Hi, this is my first post. I've been hanging around the forum for a while and have learned a lot. However, I have some questions I'm not finding answers to.
I'm in the process of building my first DIY hammock and am planning on using Amsteel blue for a structural ridge line. My first thought was to do a continual using something like a clove hitch or butterfly to tie off on the ends of the hammock. In researching what type of knot would work best I ran into some info that is making me wonder if Amsteel is the best thing out there for this type of application.
In my research I found that as a rule of thumb a knot will reduce the strength of a rope by 50% but specific knots may be more efficient maintaining upwards of 70% strength. The caveat is that these tests are generally done in nylon kernmantal ropes and it would seem that material and construction significantly effects toleration of knots. Some of the data I saw indicated that Amsteel may break as low as 30% with knots.
I'm thinking this weakening seams to come from the difference in the bend radius between required with different ropes. It states here http://www.sailingservices.com/catal...02009%2029.pdf that nylon rope needs a radius 3 times the diameter for the bend with 4 being ideal. However when you look here http://www.samsonrope.com/site_files...Retirement.pdf it would seem you need an 8:1 bend. The one thing I'm not sure about though is that is listed as a rotating sheave block and only 3:1 for a fixed pin termination.
So, the question is where is the correlation between the theoretical data and real life application. What is the breading strength of a larks head on the end of a woopie? Is it only 30% of the 1600 lb of 7/64 giving me 480 lb, which is only about twice my weight which isn't much wiggle room.
The next question would be, if bend radius is an issue would putting a nylon cover on the knot portion of the rope make a difference? This would take it from a 2:1 to a 3or4:1.
I hope I've been clear in what I am trying to figure out. Also does it even makes a difference?