Page 2 of 3

Re: North 4-line bar safety diagram?

Posted: Fri Aug 15, 2014 1:00 am
by Dan-at-Duotone
I'm sorry you're frustrated. It appears that you've found someone who has more information than I do. I'd recommend contacting them directly for the information you're looking for.

As far as a simple upgrade kit, I still think that you're looking at replacing several lines. Perhaps all you will need is the front lines for a 2015 bar. I really don't know. But before you get angry at me or North I'd recommend you wait and see what North offers.

As far as single vs double lined safety I feel I'm flogging a dead horse here... You can check for previous posts on pluses and minuses of each system. We felt that the way our kites worked in the past the double-front line release was more safe. Early Evos would go into a death spiral when released onto a single front line. For some reason it appears that the same issue does not happen to newer kites, as such we are moving to a single front-line release. We do our best every year to make the gear as good and as safe as we possibly can. We also do our best to keep our gear as backwards-compatible as reasonably possible without overly hindering design progression.

-Dan

Re: North 4-line bar safety diagram?

Posted: Mon Aug 25, 2014 12:01 am
by Vertical
I have actually updated the safety system to follow the safety of the 5 lines trust bar, using a spare metal ring and the red stopper ball. I haven't tested it yet, but it should work as well as the 5th line safety (well apart from being on the side, rather than in the center)
North Lines safety.png
5th line - 4 lines conversion

Re: North 4-line bar safety diagram?

Posted: Mon Aug 25, 2014 3:51 am
by Westozzy
So essentially you have converted a 5th line bar into a single front line flag quad bar right...

Question (as I need to do the same on my brothers bar), isn't the Y split higher up on the 5th element?

If not I presume you just got a normal quad bars saftey red line and attached it to a single front line with a stopper...

If the Y split is higher up (and I thought it was) how did your source the correct saftey red line?

Cheers in advance...

Re: North 4-line bar safety diagram?

Posted: Mon Aug 25, 2014 4:54 am
by Vertical
I have modified a Quad bar, taking a metal ring and a ball stopper from a 5 lines bar.

The bar is still 100% North trust quad, with the same lines lengths for the 4 lines. But With the changes it flags on a single line, in my case the red one.

I put the photos side by side to show how the safety system is in fact the same idea for 5 lines of for the updated 4 lines.

Re: North 4-line bar safety diagram?

Posted: Mon Aug 25, 2014 6:40 pm
by Peert
@ Vertical: I assume you have left the Y-split at exactly the same position as it was while being a 5 line bar? So quite high up? I used to have it like this at well.

last month I decided to bring the Y-split further down. I had the feeling my draf does not like high split.

The problem here is that you want to make sure you still have the required minimum +/- half LE tube length of single line flag travel (do not know how to frase this correctly). To do this you bring the ring down and need a knot that does not go through stopperball but does (easily) go through the heart of the safety/CL. Depending on Ball, hole in Ball and thickness of line used this is works fine.

Re: North 4-line bar safety diagram?

Posted: Tue Aug 26, 2014 2:26 am
by Vertical
Peert wrote:@ Vertical: I assume you have left the Y-split at exactly the same position as it was while being a 5 line bar? So quite high up? I used to have it like this at well.
I started from a North Quad Bar, not a 5 lines bar. I converted a Quad Bar from 2 front lines safety release into a single line.
I Have modified a quad bar with 22m lines to allow single line flag out and not a 5 lines bar to convert it to 4 lines.
The lines are identical in length as they come from factory in the quad bar (with the low Y). The Y is still at the same spot as it is still a quad bar.

The only things that come from the 5 lines bar are 1 metal ring and 1 red ball stopper.

The result of the conversion is a quad bar with the same Y in the same position but it flags out on a single line (as the lines haven't changed).

Re: North 4-line bar safety diagram?

Posted: Tue Aug 26, 2014 8:47 am
by Onda
@ Vertical:
Your setup might function.
But I´m afraid the red stopper ball will not be strong enough to carry all the load of one front line vs. the metal ring.
Be reminded that this cheap plastic ball - in the 5th Element setup - only has to carry the load of the "loaded 5th line", which is very significantly lower than the full frontline load.

If the ball would crack under load, the relatively small knot (covered by the ball) would slide through the metal ring, wouldn´t it?
In that case you wouldn´t be able to return to the beach (continously flagged out kite). And if it would happen during a high jump you would fall out of the sky like a piece of lead.

It would be better to use a smaller diameter ring and a "proper" (= lasting and not line killing) thick knot instead of a small knot plus ball.
BUT: This knot mustn´t slide through the bar hole with any resistance, or alternatively with total resistance. The bar could get stuck at / behind this knot after releasing the kite, which might make it impossible to pull the bar back to you after a safety release.

Regards, Onda

Re: North 4-line bar safety diagram?

Posted: Tue Aug 26, 2014 10:17 am
by Westozzy
Could have a point here, although I'm sure the ozone front line is supported with a ball like this...correct me if I'm wrong been a while since I've worked on one. :D

Re: North 4-line bar safety diagram?

Posted: Tue Aug 26, 2014 11:03 am
by jedi1
Onda wrote: If the ball would crack under load, the relatively small knot (covered by the ball) would slide through the metal ring, wouldn´t it?
In that case you wouldn´t be able to return to the beach (continously flagged out kite).
If the ball cracks, it won't flag your kite. The kite will only flag if you have tension on only one line, without the ball you will still have tension on all 4 lines (unless you have an ultra long dangling safety line). It is there so you have one attachment point to both front lines, so you can use your depower strap. If there was no stopper ball, pulling the depower strap would only shorten one line. So worst case scenario, you will have one of your lines longer than the other, which will make the kite turn one way. Anyways Ozone uses a ball like that, so does Best and you can buy one from their dealer if that is a concern.

The only problem with this modification is that a North front line is sleeved, which makes it bulky. For this system to work the front line has to pass through the hole in the Iron Heart, where the safety line goes through. If it doesn't, then it might not work as mentioned earlier. You can either splice a line on this end (but it requires some skill and I wouldn't recommend it, if you don't know what you are doing) or attach the safety line the way Naish does it
Image

Re: North 4-line bar safety diagram?

Posted: Tue Aug 26, 2014 12:32 pm
by Vertical
Onda wrote:@ Vertical:
Your setup might function.
But I´m afraid the red stopper ball will not be strong enough to carry all the load of one front line vs. the metal ring.
Be reminded that this cheap plastic ball - in the 5th Element setup - only has to carry the load of the "loaded 5th line", which is very significantly lower than the full frontline load.

If the ball would crack under load, the relatively small knot (covered by the ball) would slide through the metal ring, wouldn´t it?
In that case you wouldn´t be able to return to the beach (continously flagged out kite). And if it would happen during a high jump you would fall out of the sky like a piece of lead.

It would be better to use a smaller diameter ring and a "proper" (= lasting and not line killing) thick knot instead of a small knot plus ball.
BUT: This knot mustn´t slide through the bar hole with any resistance, or alternatively with total resistance. The bar could get stuck at / behind this knot after releasing the kite, which might make it impossible to pull the bar back to you after a safety release.

Regards, Onda
My only concerns are the ring not being able to hold the load of the front line. The ball is the same type used in the Ozone bars and they seem to hold for them, as westozzy said before.
If the ball breaks, the tension would be on the safety line, and it may be a little unstable to fly, but It would still work. If the ring breaks, is when things may get a bit uglier to get back to the beach. The Ozone part looks a lot stronger than the little metal ring (maybe using 2 rings together?). I wonder what the system for the new 2015 North quad bar looks like.

After all this back and forth, as I said in the other thread, I might consider converting the quad bar into a 5 lines using the same safety setup used in the 5 lines bar. I'd be getting an extra line for the center leaving it without tension, so it doesn't affect the arc of the Dice and still maintain the low Y from the Quad bar. 4 lines with 2 front lines safety is still very dangerous. My mate had to release his Dice on 35+ knots on the beach and he almost ended up in the bushes because of the power that he still had on his 6m kite using the 2 front lines safety. I had a similar situation once. Not very good feeling.