i did get the green light to use the machine to test the tensile strength of the various bury lengths within a continuous loop configuration.
i plan to test 4 continuous loops for each bury length; will use 1", 2", 3", 4" bury lengths. if the data is too erratic i may consider increasing the sample size. the material being tested will be with mason line. i will try to get a controlled tension strength for the mason line as well. stand by for the results; it may be as much as 2 weeks.
CORRECTION:Originally Posted by gmcttr
The info for the third photo and the third photo are incorrect. To make what some call a locked brummel in a CL, the 'pass throughs' are not the same as in photo one. As has been mentioned (or alluded to) by others, the pass throughs would be done as if you were making a locked brummel in an eye splice and would look like this...
IMG_5160 (Medium).JPG
For an eye splice, the orange cut leg would be buried in the silver cut leg while for a CL the ends are folded back on themselves as in this photo and then buried into themselves...
IMG_5161 (Medium).JPG
Clear as mud?
So... now that that has been definitively cleared up... getting back to the original question: "What is the smallest continuous loop I can make out of amsteel blue and it be load bearing?" If people have been making loops using an eye splice and getting away with it could one say that it is possible but not advisable to make a continuous loop any size you want by using the eye splice? This would eliminate the minimum size which was previously determined by the bury.
Well using the locked method, all the load is taken by the lock. So it's technically not a splice, the bury is just cosmetic. I doubt Samson rope would endorse the method as a load bearing splice. If you are following their rules, then 8.5" is the recommended bury for 7/64 amsteel blue, so assuming overlapped buries are not allowed either, a loop with a 17" circumference (17/pi=5.4" dia) is going to be the smallest 'official' load bearing continuous loop you should make.
Can you get away with shorter loops - yes, I'm sure of it. You could probably get away with the locked method and cosmetic buries, which would allow for very small loops. You could probably make 2" dia loops that way and I bet they'd still be pretty darned strong. I know knots in amsteel drop the breaking strength to below 50%, but that's still more than paracord, and people get away with using that. Should you do it that way? Probably not, but it's your rig, you can make it how you want.
It's not an eye splice, it's still a CL and everyone still uses the same buries.
If you want to make tiny short CL's (with big lumps), don't splice. Use a double or triple fisherman's bend to join the ends.
http://www.animatedknots.com/doublef...Categ=climbing
...or you could make a really small soft shackle. You could make one with a 2" diameter and it would be just as strong as a big one.
I made these about 8 or 9 years ago for a skydiving project. They are bar-tacked at the burys, using a Pfaff 3334, with a 42 stitch, center start and stop cam.
image.jpg
Forgot to mention, these are made with 900 Dacron line. Very similar size to 7/64" Amsteel Blue.
I thank you all for this thread. I've been hanging on continuous loops for 2 years that I made wrong. Now I know. My bad loops have a real locked Brummell and that is really all I was hanging on--because my buries did not go across to the other side but they folded back into themselves or back into the side they came from instead of continuing on to the other side of the locked Brummell. I feel really stupid for making splicing errors on loops that hold me off the ground. I need to study this splicing more before I can assume I know what I'm doing. Thanks for the information, I would never have thought of it independently. Scared
Did anything ever come of this?
Thought I'd fan the fire, as I believe a couple of different questions remain unanswered and, I for one, what to know!
First, I would support the assertions that the pass-throughs (locked brummels or the other, shall we say "unlocked" brummels) add absolutely nothing to the ultimate strength of a spliced loop or eye. Of course, no one here is strong enough to pull a fixed brummel apart before the bury is done on a eye, but the force needed to do that is a fraction of what it would take to break that eye after the proper bury is completed.
FWIW, there actually IS a method of doing a locked Brummel on a CL but I dare anyone to be able to accomplish it with anything as small as even 1/8" amsteel!
But what would be the point of doing it anyway? I'm absolutely convinced that gmcttr's method of making CLs (no pass-throughs) is at least every bit as strong as those made with the pass-throughs. CLs typically don't come undone primarily because the buries are so close to one another that nothing pulls at the line between them to encourage separation and the milked outer section is essentially kept in place by being wrapped around an end gather or pulled through a channel, i.e. they are almost always under a tiny bit of load
To me the more intriguing point that was brought up earlier in this thread was the idea that only one of the buries in a CL need to be moderately long to achieve maximum CL strength. The other bury, supposedly, can be pretty short. Now THAT shortens up the overall circumference by a couple of inches from what I see.
So what then is the shortest CL of truly adequate strength?
Last edited by TominMN; 07-16-2015 at 05:30.
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