate when pulling the rope tight, I run the risk of pulling to much and doing damage.

2. A multi-step process. Tighten, sit to pull slack and retighten. Repeat if necessary.

After setting up and taking down a few times as per Hennesy instructions, I took 2 Black Diamond neutron carabineers, fastened the hanging ropes to the carabineers (one per rope) about 4 inches past where the fly tensioners pulled the fly tight. I used the round turn and half-hitches, but any knot that will hold the load would be appropriate.

Then I used a load strap to attach one carabineer to a tree hugger. Pulled the strap tight. The cam lock locks the strap in place, no slippage. Repeated on other end.

Sat on hammock and then checked for slack.

None.

Took hammock down and setup again using the load straps with the locking cams. Repeat.

Observations:

1. setup is faster - no knots to struggle with (enjoy tying, untying :) ).

2. no slack after sitting on hammock (conjecture - the slack may develop because sitting/lying on the hammock simply pulls the knots/lashing tight - pulling all slack out the knots/lashing - with the load strap and locking cam there is no slack to pull)

3. I was wrong about still needing the tree huggers. Done properly the load strap acts as it's own tree hugger. The load strap and the Hennesy tree huggers are both 1 inch wide. With the load strap, I now have 20 feet of tree hugger, well probably closer to 15 feet. Won't handle a grown redwood, but will handle a heck of a lot more than the tree huggers will. My first choice, and only choice, for setup in the backyard was too big for the tree hugger by about 12 inches. So forced to use the load strap without tree hugger anyway.

4. Setup and takedown much, much faster. No knots/lashing to struggle with (enjoy?). Instead of breaking fingernails on loosening knots, I simply lift the cam locking lever and the strap slips loose. The knots on the carabineers are permanent. Tye once and forget. Using the straps has its own challenges, but compared to knots they are trivial. The only challenge I found is during setup - after afixing one end to a tree, getting the other end hung while holding the hammock with one hand and using the other two hands to encircle the tree with the load strap or tree hugger is challenging. But I have found that with one or 2 practice runs and a little thought before hand, getting the knack of doing it is really quite easy. It just omes down to devising a strategy that works for you.

5. I can center the hammock between the trees very easily. Just setup and ignore end distances.Then when both ends have been pulled tight, compare distance on both ends, loosen shorter end by lifting cam lock lever(keeping hammock off the ground) and tighten longer end. Repeat loosening and tightening as necessary. Since loosening and tightening is now as simple as releasing the cam lock and pulling the opposite free end to take up slack, getting the hammock centered is trivial and done in less than a minute.

6. The load strap with cam lock is heavier than cord, probably about 4 to 8 times the weight. But we are still in the range far less than 1 lb. I'll take the weight for the convenience. Of course, others will disagree and would rather forgo the weight and stick with their knots/lashing. Their choice.

In the future I am going to be watching to see if using the load strap and cam lock eliminates the need to retighten after sitting on the hammock after initial setup. If so, then the straps have also eliminated one further step in setup which makes setup that much quicker.

Also, I will be watching to see if the cam locks slip as somebody here was concerned about. I personally doubt that is a problem. After using the straps to lift in excess of 500 lbs with no slippage whatsoever, I doubt that my weight is a problem for the locking mechanism. Also, while driving around today, I noticed a bike rack on the back of an SUV. The straps weren't as long and they were black instead of yellow, but the locking cams were identical. From appearances, the bike rack had been strapped on the back of the vehicle for many, many months if not years. From the appearance of the half-hitches used to keep the loose ends from flapping, the hitches hadn't been touched since the rack was installed. All of the jostling and bumps taken driving around (also the rack was installed on the full sized tail gate of the SUV and had been subjected to many openings and closings of that) would suggest that slippage was not a problem.

To Do: I want to replace the fly tie-downs installed by Hennesy with Dyneema cord and micro tensioners from backpackinglight.com (much stronger - the Hennesy tie downs seem rather flimsy to me). The cordage and tensioners arrived in the mail today, so will be doing that soon. May install the Tarp tensioner as described on Just Jeff's web site also (Thanks Jeff for that idea.).

Looking forward to many comfortable nights off the ground.

TeeDee

Just Jeff
2006-08-18, 23:22
May install the Tarp tensioner as described on Just Jeff's web site also (Thanks Jeff for that idea.).

NP - but it was donredondo's idea posted right here on hikinghq.
http://hikinghq.net/forum/showthread.php?t=1343

Enjoy your new toy...you addicted yet?

peter_pan
2006-08-19, 10:46
TeeDee,

you might wnt to rethink your fly/tarp ties plans....most folks want the cords to fail before the tarp or tarp tie out fails....just a thought.

pan

TeeDee
2006-08-19, 16:38
peter_pan

Thanks. On reflection, I think you are probably right. Will keep current tie downs and see how things work out.

Just Jeff - "you addicted yet?" Definitely yes. The advantages far outweigh the few disadvantages I haven't found yet :elefant:

TeeDee

jazilla
2006-08-23, 12:31
I was reading this thread and its about something I have been thinking about all week. I saw in I think Quartermaster mag a cam lock for cord. What if you could run the Hennessey cord through the tree hugger then into the cam lock. No knots or lashings. The one I saw in Quartermaster said load up to 500 something. I can't find it on the website or anywhere on the web. I have found something similar but I think its for too big of a rope.

http://www.ezty.com/locks.htm

TeeDee
2006-08-23, 19:13
That would work also - no knots, just lock the rope in place. I rather doubt it would slip, if it did anybody's boat tied up with it would be floating away.

Easy setup and take-down.

What is the size of the hennesy hanging ropes?? The smallest the E-Z-Ty takes is 3/8".

I think I'll stick with the load straps and leave the tree huggers at home. Besides I already have the load straps.

TeeDee
2006-08-23, 21:32
I thinking further about the cord cam lock, I realized that you will have a problem using it with the Hennesy hanging rope.

You have no way of forming a closed loop.

To use the cord cam lock to hang the hammock, you have to have a closed loop. That you will not be able to do with the hanging rope. You would have to form a loop at the end of the Hennesy rope (or use a carabineer), then take another cord to form a loop from the Hennesy rope to the tree hugger. Thus you have replaced the load strap with a rope and you still need the tree hugger. I don't need the tree hugger with the load strap - the load strap is it's own tree hugger.

I have also realized, for those who don't hike with carabineers, you don't need the carabineer at the end of the Hennesy rope in my setup, just form a loop at the end of the Hennesy rope. I have tried that, and to be truthful, I find the use of the carabineer is easier. Just my opinion though. Your milage may vary.

TeeDee

oneshot
2006-08-24, 06:28
Has anyone thought of using a pair of ascenders?? They are light and they are strong and if the spectra is from 3/8 to 1/2 inch in diameter they will work.

Take-a-knee
2006-08-24, 08:59
The only ascender light enough to be considered is the Petzal Tibloc at 39 grams. Once it is loaded (tightened) there is no good way to release it. It might work for one end. It would require a section of rope at least 8mm in diameter for the ascender to grip, that would be a rope much heavier than needed to support the hammock and occupant. A climber friend of mine has some Tiblocs and I plan to check it out and weigh everything.

TeeDee
2006-08-24, 18:36
Just looked at a picture of the Tibloc - never used one, but from the picture it looked like it had some rather nasty spikes on the inside to grip the rope. Seems like that would do some damage to the rope. Especially if it was being applied in or near the same spot repeatedly.

TeeDee
2006-08-24, 19:00
Just checked the Harbor Freight Tools web site - that's where I got what I call a load strap. They call it a lashing strap.

I bought a package with two, each 1" by 20'. I paid approximately $10 for the pair.

Here's what they list on their web site:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=40063

That page lists a single strap and only 12' long. Seems the items in the store are packaged slightly differently.

That will give you a picture of what I am using anyway.

Take-a-knee
2006-08-24, 20:49
I've used a similar strap to lash a canoe down for several years, I don't recall ever finding a strap less than snug when I get where I'm going, usually about fifty miles from home.

TeeDee
2006-08-24, 21:07
"I don't recall ever finding a strap less than snug"

I don't seem to be reading that quite right - does that mean the strap was tight or loose??

As I get older, a state of cinfusion becomes more natural

Take-a-knee
2006-08-24, 22:25
By "Never less than snug" I meant to say always snug...never loose, not even once. I still think prussiks will work as well as these buckles if you can get everything sized right but those buckles will certainly work. I agree with Turk that some guys go overboard trying to shed weight but I do try to pare down where I can. I have a Hennesy expedition on the way and the nights are starting to get cool enough here to sleep outside and I'll start playing with the prussik, the buckle and the ascender soon. I also ordered a one ounce carabiner tonite that I plan to try to use with a trucker's hitch to support one end of the hammock. You can tighten a truckers' hitch tighter than it needs to be, and it just pops free when you need to loosen it.

jazilla
2006-08-25, 09:26
TeeDee, the one at harbor freight show max load 300 or so lbs. Are yours the same and how much are they rated? When I first got my hammock i thought about ratchet straps. Thats when I was introduced to light hiking and decided they where too heavy but I like the concept.

TeeDee
2006-08-25, 19:12
The packaging labeled the straps at 1,000 lbs. From what I have seen on various sites, I believe the cam locks are probably rated at 333 lbs, so that makes the combo 333 lbs.

Ratchet straps are nice, but the ratchets are bulky and heavy. The cam locks aren't. In stowing the straps, I wrap the strap around the cam lock and use plastic pins (like hair pins the ladies use) which I got at the fabric shop - they use the pins to keep fabic on the bolts from unraveling. Just asked if i could have a few since they just throw them away.

Also, I would be very cautious with the ratchets, you can pull a lot more tension than you realize and maybe damage the hammock.

Turk
2006-08-27, 01:12
Seen this on BPL. Thought this might fit this discussion very well.
Pretty cool system. Night Ize no-knot line tensioners. In size large you get
150lb working load, and at only 2.2oz for the pair?!? Double up and you
could probablly sling a hammock without failure. talk about quick and
easy adjustment. Worth looking into, or copying the design and fabing your
own out of heavier aluminum.
http://www.niteize.com/Images/product/hardwareaccess/figure9/figure9_large_feature.jpg


check it out.
http://www.niteize.com/category.php?category_id=29
http://www.niteize.com/productdetail.php?category_id=29&product_id=137

the video demo is good too.

TeeDee
2006-08-27, 17:36
Turk - those look to be way cool - I'm addicted to gadgets.

Have ordered 4.

If I can use those to replace the cord locks (not on bags) I use, then I could accomplish the same end with half the cord.

blackbishop351
2006-08-27, 18:19
Somebody posted about these things on the Hammockcamping group too.

There's two problems that I can see:

1 - Seems like the teeth would eat up a rope pretty quick. Plus, I use straps.

2 - The load rating isn't high enough. Hammocks exert a ~700 lb. static load on the suspension lines. You'd have to use several of these gadgets to handle the load, which would make the system more complicated than I'd want to use....not to mention heavy.

Turk
2006-08-27, 19:33
TeeDee, when you get them, let us know how they work out.
I am interested in fabing one up in the machine shop to handle 800-1000lb load.

Take-a-knee
2006-08-27, 19:59
Black Bishop is correct, I'd forgotten that the load is greatly increased when the load is placed horizontally. I had learned this was the case with climbing anchors but I was to stupid to apply it to hammocks. I'm pretty sure Petzal's website goes into this in depth if anyone cares to look at it.

Thin air
2006-08-28, 11:30
I am curious about these posts about load strengths. Some state a load of 700 # and that a horizontal load is much greater than a vertical load. There are other postings with other load factors and numbers.
Why would horizontal be any greater?
Plus why is a load (one human, more or less 200#) exerting a force of 700# on a hammock line?

I am the original poster this thread and I had mentioned using parachute cord as the prussik. Now granted that sometimes this thinner cord is a bit harder to lossen after a night in the hammock, it has held for me (185#) in a HH Exp a-sym.
I also use a non climbing carabiner in my setup stamped with "safe working load 150 lbs".
Never had a problem with failure despite moving around as one does in a hammock.

BTW - considering the recent posts about straps. I have used climbing webbing instead of rope, but used my prussik setup on this webbing. Since webbing is rather slick, you can get a slide factor with the prussik, but anyone using the "straps" mentioned recently would probably not, since those straps tend to be of a rougher surface.

Just Jeff
2006-08-28, 12:55
Because it's a calculus function. Basically, if you hang your hammock tight, like a HH with a ridgeline, the force goes way up. If you hang with a lot of sag, the weight drops to only a few hundred lbs per support.

And the force is actually on a vector parallel with the hammock support - vertical load is half the user's weight per strap, and horizontal load is determined by the angle of the strap's hang - and both come together along the direction of the hammock support. The force on the support rope is:

h = (.5 x user weight) / sin(support angle)

There's an excel spreadsheet in the files section of the Yahoo hammockcamping group that's worth looking at if you still have questions. I think it's in Youngblood's folder.

blackbishop351
2006-08-29, 03:56
Yeah Youngblood has an Excel file all nice and laid out for you if you're interested. Good thing to have around if you don't like math.


Because it's a calculus function.

Technically, it's a Trigonometry thing, not a calculus thing....but I suspect I'm the only one here who cares :biggrin:

Thin air
2006-08-29, 11:48
>>>>>>>Because it's a calculus function. Basically, if you hang your hammock tight, like a HH with a ridgeline, the force goes way up. >>>>

I believe you.
Math never was my strong point and perhaps that is the only way to explain these forces. If it is, I will have to be satisfied with pure belief.
But, is there a way to explain to a layman how this might work??
Is the ridgeline on the HH subject itself to immense forces?
Cause it seems that some of these forces, per the math, must be quite demanding on whatever you use to hang a hammock. Kind of makes me wonder about how people in unsophisticated math places, like the Yucatan where they sleep in hammocks as a lifestyle, manage to use plain old rope or whatever else may be lying around to string up their hammocks. Some of the math and the loads given (I've read) makes me wonder about the use of anything less than the best cordage.
To a simple math guy like me I am baffled as to why if I string a rope from an overhead branch, stand my 185# on it and it doesn't break, that somehow I might exert a force so much greater when I hang my hammock that the rope NOW might break, doesn't make sense.

"...if the bough breaks, the cradle will fall"

I only pursue this line because so many people have posted regarding straps and strengths. Just how relevant is it to worry about the strength of straps you buy that are already made for circumstances such as holding down boats and other loads and some that are tighted by cam leverage even.

blackbishop351
2006-08-29, 21:13
Like Jeff said, it's a vector thing. If you're really interested, join the HammockCamping Yahoo group and check out the Files section. As previously mentioned, Youngblood has an Excel file (under Youngblood, I think) that will calculate the suspension force for you, depending on the hanging angle. In my folder (Blackbishop's stuff) I posted a graphical representation of the forces involved, plus a separate file with the math.

Just Jeff
2006-08-29, 21:40
Rope can be pretty strong - but what they use in the Yucutan isn't designed to be low-volume and lightweight like we generally like our gear. You don't really need to "worry" about it....just get something with a working load over ~600lbs and you should be fine. Low stretch is good, too.

Here's a quick experiment to help you understand. Tie one end of a 15' rope to a tree and put a 20 lbs weight in the middle (or two jugs of water or whatever). Stand directly over it and pick it up off the ground. Pretty easy. Now grap the other end of the rope and pull until the rope is perfectly horizontal. You can't do it...the closer you get to horizontal, the force required to go higher increases, and increases, and increases each time.

Or you can just go on belief like you said. 550 cord is rated to 550 lbs, and I've broken it on two separate occasions in my hammock.


Technically, it's a Trigonometry thing, not a calculus thing....but I suspect I'm the only one here who cares

Hehe - I bet you're right on both counts! :)

Take-a-knee
2006-08-29, 22:23
"550' cord usually isn't...the white lines that comes off of a reserve parachute are actually 550 lb test, a reserve is smaller and has fewer lines so they are thicker. The green cord, from a main parachute, is "375" cord. For those who belong to the "I don't know no knots, I just tie-a-lot" school of knot tying, your knots will break at about %40 of 375 lb.

TeeDee
2006-09-02, 21:02
The figure 9 gizmos arrived on Friday. Had some fun experimenting with them.

They are a pretty ingenious device.

The first use I have for them is putting up my rain fly over the hammock. I could see immediately that I will be using them for that. I will definitely be using the figures 9s for this exclusively in the future. I carry the fly separate, not in the snakeskins. Keeps anything wet outside of the snakeskins and the fly is the first thing I put up and the last thing I take down. That way I have some protection from the sun and rain while putting up the hammock itself - and the hammock stays dry under the fly all the time.

With two lengths (say 12') of paracord, I will be using one figure 9 on each end of the fly - around the tree, through the loop/O ring/D ring on the fly/tarp back to the figure 9, connect one end of the cord to the figure 9 and then use the figure 9 on the other end to pull tight and secure, a quick wrap, pull and wrap again.. Quick and simple. Disconnecting from the figure 9 is just as easy - no knots to fumble with when the fingers are cold and wet and stiff. Easy to do in mittens/gloves also. Try tying a secure knot in mittens. I suppose some people could, I never could.

I couldn't give a definitive answer on the wear on the paracord after repeated use, but I doubt that it would be a serious problem from my limited experience. It could be more of a problem on dyneema or spectra which have the plastic coating. It could be possible for the teeth to wear through the coating. Again, from my limited use, I doubt that it would be a problem though. When the cord is wrapped around the figure 9, the teeth don't really put a heck of a lot of strain on the cord and the cord isn't slipping/sliding through the teeth. Most of the strain is taken by the wrapping and not the teeth. When the cord is released, again there isn't a lot of pulling to abraid the cord. Just my opinion from limited use. Ask me again after several years use with the same set of cords. My opinion may change ... or not.

One use I found that isn't mentioned by the figure 9 site or the card attached to the figure 9 - it can be used to connect/join two ropes/cords. They only depict it's use for creating loops. But then think of a loop made with the figure 9. Now cut the loop and you have two ropes/cords joined by the figure 9. Just use 2 separate cords/ropes to start. Of course you have to make sure the joined ropes/cords are under some tension at all times or the figure 9 could loosen. That could a pro or con depending on the situation.

I think that when the situations present themselves, other uses for the device will surface. It is one of those things that is really, really simple and you hit yourself saying why didn't I think of that and then you proceed to find all kinds of differing situations where it is useful.

The figure 9 has illustrations of how to use it laser engraved in the device itself. Not that using is all that hard to begin with.

oops56
2006-09-03, 01:01
Well knots or just knots i got this hammock so we went camping this week its a nylon made by amazonas its the traveller. Did not over night sleep but took a after noon nap after 3 or 4 trys got how to get in it. The first time it look good so lets try it try to get in butt hit ground. Now i made my own huggers so all had to do was slide them up higher and no special knot just regular knot i finely made it and had a nap. o the cost of hammock $20.00
click pic. for bigger
http://i33.photobucket.com/albums/d52/oops62/th_hammock.jpg (http://i33.photobucket.com/albums/d52/oops62/hammock.jpg)

TeeDee
2006-09-06, 21:37
Just to highlight another no knot hammock hang - over on the Yahoo hammock group, somebody has posted a means of hanging the hammock using webbng, a ring and a toggle.

Light, secure and easy to use.

TeeDee

mandorak
2007-06-19, 04:17
look this system , super fast installation , no knot and full respect for the trees :

http://www.ticketothemoon.com/images/faq-howToAttachTheRope.gif

Thudley
2007-06-19, 09:24
Here's a quick experiment to help you understand. Tie one end of a 15' rope to a tree and put a 20 lbs weight in the middle (or two jugs of water or whatever). Stand directly over it and pick it up off the ground. Pretty easy. Now grap the other end of the rope and pull until the rope is perfectly horizontal. You can't do it...the closer you get to horizontal, the force required to go higher increases, and increases, and increases each time.

That's the best intuitive description of this problem I've seen . I've worked out the trig, but "seeing" it in your mind's eye is 100% better than looking at the math on paper. I'm a big believer in such illustrations.

Congrats, Jeff!

Ed

Iceman
2007-06-19, 10:32
look this system , super fast installation , no knot and full respect for the trees :

http://www.ticketothemoon.com/images/faq-howToAttachTheRope.gif

Mandorak, are you associated with this company? Because when I google your name (Mandorak) and the word "Hammock", I get a hit on a page from the company that your keep referring us to in your first two posts on this site;

http://tttmshop.com/Travel-Hammocks/Friends.html

This looks a bit suspicious to me.

Are you associated with TTTM?