Climbers, help me out here......Carabiner ratings.

I picked up a couple CAMP Nano 23, wiregate carabiners for hammock hanging. These little guys weigh 23 grams...almost nothing. They are rated at 20 kilo-newtons, which works out to 4,500 POUNDS!!!????? For $6 ?! I'm sorry, I have a hard time believing these cheezy little aluminum hooks can lift my Toyota 4Runner, complete with passengers.
Am I understanding this right?

I'm not certain, but I think that rating corresponds to weight during impact (during a fall, for instance), not for a constant load.

Dryer you can post a photo, but that sounds about right. The aluminum alloys they use combined with the shape makes for some pretty awesome devices. However the formula F=ma force = mass times acceleration is a sort of momentary thing (with acceleration as a variable) vs "holds 4500 pounds. It probably will hold 4500 pounds, (its the same amount of force) but thats not an important thing to climbers who are worried about impact. That said Camp produces junk, pardon me. Others will argue, but theres a reason why its $6.00. I have here a black diamond wired beener in my hand that says 24 kN along the axis, 7 kN perpendicular to the axis and 8 kN along the axis with the gate open. Ya see with the gate closed its essentially a ring.
Jim

Well, Jim, I can't disagree. I simply wanted the lightest thing available for my hammock hanging adventures and the Nano 23 is the lightest. I just can't see an engine block...or me...suspended from this little thing. It looked about the same quality as the other carabiners there.
http://www.rei.com/product/764094?preferredSku=7640940016&cm_mmc=cse_froogle-_-datafeed-_-product-_-7640940016&mr:trackingCode=7590071B-81F9-DE11-BAE3-0019B9C043EB&mr:referralID=NA

They will be fine. Of course, these ratings only apply to users who are pure of heart...I am sure there are no issues there, right?

I just purchased three carabiners of this same ultra-light type and I am surprised at their extreme light weight; these ultra light-weights look superficially like the various "toy" biners that (usually) are stamped on their sides "Do not use for climbing." Someday someone will confuse them and have a big problem.

The ratings you cite are UIAA ratings, derived from testing. The carabiners are in the REI product line, with those cited ratings. I am comfortable with that.

The company would probably really appreciate a picture of your Toyota and family hanging from their biner, provided the gas pedal doesn't malfunction on the way to the photo shoot.

Uh oh.

Hmm
my BD beener weighs 37 grams.

I was thinking in Newtons F=ma where a= acceleration defined as a change in velocity, which means speeding up, slowing down, or turning. "a" for a beener is actually the deceleration of the climber, but the velocity of the climber came from gravity. The acceleration from gravity is 32 feet per second squared. Weight = m x gravity which actually means weight F = m x acceleration, the acceleration of gravity (on the surface of the Earth) so the Force of a climber falling will exceed the force of his normal weight yet the F=ma equation is the same, so yes I would say it will hold your Toyota, but I wouldn't trust my Toyota to a product made by Camp, however if if has the UIAA rating then its what it is regardless of who makes it, but like I said, my Black Diamond wired beener which is ten years old weighs 37 grams.
Jim

Good stuff, Jim!
The CAMP Nano 23 is only for holding one suspension line of my hammock to make 1) a truckers hitch and 2) a place to clip my pack/shoes/etc. It will be holding a load maybe 1/10th it's rated limit. Having a carabiner or two in the pack ain't a bad idea either.
I've got beeners of various kinds for SAR work, mostly screw gate. I've used them for water work. Use them for my sailboat too...a meunters hitch as a jibe boom brake works really well.
I was just taken for surprise that a 23 gram aluminum hook could hold that much shock/weight! Also, comparing other wire gate beeners (i like your spelling), the designs are very different, especially with the spines. Some are "I" beam shaped, some are elliptical like the CAMP product.
So....what makes CAMP junk? What should I be looking for, quality wise? All my other beeners and descenders are BD and Petzl. CAMP makes the lightest of all.

The most important thing is that it keeps your rear end off the ground!

I have some and they haven't let me down yet!

Now, would I hang my truck from them? Nope.


Going out this weekend.


BTW Dryer, I was down at the top of the 4c last week scouting out the area. Will be doing a top-to-bottom in a couple of weeks if the weather cooperates.

Cheers!

Dryer,
perhaps I shouldn't run down Camp, but in the past they made very iffy "looking climbing gear" like aluminum headed ice axes and their aluminum crampons. Granted there is a market for this really light stuff, but my mount blanc airtech forged chrome moly head ice axe didn't weigh that much more than the aluminum headed one. ( also the rubber coated handle on the Airtech IS critical to keeping your hands from freezing and improves your grip when hanging on for dear life.)Perhaps for occasional use the camp unit might be the way to go especially for a weight fanatic, but you know me well enough to know that I demand the highest quality in equipment whose failure may cost you your life. If you've ever taken a major fall on ice and done a self arrest you would know what I mean, only a sharp tough axe will save my butt. Its like carrying a plastic avalanche shovel instead of a metal one, you can't actually dig in hard snow and ice with the plastic one.
just my $.02 worth.

So this brings up an interesting question. How much load is actually on the suspension lines of a hammock? The amount of sag in the lines makes a lot of difference. The weight distribution of the occupant, the total weight and distance between trees are also factors. Next dry day I'll get out the Hennessy and a load cell...

Occupants?

(For the so-comfortable-they-like-to-spoon members of the hammock mafia)

Eric,
its the angle of the dangle that matters. If the lines hung straight down the force would be equal to the occupants weigh, and if they are perfectly horizontal that value goes to infinity, so its a matter of trigonometry. Since most people tie their hammocks pretty tightly then lay in them there is a tremendous amount of force. Lets see you would divide the weight of the hammock and occupant by the sin of the depressed angle, that is the angle down from horizontal. 180 pound load with 45 degree angle = 180/.7071 = 255 pounds. 30 degrees is sin 30 = .5. 180/.5 = 300 pounds. sin 20 = .342 180/.342= 526 pounds. Now for Bigfoot with really tight lines and non-stretch ropes at say 10 degrees, sin = .1736 so 250/.1736 = 1440 pounds.
Jim

Jim,
I get the angle thing (old theatre rigger here) and that's my point. The angle will change under load since the whole thing is elastic. Small changes in length can cause large changes in angle and so load. Also there's impact loading as you move around. All that said, you're right "a tremendous amount of force".

It's tremendous, but not that tremendous. I hang my hammocks fairly loosly with the ridgeline sometimes luffing just enough to keep the netting off me. Maybe 250#'s on the ropes? However, one thing I'm about to do is change my suspension lines to Amsteel Blue to maybe shave few ounces off the pack weight. That stuff replaces wire rope on 4WD winches, pound per pound.

So, 4500 lbs. capacity for a .8 oz. aluminum beener, or a 3/8ths" threaded steel shackle at 2200lbs. and about 1 lb. weight. Oh, yeah, that makes sense!

I use "pretend" 'biners that I bought at Home Depot for 99 cents. Anodized Alu. 23grams. Been on my hammock for years, even my double. Never had a problem. I must have 20 of them on my dog leashes, keys and hammocks.

The rating is 150 pounds and they're stamped "not for climbing." I'm confident that they can hold much more than that. Long ago I worked in a materials testing lab were I pulled/loaded lots of jackstands, tow straps, etc. to failure. Most of those items withstood at least twice their rated strength.

Those things scare me. You realize they are "not for climbing," but I am waiting to hear about the accident where the toy biners get deployed in a load bearing situation and fail.

I think I would rather spend the coin for a stronger, more versatile gizmo.

Did you ever do any tests on climbing biners? The results would be interesting.

old ranger there are labs that do a lot of testing on climbing gear. Like they'll take down anchors that have been used for few years in climbing areas and pull them to destruction to see what real world does to gear.
http://www.xmission.com/~tmoyer/testing/
Jim

Boy, have I got a lot of gear they could test. I think I still have a Bedayn carabiner or two lurking around - just used to leash the dog - they have been retired from climbing for a decade or two.

The rain stopped so I did a little testing. Note: I'm 5' 11" and weigh 158#. I strung my Hennessy hammock between two trees 12' 6" apart with a Dynafor electronic load cell, set to record peak load, in the foot end suspension line. I tensioned the lines the way I usually do which is snug but not pulled tight. That measured 5" of sag. I then climbed in a bit less gently than a normally do and bounced around a little. The peak load was 180#. Then I pulled the suspension lines as tight as I could without resorting to a truckers hitch and climbed in again. Peak load 212#. I switched to trees 17' apart and and repeated the test. Peak load with a little sag 228# and pulled up tight 254#. Granted I'm not a worst-case test load but it looks like any device with a working load rating over 600# should be good for anyone. I think I would stay away from the "key ring" biners and dog clips.

Wow, you put a load cell on a hammock.

VERY good info Eric! I'm 5' 11' and 185ish, so I shoudn't max more than 250 lbs, loosly strung. Maybe I should offer other hammockers a 'tie on' on my new beener. It should hold about 15 of us.

Nice! That's actually nice to know, not only from a 'biner strength persepective but from a hammock lines perspective - especially when trying to sew something light but still not likely to leave you on your butt on the ground suddenly.

My first homemade hammock used para cord as the suspension lines. The weight rating on the cord package said 550 lbs. A test hang in the back yard dropped me flat on my back from about 18inches...just after I fell asleep! So, I don't trust paracord anymore. Any hammock suspension needs to be a quality product from a trusted maker, and a big margin for error. Not a place to skimp.

Thanks Eric
its always interesting to compare the theoretical to the measured. I guess for one thing you make sort of a banana shape not a triangle and I wonder what the angle of the dangle worked out to be in your tests. The measured forces should have been higher. Was you rope a stretch or non-stretch type?
Jim

Jim, when I first started hammocking, I used those pocket 'net' hammocks from Walmart. Those things need to be hung very tautly just to be able to lay anywhere near flat.
The ropes felt as tight as piano strings.
The newer 'assym' style hammocks don't need to be hung tightly at all, and my guess is, because you are laying diagonal to the rope axis (outside the triangle) you are able to get much steeper sides to your "triangle". To make the trig work, the angles need to be measured after the hammock is loaded and the intersection would be about where your butt is. Maybe a 70-80 deg. angle at the 'butt point', vs. 30-40 deg. with the old net hammocks. Your math is right....just have to figure out how to measure an 'assym' hammock.

Now, having marveled in the amazingness of super-light beeners, have a look at the load ratings of this stuff:
http://www.samsonrope.com/index.cfm?rope=192
(scroll down to the bottom for a chart)

The chart is impressive. Isn't this stuff a bit tricky to tie in knots (vis-a-vis splicing)?

Not really. It feels like soft ski rope and holds knots well.
It's hollow, so you can make slings and splices easily.
Yet again it will mess with your head....1/8" dia., 2500 lbs.???!!! I have a hard time trusting that.
Here's some splicing instructions:
http://www.samsonrope.com/index.cfm?page=28

This means that 7/64ths string could replace the Spectra on the Hennessey and save about 1 lb. That just doesn't sound right.

Jim, The rope is Spectra which doesn't stretch much but the hammock itself stretches quite a bit. I couldn't measure the angle of the suspension lines without a helper, which I didn't have.

Dryer
it may appear that that stuff takes traditional knots well, but considering the loads I suggest looking further if you want knots that are anywhere near the load strength, and be prepared to lose from 20% to 50 % of the load value if there is any kind of knot. The OLD carabiners were round and pretty big, the ropes going around them were not stressed too much, but the tiny new carabiners are thin and bending rope around them severely weakens it. So there is a major offset to the weight savings. I'll bet Camp doesn't mention that in their beener information. Personally I would use a triple or even quadruple fishemans knot, but please do not take this as tested advice. Go to the manufacturer for specific knot recommendations if you depend on those knots for your safety. I have some old Dolt rings which are circles about 1.5 inch OD and they have smoothly curved internal shape so that they are shaped like an old wide carabiner. They are immensely strong and were the preferred way of bending a rope around something besides a fat beener.
Heres a photo of two original Dolt rings which were either forged or milled from solid rod, and on the bottom is a modern hollow version of much smaller diameter which is rolled from a stamping. Obviously the old Dolt ring would be less destructive to the rope, but of course the modern one is cheaper, lighter and available. They are used to set up anchors where a triangle to two sets of bolts and one looped rope downward, carabiners CANNOT take a three angle load.


the lower center ring is the modern one, the other two are original Dolt rings made by Dolt, they must be from the 60s.
Jim

Agree...knots I know. That would be the one of a couple downsides of using really thin lines as suspension rope. As a line gets smaller, the mechanical advantage knot bends/loops produce on itself is huge. That certainly makes sense for hardware, too.
I'll typically wrap my suspension line 3-5 times around the tree, and tie off with a couple halfhitches. Fatter line also protects the tree if huggers aren't used, which I normally don't. My new beener is for use with hugger straps.

I'm going to be switching over from straps to the Amsteel Blue later this spring. It's not so much for the weight saving but rather for less bulk.

Right now I'm using the ring buckle suspension as described over on hammockforums.net.

I'll be switching to the Amsteel Blue and whoopie slings or perhaps some type of hybrid with the beeners and the Amsteel Blue 7/64ths.


Of course Paul, we'll want pictures of your set up.

Tim,
Mine is always going to be simple, minimalist. I rarely use a tree hugger strap....instead wrapping multiple raps of suspension line around the tree. No rings here, either. The beener is to allow for use of a truckers hitch (when using a hugger strap) and/or to hang my pack. Whoopie slings are interesting and I might go there someday. West Marine sells Amsteel Blue. It's nice see side by side comparisons of different lines.