Sailor skills. - KNOTS

Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
McDonald Brummel Splice
McDonald's quick Brummel splice for hollow braid rope. Putting a quick but secure eye in a length of dyneema or other HDPE line. The eye serves as a terminal end that you can use to secure the line, perhaps to a padeye with a soft shackle.

The knot is locked with a tapered long bury of the end tail.

Check out the detail for this knot on McDonald Brummel Splice
 
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Likes: jon hansen
May 17, 2004
5,032
Beneteau Oceanis 37 Havre de Grace
Nice. I’ve made the same splice a couple different ways -
And

The first technique is definitely the easiest, but it only works if you have access to both ends of the line. The second technique with the inversions is like magic when the new eye forms, but sometimes the inversions are hard to undo the right way. I’ll need to try @jssailem ‘s way for comparison.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
David. There are two important steps to the secure the knot.
  1. The tail must be 72 times the diameter of the line you are using
  2. The tail must be tapered
In testing the soft shackles I learned that the dyneema buried tail will break at the point of a square cut off end. If the tail is tapered the break strength is higher.
 
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Likes: Will Gilmore
May 17, 2004
5,032
Beneteau Oceanis 37 Havre de Grace
David. There are two important steps to the secure the knot.
  1. The tail must be 72 times the diameter of the line you are using
  2. The tail must be tapered
In testing the soft shackles I learned that the dyneema buried tail will break at the point of a square cut off end. If the tail is tapered the break strength is higher.
Definitely. I did make sure to have a long bury and a taper when I redid my Dyer Dhow rigging. It’s interesting that the weak point isn’t the spot where the line passes through itself in the Brummel. I guess that’s probably because the Brummel only helps lock the splice when it’s not under tension, the way the lock stitches do in Samson’s technique. Once under tension the bury is what takes all the force.
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
About a year ago, I load tested a dyneema soft shackle. The listed breaking strength was 8500. The test break occurred at 10,800. The bury was just cut off square. As the tension built, I observed the fibers bending at the cut ends as the line constricted over cut ends.
Here are images of the setup and the broken line. Note the breakdown did not happen at the knot. This shows that the former knot is not a weak spot.

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There was a bit of heat created in the process.
 
Oct 2, 2008
3,807
Pearson/ 530 Strafford, NH
The reason I know how to use this method is whether or not you have both ends of the line to work with. Splicing an eye on both ends of a line, for example.