Hi. Following passionately the genesis Castle mod topic I decided to register this forum to bring my experience here. So yes i am Simone from italy and i am new. Back to the topic:
Since i noticed that slack on the C and Z lines of my genesis 6m, i started to think Very much how to solve it,
So reading and reading and researching i got into a kite forum where was a simple solution given.
U can change the castle balance using B line as pivot line and adjusting the length of C or A. IMO the simplest was to shorten A and so i did. Turning the A lines into and around a ring i found out that with 2 turns the A line shortened increased the thension on the back lines, especially C and Z.
3 turns made the A too short and the AoA negative, so the kite frontstalled continuously. But with 2 turns it works quite well. No camber change, just rebalanced the castle.
Now the responsiveness as well the turning speed are increased. Another guy has read about it on YouTube comments and did the same mod with satisfaction. What do u think about it?
I have a little trouble with some of your language. Maybe you are using google translate? Castle=Mixer?
If Z and C are too slack usually you would either pull the bar in or adjust the line trim. Otherwise you would make Z and C shorter.
I tend to avoid adjusting A or B because they alter the minimum AoA or depower limit as you found out. That is unless you desire to change that, in which case I would adjust B and with it also C and Z to maintain their ratios. You can also adjust the pulley line instead.
You can not make a single change to either A or B or C or Z without changing camber. Only by changing multiple of them in ratio would you maintain the camber.
" If Rear pulley moves down 4, rear gets pulled 8, but C moves down half of that for 4, the resulting pull on the rear is then 4."
The C pulley moves 2/3 of the movement of the control line. Note that the line thru the rear pulley is connected to the C line. The question is how strong the Z tension is.
Well I was not 100% sure how it would work. There is the strong possibility Z and C get pulled in unison, giving you more movement of C but then maybe the ratio is not 421.
No , on a standard foil kite, camber is not a matter of tension.
It certainly is, foil kites are flexible. You can observe the deformations, though downward deformations of reduced camber are hard by yourself.
Regis-de-giens wrote:It is a matter of geometry assuming rigid chords
Assuming a foil kite is rigid is a mistake. They have some rigidity but remain flexible.
profile and camber variation is "imposed" geometrically, and MUST be independant on tension in the briddles. Any variation in tension (due to gust, turbulence, turns against the canopy) should bot affect the profile . Other wise kite stability / control will suffer. Geometry shall on the contrary remain stable in all range of tensions in briddles.
Ok I get what you are thinking. The problem with a pure geometric model is the kites shape changes with tension and how it is applied. You do have the sewn shape but depending how the bridles are things change. The tension model is the reality of the kite though. You vary tension then also geometry can change. More tension on B can slacken C. If pulling one bridle then the others change. Foil kites because they have not much rigidity are difficult to design for. Unlike LEI ,which I think what kitexpert is really an expert in, you can not just force things more.
If you look Speed4dlx wingtips you see a fold there when you sheet in, one line row can't unfortunately support it well enough. This problem becomes even more evident when kite is used and inner pressure gets worse. Almost all Speed4dlx''s suffer wingtip problems, also mine.
Oh dear big deal the wing tips fold. I mean Z should really have less tension there to improve the L/D.
If some kite really has camber decrease then increase during powering up it is because Z is too loose or it is of insignificant scale.
kitexpert wrote:In any case it is not a useful property for kite.
Wrong again. It is very useful. Maybe stick to designing LEIs.
kitexpert wrote:Calling any deformation of kite "camber" is too unclear
What are changes to the shape then? As described on the airfoil. Curves or folds down in say the front third, middle, rear third and then rear? What are those changes called again? On a airfoil or wing? The word starts with a C I think. Maybe you can help me, I have forgotten.
No wonder you struggle with these things. You can't even a hold a rigid use of the words.
Then when kite is powered/depowered this build in camber may or may not change, depending how it is designed to work (bridle locations, mixer pulley ratios).
Great to explain this for the 100th time, we are talking not usually about designing kites but kites already designed. I personally have not seen depowerable kites that do not change camber.
Changing camber by tweaking the mixer - having some camber preset - can never be more than fine tuning.
It can do far more than just "fine tuning"
kitexpert wrote:Real changes in camber require different kite shape
The amount that camber gets ramped into a kite from a mixer would never work as a sewn shape. The kite would just collapse.
if this is tried to be achieved by tweaking kite will distort itself
So? and it is tried and done and it does distort the kite and the kite is better for it. How many years now and you can't still grasp variable camber? Stick to LEIs.
Some parts of it lack fabric and some parts have too much, result is not at all smooth wing
So? You don't seem to mind that big lump on LEIs. I would say you would have been desiring it to be bigger out of some strange belief it was an airfoil. What is a small fold in the fabric in comparison. Probably many things I am sure when your foundational understanding of aerodynamics is wrong.