I think you should listen to engineering advice before basing on personal experience. <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />

There is no doubt that knots weaken lines. The best knot still weakens a line by 40%. Some of the worse knots weaken line by 60%. A double fisherman is a good knot that is closer to the 40% figure. I've read many scientific studies related to this. It's a fact.

Again though the failure point is usually a wear point in the line. Because after a line hits the real world you can throw all those scientific studies out the window as the real world is a very rough place.

Mike Hill

Jake,

Come on Jake, read what is actually written !

I never said knots didn't weaken lines, just that with care they weaken lines alot less then what is made out in this thread. Additionally I said splices weaken lines as well, often less then knots but nevertheless ...

Please don't make any strawman arguments of my comments.

Either that or content that I have mastered the oriental art of hovering weightlessly on my knotted trap lines that obviously can't support my weight ! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Not to mention the telekinetic attraction I excerted on my quiver of stunt kites in a good blow fitted with 100-150 kg break strength lines, dragging my 100 kg frame and clothing through the sand and air, plowing the beach.

There are several tricks to compensate for knot weakening. After a while I was only breaking the lines on the unknotted parts and never at or even near the knots themselves. These are not high tech tricks by the way, most of them are pretty much common sense.

If you are interested the combo of a piece of line with a bloodknot and a fishermans hitch on the main line was the superior setup of all. It could be dissembled very easily even after being highly tensioned and broke a lot less then any loop, spliced or unspliced around any ring or shackle. In fact it was the bend around the ring/shackle that weakened the line the most and even significantly more then the knots ever did. Shock loadings tend to do different things to lines then high static loadings. Loops or peices of line that changed shape or angle under shock loadings often failed on my stunt kites; the "static" knots themselves didn't.

I have the very same experience with traplines where the 5 mm (2000 kg break) running trap line breaks alot more often around the little pully then the 3 mm knotted traplines themselves (I have never broken one in 7 years).

But as with all things I write, make the best of my (real life tested) comments or simply ignore them are irrelevant based on an appreciation of my persona. In teh end, I don't care either way.

Wouter

I guess you just answered your own question.

Geezus, Stephen !

Are you trying to be dumb or it that your natural state of being ?

He is a brainbreaker for you;

if a knot is sufficient for the job then what is the advantage of a splice that is "more" sufficient ?

Neither won't break and I can tie that knot in 5 seconds or less in any given line.

I would like to see any-one make a splice in a (attractively priced) two-stage dyneema line with a very tightly woven mantle and an extremely open weave core. Let alone do it under 5 seconds. The line I used was 2.5 times less expensive then spliceable dyneema lines like D12 and swiftcord; it also creeps less because the is less "setting" of the fibres under load.

With respect to stunt kite lines, any takers for splicing a multi threaded slippery line with a outer diameter of 1 mm ? Bring your magnifying glass and diamond pincers.

There are jobs that call for splices and there are jobs that call for knots. With regard to traplines either method will work satisfactory. When two methods lead to identical results in the important parameters then I choose the most inexpensive and easiest method. That was my point

Wouter

You are so easy to wind up.

If you want to use cheaper line and tie knots, then go a head. If I have D12, I will splice.... It does not take long.

If a splice weakens the line by 20% and a knot weakens line by 40%, then you can use lighter line with the spliced line to achieve simular results. Knowing you race a boat that is significantly over class weight and you are not concerned with being competitive, I am sure weight does not bother you anyway. <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />