Backup Knots

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How important is it to use an overhand backup knot with the tail of rope after you have tied into your harness using a figure eight follow through knot? Have there been any recorded accidents of a correctly tied and dressed figure eight follow through comming undone under load? I have heard climbers express their opinion that a backup knot just uses up extra rope that may be needed on a full length pitch and that it really only provides psychological insurance.

-- Brian Tryba (tbrian11@uswest.net), April 02, 2002

Answers

I agree with the previous poster. However if you use a bowline, the backup knot is very important.

-- Q.-Tuan Luong (luong@ai.sri.com), May 09, 2002.

It is not very important. What is important, however, is that you have several inches of rope(tail) after the figure eight is tied. Theorotically, if there is not enough tail, the knot could come untied as the figure eight cinches up on itself when it holds a fall.

-- Ronnie Miller (climnron@aol.com), April 04, 2002.

I agree with both posters above- it is an integral part of the bowline but unimportant for the figure 8, just ensure there are several inches of free rope coming out of the 8. Then again, it may have some psychologial value to a small number of climbers :)

-- Jeff Lam (jlam@earthling.net), June 08, 2002.

Backup knots are something i still havn't made my mind up on.

The figure-8 knot has a built in backup in it. If the last trace of the knot comes out, the knot stays just about as strong as when fully tied. It only loses some strength because there is a sharper bend in the rope at the top of the knot as part of the knot only wraps around a single strand of rope instead of two strands (the way it was originally tied.)

If this last strand comes out i'd re-tie it as soon as possible, but i wouldn't piss my pants over it either. You'll be safe, just make sure to fix it ASAP.

If you want to tie a fishermans backup on your tie in knot go right ahead. I usually do too. It only takes a few more seconds and you have a backup on your backup.

For any of you crazy sport climbers that tie in with a Bowline, always use a backup knot. The bowline can untie it self easily when its tugged around. The easiest and safest backup on this knot is the Yosimite backup (wraping the tail around part of your tie in loop and tracing the climb strand back up, so it looks more like a Figure 8) or just doing a 2 or 3 wrap fishermans below the knot on your tie in loop.

The bowline is a weaker knot, and i'm not about to go using it to tie in anytime soon, but it is easier to untie after a big whipper. So a lot of sport climbers use it. I'd say find out the numbers on the strength tests on each of these knots, then make your decision on which to use.

-- Jim Davis (jmdavis384@aol.com), January 05, 2003.


Try a "double bowline". The rabbit hole loop is doubled and the rest of the knot is the same. More secure but still releases after a fall. Still suggest backup.

-- Bill Betts (bbetts@shaw.ca), February 12, 2004.


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