Experiment: "wrong rope weight" was almost completely due to humidity

Jim Tittwrote:

Garbage, the test is clearly defined and performed by the independent lab that certifies the rope. The results can be seen at any time by the relevant authorities.

The is no CE standard for measuring of a 50, 60, etc rope. There is a measurement for the g/m. There have been numerous times where companies give as much as 10% extra rope. 

If a company were to find shrinkage over time for a rope that they have been testing so add an extra 10% there is no guarantee that the people writing up the spec sheet will take this added length into account they may simply do 51g*length of the rope. 

There is also the fact that one meter as tested is slightly less than 1m of rope as you receive it. This was covered in an old thread. https://www.mountainproject.com/forum/topic/112241210/how-accurate-is-advertised-rope-weight?page=2

This is the most boring fucking thing ever and has been covered ad nauseum, I swear every few weeks there is yet another post about rope lengths and their weight. 

that guy named sebwrote:

The is no CE standard for measuring of a 50, 60, etc rope. 

Here is a list from UIAA site - https://theuiaa.org/safety/safety-standards/
Here is document pertinent to this thread - https://theuiaa.org/documents/safety-standards/101_UIAA_Ropes_V9_2019.pdf

But to clarify - are you getting upset that rope manufacturers chose to sell MORE than 60m rope in a 60m package?

amariuswrote:

Here is a list from UIAA site - https://theuiaa.org/safety/safety-standards/
Here is document pertinent to this thread - https://theuiaa.org/documents/safety-standards/101_UIAA_Ropes_V9_2019.pdf

But to clarify - are you getting upset that rope manufacturers chose to sell MORE than 60m rope in a 60m package?

Sorry I mistyped I meant to type, "There is no CE standard for measuring the weight of a 50, 60, etc rope."

I'm not remotely upset I'm just bored of people on here making posts about rope weights when no one ever takes into account all the many variables, usually implying there is some sort of malice and that the big bad rope company is trying to fudge the numbers. 

And just to prove a point, 

https://knowledge.ulprospector.com/1489/pe-dry-vs-conditioned-polyamide-nylon/#:~:text=Standard%20nylon%20materials%20are%20hygroscopic,faster%20nylon%20will%20absorb%20moisture.

One Google search and the first result tells me nylon will absorb up to 8% of its weight worth of water straight out of the air. The answer of water weight was obvious from the start and could be pretty much confirmed if you dig a little deeper, how much deeper? About 5 results down

https://www.researchgate.net/figure/Influence-of-Relative-Humidity-on-Water-Absorption-in-Non-Filled-Nylons-at-23C-in-air_tbl3_284257135

This is your periodic reminder that there is no obligation to respond to, or read, forum threads that you don’t find interesting.

Sometimes people want to discuss their experience or feelings. Maybe it mirrors someone else’s discussion; it doesn’t matter, they still have the right to discuss it. 

that guy named sebwrote:

The is no CE standard for measuring of a 50, 60, etc rope. There is a measurement for the g/m. There have been numerous times where companies give as much as 10% extra rope. 

If a company were to find shrinkage over time for a rope that they have been testing so add an extra 10% there is no guarantee that the people writing up the spec sheet will take this added length into account they may simply do 51g*length of the rope. 

There is also the fact that one meter as tested is slightly less than 1m of rope as you receive it. This was covered in an old thread. https://www.mountainproject.com/forum/topic/112241210/how-accurate-is-advertised-rope-weight?page=2

This is the most boring fucking thing ever and has been covered ad nauseum, I swear every few weeks there is yet another post about rope lengths and their weight. 

Again you are writing drivel, both rope length measurement and weight are clearly defined and what is legally required to be given. That they then change is an experiental thing that one has to live with, buy some clothing and use/wash it for ten years and report back.

that guy named sebwrote:

This is the most boring fucking thing ever and has been covered ad nauseum, I swear every few weeks there is yet another post about rope lengths and their weight. 

Agreed, so boring. Thanks for replying to the post FOUR times to remind us. 

I decided to make this work to my advantage. I'd been going into the sauna in the gym and had been successful in merely coughing as someone entered, as if I was dying. That was successful in clearing out the place, and I was happily taking saunas by myself for quite sometime. As fear of dying of covid wore off, all I would get in response to my near death dying coughing act was disdainful looks. 

The rope idea was brilliant and I thank you all for that. I took some into the sauna to see if the pre-weight was same-same as the after weight.  Of course I shook out a couple of loops to increase the surface area and thus the water absorption rate as is noted upthread, and the results were remarkably better than the hack a thon I'd been doing earlier. Women - in particular, would step in, look into my eyes, and then at the loose rope in my hands, and walk right back out. Dudes as well although they would give a few more seconds eyeball before they'd book back out. I didn't make nooses or anything. People are crazy.... and fearful.

I cannot tell you my joy at still having the sauna to myself. Those slackers who were earlier eyeing me derisively when I coughed, and refused to leave, were seriously eyes wide/head cocked and out the door when they walked in and eyeballed me with arms full of rope. 

Glad I have the sauna to myself again, and to this day can't tell you the weight of a climbing rope. Lets leave the adjectives like "drivel" and "boring" out of this discourse shall we?

steve barrattwrote:

This has been discussed here before, but some ropes come out way heavier than their specifications, even if you take into account the manufacturer supplying an extra length %. 

The actual weight (as opposed to listed diameter) is a pretty good predictor of some characteristics and a nice way to compare ropes of a similar class between manufacturers. Sometimes, we're actually going to want ropes that are genuinely light too. I get that its not that important for everyone.. that's okay. I don't care that much about my cragging ropes weight either.

I'm a bit annoyed as I just got a new Mammut 8.7mm single rope which I wanted to be as light as possible for mixed free- and rope-soloing on big routes. It was supposed to be 51g/m but the actual weight, if you don't make any allowance for over-length is about 54.9g/m. Its about 7% difference, but what is more annoying is that it's basically a rope more comparable to others of a different class.

I can't see any reason why manufacturers will sort out this unless there is a little accountability. Maybe some manufacturers have more consistent manufacturing than others? It would at least be good to know the real weights of some of the ropes to help choosing the model I want. 

The point of this thread is to start a record of real rope weights, to help use make better purchasing decisions. Also it may help to vent, or commiserate!

To kick things off:

EDIT: My rope as it came:

Mammut 8.7 Alpine Sender Dry* (60m, not measured, 3292g) should be 51g/m, actually ~54.9g/m (Not accounting for any over-length %)

EDIT: See post below.... it really is 51g/m

... stoked to be wrong :)

That’s a half pound difference, sounds negligible.

I just found this thread after weighing a new rope that felt kinda heavy (as well as some old ones).

New: Edelweiss Performance Supereverdry 9.2. Weighed at 59g/m. Listed at 52g/m. It was more confusing that when I received the package, the label said 57g/m. That‘s like one more pound that my middle-aged fattening body is annoyed with.

Newish: Edelrid Swift Protect Pro Dry 8.9 70m. Weighed 58g/m. Listed 53g/m.

Old: Bluewater Hyalite 9.4 70m. Weighed 58g/m. Listed 55g/m.

Dunno if these things “matter” or if I “care” a lot, but I do share some annoyance with the OP. (Note: It’s 15% humidity in Denver at time of weigh and I think I’m good at maths haha)

Dynamic rope length is dynamic