[TowerTalk] double figure 8 bend

[Jim Lux]

It's pretty straightforward to join (bend?) two ropes together with the 
figure 8 style knot. Tie the 8 in the end of one, loosely.  Feed the other 
robe through to match the first, except coming in from the other end.  For 
more security, one can tie two 8s some distance apart. You can also put 
extra twists in the knot (the basic figure 8 is just an overhand knot with 
an extra twist). The stacked overhand is known as a "water knot" and is 
(used to be) used for making runners out of 1" tubular sling material or 
tieing your swami belt (showing my age here..).

One advantage of the doubled 8 is that it's fairly flat, so it doesn't snag 
as easily as the other big candidate for joining ropes

A modification of the overhand based bend, using a pair of overhands 
stacked is called a grapevine knot, and was popular for slinging chocks and 
hexes with round rope.  I suspect that modern fibers like Kevlar and 
Spectra and bombproof sewing has changed this a bit. 
(http://www.pacifier.com/~ies/grapevine.html)

Maybe searching for "double rope rappel" might turn up this technique.

At 02:43 PM 8/25/2003 -0700, Terry Dunlap wrote:
>All three of those sites show different versions of a double figure 8 and NONE
>of them illustrate it used for joining two ropes.
>
>73 de Terry KK6T
>
>
>
>At 04:14 PM 8/25/2003 -0400, Ted Sarah - W8TTS wrote:
>>Try these sites:
>>
>>http://www.chockstone.org/TechTips/BunnyEars.htm
>>http://www.artex.co.jp/Pages/outdoor/ropework/pages/r_DubleFigureEightKnot.html
>>http://www.realknots.com/knots/sloops.htm
>>
>>73 - Ted - W8TTS
>>
>>
>>Eric Scace K3NA wrote:
>>
>>>    A while back Ian G3SEK mentioned in a posting:
>>>"Darrel Van Buer wrote:
>>>
>>>>Climbers seem to prefer the double figure 8 bend - it's work to tie and
>>>>really hard to untie, but virtually nuke-proof as far as coming undone
>>>>accidentally.
>>>Absolutely - even in slick plastic rope after years of use, figure-of-
>>>eight knots still don't even think about coming loose. They have the
>>>advantages of a fairly straight pull out of the knot (minimizing loss of
>>>strength in the rope) combined with a lot of friction inside the knot. 
>>>Tied on a doubled-over end of rope, the figure-of-eight makes
>>>a very
>>>strong loop. To join two ropes, tie a loose figure-of-eight on one end;
>>>then thread the other rope into it from the opposite end, keeping
>>>parallel with the first rope to make a second interlocking figure-of-
>>>eight."
>>>    I've done a search for "double figure 8 bend" on the web and can't 
>>> find any other references to this knot.
>>>    From the description, it's possible that the description is a double 
>>> sheet bend or a knot variously known as a Carrick bend,
>>>Josephine knot, or anchor bend.  When tied correctly, this appears to be 
>>>a very highly regarded mechanism for joining two lines
>>>together temporarily.  However, it must be done correctly!
>>>    Can someone clarify?
>>>    Thanks.
>>>-- Eric K3NA
>>>
>>>_______________________________________________
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>>
>>
>>_______________________________________________
>>
>>See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless 
>>Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with 
>>any questions and ask for Sherman, W2FLA.
>>
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>
>_______________________________________________
>
>See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless 
>Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with 
>any questions and ask for Sherman, W2FLA.
>
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