101–110 of 139 posts
I should learn more knots, but I so seldom need any. I look it up, generally get confused by the diagram, eventually work through it, and then forget it. I joined two pieces of rope last year and secured one tarp. I've tied up laces on my shoes a few times last year too.
I have a knot problem that I think pretty much everyone has encountered. How do you tie a bundle of branches or a cardboard box or something compressible as tightly as possible? The first way everyone tries is to cross the rope like you would for shoelaces, then putting pressure on the crossed rope with your finger, and trying to cross the ends of the rope with your one free hand to finish the knot. Inevitably the kn…
I have a knot problem that I think pretty much everyone has encountered. How do you tie a bundle of branches or a cardboard box or something compressible as tightly as possible? The first way everyone tries is to cross the rope like you would for shoelaces, then putting pressure on the crossed rope with your finger, and trying to cross the ends of the rope with your one free hand to finish the knot. Inevitably the kn…
Earlier quoted context omitted.
2. False. (Double) overhand aka euro death knot is superior for joining two ends of rappel line due to its smaller profile - lower probably of getting jammed on pull
Don't solo overhand knots significantly weaken the cord they're tied into?
Rappel only exerts a force equivalent to your weight, plus a little extra because of bouncing that naturally occurs during descent. 1kN = 224lbs force, so if you weigh 200lbs you can expect to exert about 1kN of force on a static rope. About the weakest static rope people frequently rappel on is a 7mm line, and a typical one[1] is rated to 12.4kN. So abrasion, knots coming undone, losing control of the brake strand, etc. are much larger concerns than static rope breaking due to knots.
Static ropes are ideal for rappelling, but climbers will often use the same rope they lead climb on to rappel on, and for lead climbing applications your rope must be dynamic. The weakest ropes you would usually lead on would be something like 7.5mm half ropes. A typical example[2] doesn't list a maximum breaking strength, because this statistic isn't relevant for dynamic rope. The purpose of a dynamic rope is absorb force during a fall: if you take a lead fall on a static rope, it's unlikely that the static rope will break, but hitting the end of a static rope is just as bad as hitting the ground with the same force. When you hit the end of a dynamic rope, it stretches to absorb this force, giving you a gentle fall. The maximum force on the rope listed is 9.9kN, which is from a UIAA-standard test fall: these falls are far more violent than anything you are likely to experience in actual usage. Ostensibly the rope can handle more force than that, but 9.9kN of force would probably kill you anyway. Luckily the rope stretch means it's unlikely you'd get anywhere near that level of force: a typical lead fall is in the range of 2kN. So again with dynamic rope, margins of error are very high, and abrasion, knots coming undone, losing control of the brake strand, etc. are much larger concerns than static rope breaking due to knots.
This is all fine and good on paper and in a lab, but does it work in the real world? The answer is yes: real world accident statistics[3] indicate that the most common accidents on rappel are simply rappelling off the ends of your rope. I wasn't able to find a single accident caused by rope breaking due to knots. Ropes do break, but this is typically attributed to abrasion over sharp surfaces, or long-term wear, and even these accidents are rare.
[1] https://sterlingrope.com/store/climb/cordage/tag-lines/7mm-t...
[2] https://www.mammut.com/us/en/p/2010-02762-11190/75-twilight-...
[3] http://publications.americanalpineclub.org/about_accidents
EDIT: Just to be clear, although there is a correlation between thickness and strength, the thinnest ropes aren't necessarily the weakest. The examples I give are examples of some of the weakest ropes I have used. This also shouldn't be perceived as a criticism of these ropes: as I said, these are more than strong enough. Thin ropes are certainly more susceptible to abrasion and aren't as durable, but this is a tradeoff for having a very light rope for moving fast. I used these ropes because they are the best ropes for the situations I planned for.
Earlier quoted context omitted.
Other than aesthetics (and perhaps as a hobby) are there circumstances in which cable lacing would be preferable to cable ties?
Cable ties / zip ties are often better when you need to change the configuration of wires (cutting the zip tie, moving the wires around, and setting new ties up). Zip ties are more prone to overtightening, but as long as you are aware of the overtightening problem, there's probably no real reason to avoid them. The main advantage of knowing cable lacing is that it generalizes. There are many long-objects that benefit…
My favorite, as many others are sharing here, is the figure 8. For climbing, it's a super versatile knot and there's lots of variations for specific use cases. It's also a great knot for discussing the properties of a good knot. I also have found the trucker's hitch really useful from time to time. It allows you to tie down a load, for example a kayak on top of a car. You tie the initial hitch, and then you get to cr…
The trucker's knot is awesome. Hugely practical. I use that knot on every load. https://www.animatedknots.com/truckers-hitch-knot
and? Wheres the research data and test results? or are we just supposed to take you at your word?
While I figure this is some passed down knowledge, i have always wondered if this was semi-true. Square knots are terrible.