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Re: North white center "strong-line" what is it?

Posted: Mon Oct 01, 2012 6:38 pm
by Johnny Rotten
clydesdale wrote:it's woven from ken winners white short hairs which is why the new bar is so expensive.

http://www.samsonrope.com/index.cfm?rope=192

7/64th's works
LMAO! thanks clydesdale given others input I pretty much deduced that what it had to be, (not the white hairs part though) :lol: given the 5th has no load and upon inspection it is a 12 strand rope between 2-2.5mm


JGTR: Thanks I agree totally 5th line carries <50lbs, (unltil you flag it) I pull on it all the time. wasn't thinking it through.


Was just worried it might be a length of unobtainium with ultra high break strength. but PBO and Vectran aren't suitable for UV exposure so it pretty much has to be dyneema, SK 90 doesn't have much better strength (in those small sizes) to be significant nor is it commercially available in <3mm sizes so I put in an order for some of the 2.5mm.

Billie: with a 1600lb break strength, a reasonably prudent engineer would think twice before tieing a knot in this line Rule of thumb is ~30% decrease in strength with a figure 8. The smaller the rope diameter the worse the effect will be relatively speaking this is SMALL rope (10mm rope for example sees a 15% decrease) All this stuff has been spec'd with a factor of safety and likely accounts for some wear and degradation and is backed up by abusive testing and warranty/field reports, so you Might be OK..Just understand you've significantly weakened what is likely the highest stressed component on the bar and it hasn't broken.....yet.
Definitely negating any benefit from the extra strong front lines north puts on.
If you can do eye splices (easy and a good skill to learn if you can't) this stuff is really cheap to buy if you want to shorten your line with more confidence.

Re: North white center "strong-line" what is it?

Posted: Mon Oct 01, 2012 7:10 pm
by Billy B.
Johnny Rotten wrote:


Billie: with a 1600lb break strength, a reasonably prudent engineer would think twice before tieing a knot in this line Rule of thumb is ~30% decrease in strength with a figure 8. The smaller the rope diameter the worse the effect will be relatively speaking this is SMALL rope (10mm rope for example sees a 15% decrease) All this stuff has been spec'd with a factor of safety and likely accounts for some wear and degradation and is backed up by abusive testing and warranty/field reports, so you Might be OK..Just understand you've significantly weakened what is likely the highest stressed component on the bar and it hasn't broken.....yet.
Definitely negating any benefit from the extra strong front lines north puts on.
If you can do eye splices (easy and a good skill to learn if you can't) this stuff is really cheap to buy if you want to shorten your line with more confidence.
I have over a year on my (double) figure eight knot, As a life long mountaineer, and sailor, (so I can work the f*** out of a fid.`.). I had no problem placing the knot in the line, knowing the reduction in strength, there is still plenty of strength left. It is on a kite bar for use on water that has a saftey line that backs it up, I have no fear of it failing, and if it did the saftey line should be still usable so no big deal in my opinion.. I wouldn't glide on it but if most prudent engineers analize almost anything I do they would be nervous for me....To each his own, I am not going to the moon, just kiteboarding... :thumb:

Re: North white center "strong-line" what is it?

Posted: Mon Oct 01, 2012 10:14 pm
by SupaEZ
I agree with Billy B. that his double eight knot is Supa safe and OK

The #1 reason is the "location" of the knot....at the "end' of the white line...furthest point from the kite

In effect the thick white line under load stretches and absorbs energy before reaching the knot

......................... :surf: :sun: .....................................................................