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TeeDee
2007-01-15, 22:08
I have finally decided to ditch the cam locks I used on the polyester webbing I use to hang my hammock. Didn't have any problems with them, but I continued to have 2 doubts:

1. I couldn't find the strength of the cam locks. The manufacturer cautions about exceeding 300 lbs. That did bother me even though I experienced no signs of failure whatsoever.

2. In releasing the cam locks in the morning, they are tight and the teeth grip and bite into the webbing. I was worried that the teeth on the cam lock could eventually abrade the webbing.

So I removed the cam locks and replaced each with 2 descending rings:

http://www.summithut.com/catalog/remap/product.asp/DeptID/327/SortOrder/1/pfid/14116/

These rings are very light - 2 weigh in at 0.8 oz. The webbing with 2 rings weighs a little over 3 oz. Will have to take to the post office to get a more accurate weight. That makes the suspension, including the Black Diamond Neutrino carabiners come out at about 4.5 oz for each end or 9 oz total. Maybe I could find lighter carabiners, but the Neutrino is the lightest that Black Diamond makes. I could replace the carabiners with bowlines and bring the total weight down by 2.5 oz, but I like the convenience of the carabiners and I'm not that obsessed with weight.

By sewing 2 rings into loops at the end of each webbing, I have a double ring buckle. The double ring buckle is as easy to use as the cam lock buckle (with the webbing at 1" width and the ID of the ring at 1.5", they are very easy to release, just pull the loose end to a right angle to the force on the webbing, simple). The double ring buckle tightens in the same manner as the cam lock buckles.

I don't think I have to worry about the rings abrading the webbing with the double ring buckle and I no longer have any lingering doubts about the strength of the buckle. With 2 of the descending rings holding the weight, the buckle is good for whatever load the hammock places on them. Also, I girth hitch the webbing around the tree and so have a double length of webbing from tree to hammock. Unless that is, the span between trees is too great and I have to run a single length. Haven't run into the situation yet. The webbing is rated by the manufacturer at 1,000 lbs, so even at a single length between tree and hammock, I should be okay.

I like the webbing for suspension - it acts as the tree hugger and suspension all in one.

Turk
2007-01-16, 15:39
Nice rig!!
Going to have to try that out. I also recently found some SUL 25kn gated
biners. Think i will attempt your system in the garage.

Seeker
2007-01-16, 18:09
how superultralight, and what does "25kn" mean? (i rappelled in the army, so i probably used to know.)

someone, over on practical backpacking i think, mentioned some that have a 1500lb capacity and weigh about 1/2 to 3/4 of an ounce... i forget exactly, but i was impressed... but he didn't say what they were or where he got them. just posted a picture from his rig. would love to get a set. my wire-gate set weighs over 2oz.

TeeDee
2007-01-16, 18:09
Nice rig!!
Going to have to try that out. I also recently found some SUL 25kn gated
biners. Think i will attempt your system in the garage.

My God - 25Kn - you could hang the moon on those.

What make are they and do you know how much they weigh and where did you find them????????

Ahhh. I take that back - I just checked the specs on the neutrino - they're rated at 24 Kn on the major axis also, that comes to 5395 pounds-force for those of us that grew up on the English system.

kN - kilo-Newtons, SI Metric unit of force - Kg * m / sec * sec

1 kN == 0.22481 pounds-force

Turk
2007-01-16, 19:43
My God - 25Kn - you could hang the moon on those.
Ahhh. I take that back - I just checked the specs on the neutrino - they're rated at 24 Kn on the major axis also

ya, I was going to say, it isnt anything too special. I think its pretty standard
in the climbing industry. Something about safety factor of 10x above working
load or something of that nature.

This looks almost identical to the ones I picked up.
http://www.backcountrygear.com/catalog/climbdetail.cfm/OP110
Same style, and everything. Made by Omega pacific, but they are 34grams and definately 25kn.
I know it is overkill for hammocks.. but that rating was recommended to me
in whitewater rescue school for freeing pinned canoes and kayaks, so thats
what I have carried.

Seeker - Would love to see what you have found in the 3/4oz range! That
would be awesome. Be sure to let us know if/when you should find out
where/what they were.

Turk
2007-01-16, 19:52
funny thing about backcountry....
they really need to update product info.
http://www.backcountrygear.com/catalog/climbdetail.cfm/WC2040
http://www.backcountrygear.com/catalog/climbdetail.cfm/TRN161
claim that both those biners are the lightest full size in the world.


anyways, think I will look around for these...
http://www.backcountrygear.com/catalog/climbdetail.cfm/CMP450
28grams for a full size biner. and the same price as I paid for the omega pacifics
Not bad at all.

Take-a-knee
2007-01-16, 20:05
Those carabiner ratings are for a catastrophic failure, a fall with much less force could render it unusable by damaging/deforming the gate. Years ago, many carabiners wouldn't open with a man's weight on them, I don't think that is the case anymore. Metallurgy has come far in my lifetime.

TeeDee
2007-01-16, 21:42
Turk - try Amazon:

http://www.amazon.com/C-M-P-USA-Nano-Wire/dp/B000A3WGUO/sr=8-1/qid=1168997981/ref=sr_1_1/102-9390503-1856153?ie=UTF8&s=sporting-goods

at $6.29 - that's the best price for that class of carabiner I've ever seen.

At 1.6 oz for two, that makes the double ring buckle suspension with carabiner about the strongest and lightest I've seen.

Turk
2007-01-16, 23:31
awesome. thanks.

Just Jeff
2007-01-17, 19:56
So I'm convinced. I ordered 4 descending rings and 2 of these biners last night. Might have yet another buckle system to test...dernit!

TeeDee
2007-01-17, 21:21
A word on the double ring buckles.

They are like the cam buckles - they do not work or work well on thick or stiff webbing. Make sure the webbing you use is flexible. I bought some cam buckles from one web site to use with their webbing. Wanted to use their cam buckles since they tested and rated them at 900 lbs. Tried using their webbing with the cam buckles. The webbing was pretty thick and real stiff. It just zipped through the cam buckles under load - sounded like a buzz saw. They stood behind their buckles though and told me to return them and they refunded the original postage and the return postage. I'd patronize them again if I needed what they sell.

So with the double ring buckles, you can use practically any webbing - nylon, polyester, etc. - just make sure it is flexible. If too stiff, it holds the rings apart and then slips through. I can recommend the straps I use from Harbor freight, it is flexible and strong. Polyester.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=40063

and the price is good too.

TeeDee
2007-01-20, 21:56
Took the webbing with 2 rings and Velco cable wrap (I wrap around to keep it organized) to the Post Office today.

3.4 oz - webbing, double rings and velco cable wrap

3.3 oz without velco cable wrap

So with the Neutrino carabiner, that comes to 4.57 oz per end or 9.14 oz total or 9.34 oz with cable wraps.

Using the nano wire carabiners it would be 4.1 oz per end, 8.2 oz both ends and 8.5 oz with cable wraps.

Either way, not too bad.

Just Jeff
2007-02-08, 00:40
Posted this project on my page: http://www.tothewoods.net/HomemadeGearRingBuckleSupports.html

Good stuff...glad you guys convinced me to try it!

Rifleman
2007-02-08, 01:09
Convenient. I wonder How this system would behave in an all night downpour?
R.

Just Jeff
2007-02-08, 01:46
Haven't tested that yet. I think the rings would act as an isolator to make the water drip down, but that's just a guess. But with the cord near the hammock, I could put a drip string on that if the water makes it past the rings. That would keep the water off the hammock.

The water could decrease the friction and make it slip too, I guess. There's quite a bit of pressure on it when occupied, though...not sure if it would slip or not. Guess I should get out the hose soon!

If it started slipping in the field, I could just take off the buckles and use the webbing. That's why I'm still using full-length webbing at this point (I think these ones are 9'). Once I get a better feel for how it works and what length I need, I think I can get by with 6' max.

Good issue to test, though...thanks for pointing it out.

TeeDee
2007-02-08, 18:32
Two points about the double ring buckle:

1. Found another source for rings. These are Stainless Steel. 1 1" diameter for 1" webbing weighs as much as 2 of the AL descending rings. Disadvantage: weight. Advantage: size. 1" diameter vs. 1.5" for the AL descending rings. Web site: Annapolis Performance Sailing (A good source for cord and rope also)

http://www.apsltd.com

The rings are listed here:

http://www.apsltd.com/Tree/d3000/e814.asp

The 1" SS rings are rated at 1430 lbs working load, breaking load 4400 lbs, so should work for the suspension. I have 4 on order along with some rope I ordered. I am pretty sure I will stick with the descending rings, but want to try the SS.

2. Releasing the double ring buckles can get tricky. The cam locks were a lot easier to release. Found a real easy way to release the double ring buckles - as easy, if not easier, than the cam locks:

Think slipping a knot. To slip a knot to make it easy to untie, when you make the final tuck of the working end through the final loop, tuck a bight instead of the end of the cord/rope. Do the same with the double ring buckles - on the final tuck behind and under the bottom ring, tuck a bight instead of the end of the webbing. This accomplishes 2 things: 1. you don't have to thread the remainder of the webbing through, just the bight - if you use long webbing like I do to accommodate a lot of situations - I use 12' of webbing for each end, then you can have a LOT of webbing remaining, and 2. to release the buckle, just pull on the loose working end. That pulls the bight back through. I can pull the entire bight out and totally release the buckle or just pull a little to loosen.

No matter how tight the double ring buckle gets pulled, using a bight on the final tuck makes releasing the buckle very simple and very easy.

This change makes the double ring buckle easier for me to use than the cam locks were. Tucking the bight couldn't be done with the cam locks and I always had to thread the entire remaining webbing through the cam lock buckle. Tucking a bight on the double ring buckle means that I ALWAYS am threading the minimum of webbing - much, much quicker. Any other buckle I have reviewed such as the Crazy Creek buckles are like the cam locks - tucking a bight doesn't work.

Hope this helps others that are using or thinking of using the double ring buckle.

yuppie_redneck
2008-01-19, 01:59
I have finally decided to ditch the cam locks I used on the polyester webbing I use to hang my hammock. Didn't have any problems with them, but I continued to have 2 doubts:

1. I couldn't find the strength of the cam locks. The manufacturer cautions about exceeding 300 lbs. That did bother me even though I experienced no signs of failure whatsoever.

2. In releasing the cam locks in the morning, they are tight and the teeth grip and bite into the webbing. I was worried that the teeth on the cam lock could eventually abrade the webbing.

So I removed the cam locks and replaced each with 2 descending rings:

http://www.summithut.com/catalog/remap/product.asp/DeptID/327/SortOrder/1/pfid/14116/

These rings are very light - 2 weigh in at 0.8 oz. The webbing with 2 rings weighs a little over 3 oz. Will have to take to the post office to get a more accurate weight. That makes the suspension, including the Black Diamond Neutrino carabiners come out at about 4.5 oz for each end or 9 oz total. Maybe I could find lighter carabiners, but the Neutrino is the lightest that Black Diamond makes. I could replace the carabiners with bowlines and bring the total weight down by 2.5 oz, but I like the convenience of the carabiners and I'm not that obsessed with weight.

By sewing 2 rings into loops at the end of each webbing, I have a double ring buckle. The double ring buckle is as easy to use as the cam lock buckle (with the webbing at 1" width and the ID of the ring at 1.5", they are very easy to release, just pull the loose end to a right angle to the force on the webbing, simple). The double ring buckle tightens in the same manner as the cam lock buckles.

I don't think I have to worry about the rings abrading the webbing with the double ring buckle and I no longer have any lingering doubts about the strength of the buckle. With 2 of the descending rings holding the weight, the buckle is good for whatever load the hammock places on them. Also, I girth hitch the webbing around the tree and so have a double length of webbing from tree to hammock. Unless that is, the span between trees is too great and I have to run a single length. Haven't run into the situation yet. The webbing is rated by the manufacturer at 1,000 lbs, so even at a single length between tree and hammock, I should be okay.

I like the webbing for suspension - it acts as the tree hugger and suspension all in one.

Why not just use a simple prusik knot on each end? If I am being obtuse, please enlighten me, but a prusik is as strong as your rope, does not slide unless you want it to, holds in rain, and adds only the weight of another 12" or so of your rope. (at most)

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