Author Topic: Spong knot  (Read 4391 times)

xarax

  • Sr. Member
  • *****
  • Posts: 2781
Spong knot
« on: May 13, 2011, 11:13:50 PM »
    A  the very informative site maintained by Gary Storrick :
    http://storrick.cnc.net/VerticalDevicesPage/VerticalHome.shtml
    there is the picture, and a short comment, about a climbing knot I was not aware of, named "spong knot".
    http://storrick.cnc.net/VerticalDevicesPage/Ascender/KnotPages/KnotSpong.html
   (See attached picture). I think that this knot is quite interesting, and that it can be improved in a number of ways. Does anybody know anything more about it ?
« Last Edit: May 14, 2011, 12:54:03 AM by xarax »
This is not a knot.

DerekSmith

  • IGKT Member
  • Sr. Member
  • *****
  • Posts: 1518
  • Knot Botherer
    • ALbion Alliance
Re: Spong knot
« Reply #1 on: May 14, 2011, 01:26:33 PM »
What on earth does the back of the knot look like?

SS369

  • Global Moderator
  • Sr. Member
  • *****
  • Posts: 1775
Re: Spong knot
« Reply #2 on: May 14, 2011, 02:09:57 PM »
Hi Derek,

hopefully this drawing can help visualize the knot better and aid in the tying if necessary. It is an interesting knot that can work, though the users of prusik knots (spelunkers here mainly) state that it is unnecessarily difficult to tie. Many, including myself, resort to the basic prusik knot when tired and conditions are tough. But, it is good to know substitutes always.

Scott

xarax

  • Sr. Member
  • *****
  • Posts: 2781
Re: Spong knot
« Reply #3 on: May 14, 2011, 10:20:12 PM »
   What on earth does the back of the knot look like?
   Sorry, it was not my knot, or picture... :) When there is an ambiguity, I always post a "front view" and a "back view" picture of the knots I study and present. Thank you SS369.
   
   
 
This is not a knot.

Rrok007

  • Exp. Member
  • ****
  • Posts: 206
Re: Spong knot
« Reply #4 on: May 20, 2011, 05:51:07 PM »
Looks like a pretzelated cow hitch...

xarax

  • Sr. Member
  • *****
  • Posts: 2781
Re: Spong knot
« Reply #5 on: May 20, 2011, 09:12:09 PM »
   Thank you Rrok007

   Well, what was obvious to you was not obvious to me - obviously  :) . Although I had tried many modifications of this knot, I had never seen it as a derivative of a cow hitch  ! ( probably because I was thinking of modifications like the one tried on ABoK# 1740, at (1) ). Now , I have tried to do whatever has been done to the "parent" cow hitch on the upper side of the knot, on the lower side as well. It works!  A "symmetric spong knot", possibly easier to tie and inspect than the original one! Due to its simplicity/symmetry, this hitch should well be known already.

1) http://igkt.net/sm/index.php?topic=3016.0
« Last Edit: May 20, 2011, 09:14:49 PM by xarax »
This is not a knot.

xarax

  • Sr. Member
  • *****
  • Posts: 2781
Re: Spong knot
« Reply #6 on: May 21, 2011, 03:28:03 PM »
   The "anti-symmetric" version of the spong knot. This knot, just like the one in the previous post, is also easily inspected, and it works very well. ( No wonder, of course : see the functional similarity with the "ww" hitch, at (1) ). We can load/pull any one of the two (horizontal, orange) free ends, or both. All three ways seem to achieve adequate gripping power on the (vertical, white) main line, but I do not know which is better.

1. http://igkt.net/sm/index.php?PHPSESSID=cccb55c76f162ec461f0ff528d1386a4&topic=2849.0
This is not a knot.

Bob Thrun

  • Full Member
  • ***
  • Posts: 82
Re: Spong knot
« Reply #7 on: May 31, 2011, 05:41:09 AM »
SS369 shows the picture of the Spong from the May 1967 NSS News.  Here is the picture from Prusiking which shows how it is tied.  The Spong Knot grips around its own sling, which reduces the gripping force on the main rope and makes the sling hard to loosen.

« Last Edit: May 31, 2011, 06:09:08 AM by Bob Thrun »

Bob Thrun

  • Full Member
  • ***
  • Posts: 82
Re: Spong knot
« Reply #8 on: May 31, 2011, 05:48:27 AM »
I have not figured out how to attach more than one picture to a message.  The Symmetric Spong Knot posted by Xarax resembles the Gerard Hitch more than it resembles a Spong Knot.  This is from the 1929 Alpine Journal.
« Last Edit: May 31, 2011, 05:49:58 AM by Bob Thrun »

xarax

  • Sr. Member
  • *****
  • Posts: 2781
Re: Spong knot
« Reply #9 on: May 31, 2011, 06:44:08 AM »
   Thank you Bob Thurn,
   I wonder where do you find all those magazine texts and fine pictures from the Great-War, grand-mother era !  :)
   The two knots I have posted, as simple modifications of the spong knot, have something that is missing in the "Gerard hitch". They involve crossings - "cross garterings" ( of the coils on the main line, which is something resembling the "ww friction hitch", rather than the prussik hitch. It is an essential element of the parent spong knot, too. We have been discussing this the other day (1). Of course, only experiments will show us which of the two methods, the  prussik-like way  or the ww hitch way, offers the better grip on the main line.

1) http://igkt.net/sm/index.php?topic=2849.msg17369#msg17369
   
   
This is not a knot.