20220531, 08:03  #1 
Dec 2012
The Netherlands
5×353 Posts 
Knots, theory and practice
The mathematical theory of knots is fun.
So are many practical applications: sailing, climbing, surgery, ... Welcome to the knot thread! 
20220531, 08:04  #2 
Dec 2012
The Netherlands
3345_{8} Posts 
Is the round turn with 2 half hitches really a round turn with a granny knot?

20220601, 23:46  #3 
Aug 2002
3·2,837 Posts 

20220602, 12:48  #4 
Feb 2017
Nowhere
13550_{8} Posts 
I have gotten rid of many unwanted woody plants (small trees, etc) by cutting them down to short stumps, applying concentrated brush killer to the stump, and then covering the poisoned stump with a piece of plastic grocery bag secured with thin twine.
I had a problem in securing the plastic, however. A square knot, granny, or "shoelace knot" didn't work, because when I went to tie the second part of the knot, the string would loosen around the stump. It's similar to the problem in tying a ribbon around a package, which is sometimes solved by having a second person put a finger on the first part of the knot to hold it flush to the package. It finally occurred to me to do what I'd seen someone do on TV when they were tying up a roast or trussing poultry  use multiple twists instead of a simple overhand knot for the first part of the knot. That creates more friction, so when you cinch the loop up tight, it stays put while you tie a second overhand to secure it. It turns out that this is a wellknown knot, called a "surgeon's knot." 
20220602, 13:36  #5 
"Ed Hall"
Dec 2009
Adirondack Mtns
1001100101111_{2} Posts 
I commonly use a variation of the bowline  I go around the tree in the opposite direction, such that the loose end is on the outside. At a knotdisplay with knowledgeable presenters, I asked about my variation and was told it wasn't a recognized knot and therefore had no name. I told him perhaps it could be named for me. Later, I was told it was a named knot, for some country  maybe Norway  but, I haven't ever found it in documentation. Perhaps someone here knows more about it? I have found it to be just as effective as the standard bowline, but wonder if the loose end being on the outside has some disadvantage.

20220602, 20:45  #6  
Dec 2012
The Netherlands
5×353 Posts 
Quote:


20220602, 21:52  #7  
"Ed Hall"
Dec 2009
Adirondack Mtns
3×1,637 Posts 
Quote:


20220602, 23:13  #8 
If I May
"Chris Halsall"
Sep 2002
Barbados
13×821 Posts 

20220603, 01:33  #9 
2,833 Posts 
I was in trained in mountain combat ..Corsica, Pyrenees, Alps..and then some amphibious stuff where you needed to be quick and be able to make the required knots regardless of temperature or environment. This not quite a knot but if you wrap a rope around your body in a certain way you can rappel down "something" safely..but you may have a few rope burns at the end of it.

20220603, 03:33  #10 
If I May
"Chris Halsall"
Sep 2002
Barbados
13·821 Posts 

20220603, 21:33  #11 
If I May
"Chris Halsall"
Sep 2002
Barbados
13·821 Posts 
Sorry, Nick. I might have derailed your thread attempting to be funny... I'm going to try to work on that.
I understand that the maths behind knots is *seriously* deep. And, not yet fully explored. Those who use knots in the practical domain might enjoy learning from those who actually understand what they're doing. I know I will... 8) 
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