Author Topic: Catastrophic failure of Double Overhand Stopper  (Read 12791 times)

Lexando

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Re: Catastrophic failure of Double Overhand Stopper
« Reply #15 on: February 19, 2014, 06:09:36 PM »
So... I came up with a solution: The double overhand stopper does fail in the extreme case of the upper E string so I invented a new(?) knot 8)

See http://igkt.net/sm/index.php?topic=4797.0 for details.

Lexando

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Re: Catastrophic failure of Double Overhand Stopper
« Reply #16 on: July 31, 2016, 07:32:44 PM »
The above solution is flawed and broke after 11 months.

The weakness is in the first turn.

A better solution is a simple modification of the double overhand.

See: http://igkt.net/sm/index.php?topic=5724.0

Twine

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Re: Catastrophic failure of Double Overhand Stopper
« Reply #17 on: August 01, 2016, 02:07:40 PM »
Very neat! Easy to remember and tie. I just tied your guitar bead stopper in thin braided nylon string, and it formed a rock hard knot that I couldn't untie, so it should probably be used only for permanent attachments just like what you are doing, tying beads to guitar strings. It turned out to be self-dressing, too, so it's quicker and easier to tie than Ashley's stopper. Congratulations on finding this neat solution! I hope it doesn't weaken the string too much. It has many turns so maybe it shouldn't, but it still would be nice to see it tested and compared to Ashley's stopper.
"Simplicity is the ultimate sophistication" - Leonardo da Vinci

SS369

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Re: Catastrophic failure of Double Overhand Stopper
« Reply #18 on: August 01, 2016, 02:23:00 PM »
Good day Lexando.

Getting the line into the body of the knot straight should help longevity and it made me think of another.
https://en.wikipedia.org/wiki/Heaving_line_knot

May not be as easy in the strings you are using, such little diameters!

FMI: How long are the strings "supposed" to last?

SS

Lexando

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Re: Catastrophic failure of Double Overhand Stopper
« Reply #19 on: August 02, 2016, 04:36:49 PM »
@SS369, That first turn of the Heaving Line knot looks like it will have the same weakness as my original ugly solution. As you observe, the diameter of the top E string is very small and this gives rise to bending stress which is what causes it to fracture.

As for how long the strings are supposed to last, it depends on how much you play. Normally, not more than a few months although the upper three strings can outlast the lower three by as much as 4x because they are simply monofilament and non-corroding. The lowest 5 strings on this guitar have been in place for more than a year and you can see degradation on the A & D strings in the photo.

@Twine, with reference to your sig, I knew a simple solution must exist. In my separate thread, purely about this knot http://igkt.net/sm/index.php?topic=5724.0 James Petersen identifies it with ABoK #1843, however, there it is only shown as an anchor bend.

SS369

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Re: Catastrophic failure of Double Overhand Stopper
« Reply #20 on: August 02, 2016, 09:52:33 PM »
@SS369, That first turn of the Heaving Line knot looks like it will have the same weakness as my original ugly solution. As you observe, the diameter of the top E string is very small and this gives rise to bending stress which is what causes it to fracture.

The line goes along straight through the body of the wrapping turns before it reaches the first turn as you can see in the tying sequence at the linked page and so it will have a sort of spring to press against in between the bead and the first turn.
Sort of works like "bone beads".

Perhaps not too many wrapping turns will help.
I have no string instruments to try this on, so, it is up to you or another musically gifted person to give it a go.

SS