Contact   Imprint   Advertising   Guidelines

Changing Mixer Line Length

For all foil kite riders
User avatar
PugetSoundKiter
Medium Poster
Posts: 139
Joined: Sat Feb 20, 2016 5:53 pm
Kiting since: 2009
Style: Wake TT, Strapless Surfboard, Landboard
Gear: Cabrinha, Ocean Rodeo, Slingshot, Naish, North, Pansh, Ozone, HQ, Peter Lynn
Brand Affiliation: None
Has thanked: 17 times
Been thanked: 5 times

Changing Mixer Line Length

Postby PugetSoundKiter » Sun Jun 30, 2019 5:36 am

Sketched out what I think happens if A, B, C or Z line lengths are changed (one at a time) :think:

After tuning some kites, I wanted a reference graphic so I could easily pick which line might be the best to lengthen or shorten. I only drew one modification per line but, for example if I were to lengthen, instead of shorten a line (or vice-versa), then the results would be reversed.

If you find an error, let me know. Hopefully it's helpful to others.
A-Line.JPG
B-Line.JPG
C-Line.JPG
Z-Line.JPG

foilholio
Very Frequent Poster
Posts: 2964
Joined: Sun Aug 23, 2015 3:20 am
Kiting since: 1337
Local Beach: Ventura Beach
Favorite Beaches: Tarifa
Style: Airstyle
Gear: Foils
Brand Affiliation: None
Has thanked: 144 times
Been thanked: 69 times

Re: Changing Mixer Line Length

Postby foilholio » Sun Jun 30, 2019 6:26 pm

Your first diagram is wrong because of not accounting for the change on B pulley line through C pulley line. B should be -3/4. Maybe do them all in whole numbers and not fractions too.

Other problems are I guess you are trying to represent what happens to B and C when A and Z remain level, if you just change B or C both A and Z still remain level so... to express a change then on B or C you too would have to express it on A or Z. So diagrams 2 and 3 are not valid as is.

Another option to adjust and diagram is the lengths of the pulley lines.

Diagram 3 and 4 has no effect on depower, only altering the limit of B in relation to A effects depower. So changing A or B length or altering the pulley line lengths.

Other errors, any lengthening of Z or A or shortening of B will increase stability not may. C though is a little complicated so may is a suitable term. Any shortening of B or C will increase reflex.

Also depending on the position of ABCZ they have differing effects. Kites often transition these positions at the tips. So if you adjust bridles there you need to treat them with their position not their label. As in if C is where B is it is more B.

User avatar
edt
Very Frequent Poster
Posts: 5583
Joined: Fri Jul 16, 2010 6:27 am
Kiting since: 2010
Local Beach: Michigan
Gear: slingshot liquid force wainman pansh naish duotone cwb burton ronix rpm ozone
Has thanked: 46 times
Been thanked: 81 times

Re: Changing Mixer Line Length

Postby edt » Sun Jun 30, 2019 8:21 pm

PugetSoundKiter wrote:
Sun Jun 30, 2019 5:36 am
Sketched out what I think happens if A, B, C or Z line lengths are changed (one at a time) :think:
awesome puget. Anyway to change the mixer to make the kite turn faster/slower? (also chime in please foilholio if you know)
These users thanked the author edt for the post:
PugetSoundKiter (Tue Jul 02, 2019 5:05 am)
Rating: 10%

foilholio
Very Frequent Poster
Posts: 2964
Joined: Sun Aug 23, 2015 3:20 am
Kiting since: 1337
Local Beach: Ventura Beach
Favorite Beaches: Tarifa
Style: Airstyle
Gear: Foils
Brand Affiliation: None
Has thanked: 144 times
Been thanked: 69 times

Re: Changing Mixer Line Length

Postby foilholio » Mon Jul 01, 2019 11:36 pm

Higher camber will turn faster. If you really want the kite to fly faster through the turn you should alter the tip to be higher camber. You will degrade the overall performance of a kite doing either though. there are many other ways to make a kite turn faster, like longer bar, pulley bar, maybe different mixer and the simplest just pulling on the rear leader lines.
These users thanked the author foilholio for the post (total 2):
PugetSoundKiter (Tue Jul 02, 2019 5:05 am) • edt (Tue Jul 02, 2019 8:14 pm)
Rating: 20%

User avatar
PugetSoundKiter
Medium Poster
Posts: 139
Joined: Sat Feb 20, 2016 5:53 pm
Kiting since: 2009
Style: Wake TT, Strapless Surfboard, Landboard
Gear: Cabrinha, Ocean Rodeo, Slingshot, Naish, North, Pansh, Ozone, HQ, Peter Lynn
Brand Affiliation: None
Has thanked: 17 times
Been thanked: 5 times

Re: Changing Mixer Line Length

Postby PugetSoundKiter » Tue Jul 02, 2019 5:28 am

Thanks foilholio, when I get some free time I’ll update these diagrams. Hi edt, my goal was to graphically see what changing A,B,C or Z may have on Camber, Lift, Stability, etc. I agree with foilholio there are other ways to try and quicken turning. Flying flysurfers I have not had to tweek much, they are a great quality design. Flying a Chrono and R1 they need a little more attention to the speed system when they fall out of tune. I discovered using a very long throw/trim bar that the Ozone pulley lines knots for adjustment can jam in one of the speed system pulleys. But the Ozone kites are high quality. The A15 Pansh kites I got flew fine and when I did some bridle/mixer adjustments the trade-off did not outweigh the benefits. It was when I got the Aurora2 8m & 10m kites that I thought they should have good potential but take some tuning to sort out.

I thought both the 8m and 10m stock were very lifty and strong pulling for their sizes. But they also would overfly in gust when flown high. After static flying each, to bed the bridle lines, I measured the mixers for each: 8m (A=Z, B=2.25”, C=1.5”, each side) and 10m (A=Z, B=2.5” (right side) B=2.75 (left side), C=2”, each side). So, I tried to reduce the camber to gain stability, sacrificing lift. An easy way to do this was to lengthen the A-Line. Access to the A-line is easy for tuning, you only need to remove the center line pigtail from the kite. This worked fine on the 8m viewtopic.php?p=1040778#p1040778, I was lucky enough that the ratios worked out and by only lengthening the A-Line, I got the kite to fly good static and it rode well using a landboard.

The 10m seemed to fly well static in stock tune, so I tried using it with a surfboard but found out it is unstable when I would sine it and it would pick up speed so I could load it up, it would quickly stall the kite. So I used the same trick to lengthen both the A-Lines from 46” to 49.5”, this gave me A=Z, B=.75, C=.5 (right) and A=Z, B=.25, C=.5 (left). So unlike the 8m kite, the 10m kite left and right did not match (Bs are more different, remeasured but not sure why only Bs are more different and not As or Cs, result is a more asymmetric wing, assuming bridles are symmetric, maybe I'll check again with a long mixer test). Flying it static it was more stable, but backstalls a little with the bar in. I remember what foilholio said about the 8m tuning.
viewtopic.php?p=1049232#p1049232
For example with (B) Mod1, Mixer A=Z, B=+0.75”, C=+0.5”. If you remove your A extensions and instead, lengthen Z +6" and C +2", you would then have the same mixer test ,(B) Mod1, Mixer A=Z, B=+0.75”, C=+0.5”, but not change the maximum depower or depower limit by way of not altering B. You could achieve the same depower limit, with the bar or trimmer pulling in for 4x what you originally shortened A. For your Mod1 you lengthened A 2.5" that would mean you lost 10" of depower throw, a massive amount!”
For landboarding with the 8m, the direct feel to the kite is positive and flying in low winds the short depower throw works good. But for kitesurfing with the 10m having a smooth longer depower throw is better. I’ll try using the 10m with the longer A lines with the surfboard just to understand if it got more stable and if the depower is too abrupt. And remove/add knots to the amsteel A-lines to see the effects. I was hoping to avoid this, but I suspect I may end up having to rig a more complicated adjustable bridle to move Bs, Cs, and Zs independently. So, I made the diagrams above, hoping to save myself rigging trial & error time, and to verify in theory what should happen with what really happens.

foilholio
Very Frequent Poster
Posts: 2964
Joined: Sun Aug 23, 2015 3:20 am
Kiting since: 1337
Local Beach: Ventura Beach
Favorite Beaches: Tarifa
Style: Airstyle
Gear: Foils
Brand Affiliation: None
Has thanked: 144 times
Been thanked: 69 times

Re: Changing Mixer Line Length

Postby foilholio » Tue Jul 02, 2019 7:25 pm

PugetSoundKiter wrote: The A15 Pansh kites I got flew fine and when I did some bridle/mixer adjustments the trade-off did not outweigh the benefits.
What adjustments did you try?
PugetSoundKiter wrote:10m (A=Z, B=2.5” (right side) B=2.75 (left side)
Check the symmetry higher up as Pansh can make compensations with some bridles for errors in others. It would be good to have it matching at most importantly the canopy but also the mixer.
PugetSoundKiter wrote: I tried to reduce the camber to gain stability, sacrificing lift. An easy way to do this was to lengthen the A-Line.
The easiest way to do this is lengthen Z. Z should be your general go to in tuning kites. If you alter A or B you change the depower limit. You may want to do that but you can also do that with the bar. When your depower is reduced the kite loses range, both top end obviously but lowend too as it flys slower and stalls easier.

When you alter A you also alter the ratio of B to C, B being reduced more than C. If you wanted to achieve that when altering Z instead you would also need to alter C, lengthening it.

Something more on depower limit, is all mixers and bridles shrink to reduce it. To get a kite flying like new you want to increase not decrease it. When a kite won't fly forward in light wind but will fly at the window edge this is because of the depower limit. You could actually mod a kite to increase it and so improve the lightwind by reducing stall when it's deep like relaunching.

Some older likes will collapse and invert easy with too much depower. Most new kites are designed to fly with B slack at the window edge, so solely off A. You can easily observe the tension in bridles or lines by how they bend. More bending= no or less tension, i.e. slack.
PugetSoundKiter wrote: the kite to fly good static and it rode well using a landboard.
In the end that is all that is important, if you like how it flies. The customization of kites should be purely to how you like them.
PugetSoundKiter wrote: so I tried using it with a surfboard but found out it is unstable when I would sine it and it would pick up speed so I could load it up, it would quickly stall the kite.
I am not sure about this. Can you describe it a bit more?
PugetSoundKiter wrote: lengthen both the A-Lines from 46” to 49.5”, this gave me A=Z, B=.75, C=.5 (right) and A=Z, B=.25, C=.5 (left)
You need to check and sort out any asymmetry, from the lines to the canopy.

Lengthening A 3.5" alters B -2.625" C -1.5" and you lose 14" of depower. Which is a lot in all aspects .
PugetSoundKiter wrote: Bs are more different, remeasured but not sure why only Bs are more different
Something there is a different length. Most likely B mains or pulley lines, but it could be more. You can tie a knot in the sewn end to make an adjustment on the long part or add a pigtail to the shorter one. You need to check at the canopy though as they may like I said earlier be compensating somewhere else.
PugetSoundKiter wrote:remember what foilholio said
Well it appears we have been here before lol.
PugetSoundKiter wrote: but I suspect I may end up having to rig a more complicated adjustable bridle to move Bs, Cs, and Zs independently
You should probably only need to adjust Z. Just make pigtails out of a loop of kite line with a figure 8 knot on the end. Easy.

If you do need to adjust B and C you can add pigtails or just cut the pulley end stitching open and use a bowline knot to adjust.
These users thanked the author foilholio for the post:
PugetSoundKiter (Mon Jul 08, 2019 6:20 pm)
Rating: 10%

User avatar
edt
Very Frequent Poster
Posts: 5583
Joined: Fri Jul 16, 2010 6:27 am
Kiting since: 2010
Local Beach: Michigan
Gear: slingshot liquid force wainman pansh naish duotone cwb burton ronix rpm ozone
Has thanked: 46 times
Been thanked: 81 times

Re: Changing Mixer Line Length

Postby edt » Tue Jul 02, 2019 8:14 pm

foilholio wrote:
Mon Jul 01, 2019 11:36 pm
Higher camber will turn faster. If you really want the kite to fly faster through the turn you should alter the tip to be higher camber. You will degrade the overall performance of a kite doing either though. there are many other ways to make a kite turn faster, like longer bar, pulley bar, maybe different mixer and the simplest just pulling on the rear leader lines.
interesting, so just the tip of the canopy gets a higher camber. I'm already using a 2:1 pulley bar and the kite is still too slow.

foilholio
Very Frequent Poster
Posts: 2964
Joined: Sun Aug 23, 2015 3:20 am
Kiting since: 1337
Local Beach: Ventura Beach
Favorite Beaches: Tarifa
Style: Airstyle
Gear: Foils
Brand Affiliation: None
Has thanked: 144 times
Been thanked: 69 times

Re: Changing Mixer Line Length

Postby foilholio » Fri Jul 05, 2019 4:04 pm

Yep just put some loops in Z at the canopy around each LCL.

User avatar
PugetSoundKiter
Medium Poster
Posts: 139
Joined: Sat Feb 20, 2016 5:53 pm
Kiting since: 2009
Style: Wake TT, Strapless Surfboard, Landboard
Gear: Cabrinha, Ocean Rodeo, Slingshot, Naish, North, Pansh, Ozone, HQ, Peter Lynn
Brand Affiliation: None
Has thanked: 17 times
Been thanked: 5 times

Re: Changing Mixer Line Length

Postby PugetSoundKiter » Mon Jul 08, 2019 6:19 pm

foilholio wrote:
Tue Jul 02, 2019 7:25 pm
PugetSoundKiter wrote: The A15 Pansh kites I got flew fine and when I did some bridle/mixer adjustments the trade-off did not outweigh the benefits.
What adjustments did you try?
I have used the A15 18m unmodified on a 55cm 2:1 pulley bar and 30m lines. It is good 12-20mph on a twin tip but more fun on my 5’4” Naish Skater powered 12-20mph. Definitely learn the limits of board fins with this combo around 20mph, even with my 6’2”, 200# of leverage. Used a quad fin board too, but powered on a tri fin is more fun. On the A15 12m I changed the Z-Line length but ended up returning to the stock setting as a good compromise. Not much else to share, but I do like the A15 for easy LEI type riding and I had followed your extensive modifications documented here. Instead of trying to improve the lower AR A15, I was going to try and take the higher AR Aurora2 and make it more stable. Hoping to have a better upwind angle kite than the A15, in a smaller size, and easy riding for hydrofoil use.
foilholio wrote:
Tue Jul 02, 2019 7:25 pm
PugetSoundKiter wrote: so I tried using it with a surfboard but found out it is unstable when I would sine it and it would pick up speed so I could load it up, it would quickly stall the kite.
I am not sure about this. Can you describe it a bit more?
What I was trying to convey with the stock 10m A2 stalling when loaded up is not that this is unique or a trait of this kite. I would expect to be able to sheet in and stall a kite this size in lower winds, but with the high camber setting when I would sheet out with my long throw bar, the kite would recover from the back stall and shoot too far forward, I suspect due to the high camber/lift. With the kite low it could fall back and recover but flying at a high angle it would overfly and game over.
foilholio wrote:
Tue Jul 02, 2019 7:25 pm
You should probably only need to adjust Z. Just make pigtails out of a loop of kite line with a figure 8 knot on the end. Easy. If you do need to adjust B and C you can add pigtails or just cut the pulley end stitching open and use a bowline knot to adjust.
I’m going to follow your suggestion and go back the original A length and lengthen Z instead and then then make an adjustment to C as needed. I’ll check the symmetry of the bridles and pulley lines. My goal was not to limit depower, just to make it more stable by eliminating overflying. I’ll take note that Bs should appear somewhat slack at the window’s edge. I think I’ll also shorten bar lines from 22m to improve the feel and better observe what is going on at the B, C, and Z connections.
foilholio wrote:
Tue Jul 02, 2019 7:25 pm
Another option to adjust and diagram is the lengths of the pulley lines.
And you got me curious about the pulley line shrinking scenarios.
So I’ve updated the diagrams:
- Changing Z line
- Changing A line
- Shrinking B pulley line
- Shrinking C pulley line
1-Zline.JPG
2-Aline.JPG
3-Bpulley.JPG
4-Cpulley.JPG

kitexpert
Very Frequent Poster
Posts: 809
Joined: Sun Aug 09, 2015 11:20 pm
Kiting since: 2003
Gear: many kites, also diy
Brand Affiliation: None
Has thanked: 7 times
Been thanked: 15 times

Re: Changing Mixer Line Length

Postby kitexpert » Wed Jul 10, 2019 4:51 pm

I advice to keep separate two functions of a mixer: 1) to change AoA of a kite to make it depowerable 2) to adjust line rows in order to change camber or more importantly to return settings back to original.

Actually only 1) is a true mixer property. 2) could as well been done in the bridles, but it is more convenient to do it in the mixer. But in many cases it would be done better in the bridles because it gives more possibilities. Actually general camber adjustment in the mixer is quite rough way to do it.

So, mixer pulling ratios are fixed. B is usually pulled 1:4 of the bar movement and C 1:2. A is fixed and Z is pulled 1:1 (some rare exceptions do exist, but are not that relevant). However if bridle (mixer) is very bad out of tune some line rows may even slack and then engaging later thus affecting to pulling ratio.

How kite finally changes AoA (and usually to some extent camber) depends not only pulling ratios but also 3) line row locations at the chord which aren't of course adjustable.

I repeat: main reason for mixer tweaking is to correct changes which have happened because lines (pulley lines, bridle) have shrunk.

Original factory settings are carefully designed and adjusted for the best general behavior of the kite (stability, performance). Then all line rows are level, canopy is clean and well supported. Kite air foil shape is kept original while kite changes AoA when kiter sheets in/out (with the possible small effect of line row locations).

However there is some room for adjustments, but it will not happen without drawbacks. One kiter may think: "My kite feels a bit powerless and slow, so I tune it to a bit higher camber to get more performance", and another one: "My kite is too unstable, I adjust it to a lower camber so it won't collapse in gusts". In other words these two have different opinions how they want their kites to be.

In perfect world they should have their own versions of that kite: one having higher and other lower camber airfoil. Then need for mixer tweaking would be less and untweaked kites would perform slightly better.

To believe that mixer tweaking is some kind of secretive method to improve kites is wrong. Same is for the bridle modifications (assuming kite and bridle are of decent quality). In some cases it is possible to redesign completely and to achieve observable benefits, but kite will be same nevertheless.

Things that make kite good or less good - which really affect how it performs - are much more fundamental than where bridle/mixer adjusting can reach.

In short: don't make these things too complicated. Try to keep different parts and functions of a kite separate. Main rule is to try always restore factory settings.


Return to “Foil Kites”

Who is online

Users browsing this forum: Herman and 2 guests