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.
A good way to join flat webbing is to tie a simple thumb knot in one end
(avoiding any unnecessary twists) and then thread the other end back
into the same knot. This gives two interlocking thumb knots with both
webs in flat contact all the way through. AFAIK it's still an approved
method for rock-climbing.
The other obvious precaution to prevent a knot from twisting out of
shape or coming apart is to leave a long tail, and then tie it down with
either an extra half-hitch or plain old electrical tape.
None of these knots are easy-release. If there really was such a thing
as an easy-release knot that you can also bet your life on, would
anybody have bothered to invent the karabiner?
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
Professionally:
IFW Technical Services Clear technical English - world-wide.
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: K7LXC@contesting.com
Sponsored by Akorn Access, Inc & KM9P
|