The magic of 7/64" amsteel...

[MrCrumbles]

... - is there any?
Whoopies and whatnot for suspensions etc is found in abundance when looking through what vendors offer, even 1/8” thickness. Now, I am looking into making suspension etc myself, I get it the way I want and I appreciate that.

So, looking at this for example I get a thinner and lighter line that also takes care of ridge line, tarp lines etc, all w the same line. It takes 1000lb load, that is a theoretical 2000Ib suspension so it will hold up.

Seems to be no problem w splicing etc, can probably even go down in diameter and everything will be hunky dorey - so why this love for amsteel 7/64”? Something I am missing? Otherwise I get my 100ft roll for 20$ and make virtually all the lines needed. Cheaper and consistent over all kinds of lines, I see no drawback, right?

Please advice.

[TominMN]

Just a couple of things. First, 1000lbs doesn't get doubled in hammock suspension. At a 30 degree hang angle, the theoretical weight that this cordage can support is 1000lb, not 2000lbs. Second, as soon as you subject the cordage to a sharp bend, including knots, the number decreases rapidly. Even most splicing weakens things. Then you want to factor in a safety margin: a multiple of the tested weight limit. FWIW, 7/64" Amsteel is only 1/32" greater than 2mm. The description of that cordage includes mention of dye. UHMWPE cordage is coated, not dyed. Coating can matter but, frankly, I don't think that's a huge deal with hammocking stuff. A discussion of coatings is a whole separate chapter.

Various folks have hung on small cordage, but it carries a risk. As you often see here, HYOH!

P.S. 2mm line is overkill for the tarp stuff. Even 1.7 is in terms of strength, but it's appeal is size, weight, and the ability to splice.

[MrCrumbles]

It is quite right w angles and forces. Theoretically you can hang the suspensions from right above your head in a beam or the like closing in on the 2000lb, on top of that the breaking weight of 1000lb for the cord is the bare minimum and it shoots over that in the normal case. Yes, knots etc will lower the limits but the point is still the same - weight wise that cord hold well and beyond what is needed in the normal case and it will take quite some bouncing around in the hammock too (no?) And that leads us to the last point - is the cord the weakest link? (Looking at you hammock, taking 1 ton of load on one bare layer of fabric)

2mm is thinner and thus not as resistant to abrasion/cuts/what have you, but would that actually be a problem people would hang in an anchor cable. Ok, exaggeration but would it be a known issue people would change whoopies every 100 nights or once a year or use some other limit of security, is that the normal case?

So, why this voodoo around 7/64" amsteel? My guess is just that - voodoo. There is still no good argument except for abrasion, cuts etc which is not much of an argument afaics. Even if it was 100% thicker than the 2mm cord will it be something that sticks w the kit for 100% longer time, what are really the practical implications?

Is 2mm overkill for tarp lines? Probably, but so is also fire wire or fishing lines alike talking about breaking weights. They are a menace to handle but that is a different thing. I can still buy my roll w one kind of cord and use it for all purposes hammock, save myself the money, hassle and whatnot for how many different dimensions of cord needed? 4m of 1,x mm, 2 of 1.y mm and 9 of 2.z mm, sir? May I suggest also some q mm, sir? No, one roll of this, thank you.

Weight? just guessing, what is lost on thicker tarp lines are probably not all won on the thinner suspension but how much more? UL-kit, sure, every nth of a gram counts (nothing wrong with gram hunters, they drive alot of eqp-think forwards). Here IS a reasonable argument against a thinner cord but it doesn't demystify the 7/64" amsteel religion.

So, still the question stands - what is the magic w 7/64”? My guess is just tradition and most arguments are postulate. Please convince me otherwise.

[ScottS]

I would venture to guess it has to do with the ease of working with it.

[nanok]

it would appear nobody can convince you otherwise, at this point, so i won't try.

for other people reading this thread : for supporting live humans (aka critical applications) the rule of thumb is a minimum of 5 times factor of safety to the expected maximum load. for hammocks, this means a minimum, for each suspension line, of 2x2x5xweight_of_monkey_in_hammock, if you want to be thorough. (2 because hangs where the angle is much less than the ideal 30 degrees are very common, 2 because the monkey moves, so will put some shock into the system, and 2g is not unreasonable). if one wants to be stingy, one might say 2x5, but that's as low as i would ever go.

now, if you have a customer weighing 40kg you can make a custom setup with 2mm dyneema throwline and such which is perfectly safe (and looks absurdly impossible), but would only be usable safely by that customer, alone. for general purpose, it is reasonable to assume about 100kg load in the hammock, and go from there. i suppose that's what most manufacturers do, and then 7/64 or about 3mm is the magic range with dyneema. it is also quite unconfortable to deal with lines much inder 3mm by hand, even when it is not cold out, so it makes little sense to cut corners in this case.

hyoh and so on, but please don't try to convince others of things which are obviously and unnecessarily unsafe. have fun.

[joe_guilbeau]

It's like the five blind wise men and the elephant... ie - Perception Shapes Reality

[Phantom Grappler]

The proof is in the pudding
Or if your choice of suspension works for you, then it works for you.
I have seven grandchildren, no telling what would happen if half of them jumped in my hammock.

I’m a cautious worry wart—I’ve chosen to use 1/8 inch amsteel in some of my suspensions, and some have 7/64 inch amsteel.

7/64 is a widely used size. There is something to be said for wisdom of the herd. But I see no reason for you to scrap your rope, until and unless it fails during use.

Good luck, join in on all topics hammocks!

[MrCrumbles]

it would appear nobody can convince you otherwise, at this point, so i won't try.

It is unfortunate you see it that way. I am merely questioning rules that I don't find reasonable explanation to. Be that sound or not. But blindly accepting a stated fact is seldom sound, whatever the fact. If you have arguments stronger than my hypothesis my hypothesis falls and I now understand the world better than I did before and no one is more grateful for that than me. Thank you.

for other people reading this thread : for supporting live humans (aka critical applications) the rule of thumb is a minimum of 5 times factor of safety to the expected maximum load. for hammocks, this means a minimum, for each suspension line, of 2x2x5xweight_of_monkey_in_hammock, if you want to be thorough. (2 because hangs where the angle is much less than the ideal 30 degrees are very common, 2 because the monkey moves, so will put some shock into the system, and 2g is not unreasonable). if one wants to be stingy, one might say 2x5, but that's as low as i would ever go.

See, a rationale and heuristics on top of that. The equation is a tad nebulous and the "5" seems not totally arbitrary but rather a 'better safe than sorry'-figure. Nothing wrong with that, levels of significance are, in the end 'this works in the general case, usually'.

now, if you have a customer weighing 40kg you can make a custom setup with 2mm dyneema throwline and such which is perfectly safe (and looks absurdly impossible), but would only be usable safely by that customer, alone. for general purpose, it is reasonable to assume about 100kg load in the hammock, and go from there. i suppose that's what most manufacturers do, and then 7/64 or about 3mm is the magic range with dyneema. /.../

And see, reasoning. Now let's check if I get the equation right from above, 2×2×5×100kg = ~3mm, and I think that the second figure 2 is grams (2g as per above). I am not entirely on the boat how the equation actually works but this has given me some input values when searching further. Thank you.

hyoh and so on, but please don't try to convince others of things which are obviously and unnecessarily unsafe. have fun.

I do not see where I am trying to convince others of anything. I see arguments of the kind "why X?" not "Do not use X because of..." (yeah, what?) Am I thought provoking? Mayhaps, but trying convincing anyone not using this or that - certainly not. Please note the last sentence of my second post "Please convince me otherwise", I am not trying to convince anyone, I rather ask people to convince me.

Your interpretation says I am trying to convince and that is fine by me, but argue for it then. Anyone can interpret the world so it fits their purposes, stand above it.

[MrCrumbles]

It's like the five blind wise men and the elephant... ie - Perception Shapes Reality

Good point. I fondle my part of the elephant and ask 'this is what I find - why is it like this?'
It might be what I find is right, it might not, but none the less I ask 'why is it so?' I have to verify AND try to falsify all the facts untill knowledge emerges.

Who do I ask? The wise men, and hopefully they have 'seen' more parts of the elephant than me. But accepting the answer 'Because it is' as The Truth? No. I'm rather fondling that elephant all over until I know my way around it. Whatever I understand in the end.

[TominMN]

You seem to have "convinced" yourself that 2mm is adequate. Many folks here have found that, over time, less than 7/64" (~2.8mm) just isn't worth the risk. It's not "magic." (It's also not rocket science or brain surgery!!!) I think the various responses are only trying to convince you that you may be wrong...

As far as using 2mm for the various tarp lines, it's worth considering that, if you're going to use UHMWPE cordage, it doesn't do well with knots. Hence the various bits of hardware that a number of folks use with 1.7. And, if you're possibly considering a one-piece tarp ridgeline with NAMA claws, 2mm isn't going to work. Folks who don't like to use hardware mostly shy away from UHMWPE cordage (except where splicing get the needed result.)