I dare say you will find your front lines are not even and your rears almost certainly won't be. If you start adjusting the canopy and the lines or bridles are out it can be a bit difficult to get the kite close to flying neutral.foilholio wrote:To adjust lines you first need to take any shrink out of them. Applying a large even force to each line seems to work well. You can connect both lines in a chain so you can use your full body weight and the force is even.
A small rope run through a pulley with 2 lines connected to each end of the rope, the other ends to something solid and even, will allow you to apply even tension at different lengths. Sharpie marks made at the same point/s on each line close to the pulley end, can be used as a guide to adjust the lines later inside.
I'll add to make sure you double or triple stitch the relief section. Also you could alter the side the kite turns to but you would need to make the pleats on the bottom of the kites skin on that side. Why you would or wouldn't want to do it on which side depends on which side of the kite you are trying to make the other replicate. To understand this I will explain what is happening. By tensioning the top skin cord wise you are reducing camber on the airfoil and increasing the AOA. This will make the wing section more stable and more draggy=slower. By tensioning the bottom you do the opposite, more camber, less AOA, less stable , less drag=faster. So if you look at your two wing sides and one is obviously faster than the other and less stable. Do you want the less stable tip to be more stable or the more stable tip to be less. Notice if you choose more stable you will have slightly less depower and slower turning ! One of my kites I should have changed the bottom skin on the opposite side, but so far I have only sew top skins but I have played with tape on the bottom though.foilholio wrote: Great article written by Peter Lynn explains it http://www.peterlynnhimself.com/Pilot_Tuning.php. The bit to focus on is the sewing at the end. The diagrams dont match the explanation. Assuming the front lines and A bridles match, and the A tow points match, proceed to sew.
How I did it. Starting at the opposite side/end cell the kite turns to. At each cell line on the top skin fold the kite in half. I used one hand to hold the leading and trailing edge at their extremes. I then placed a finger in the middle to find the center of the cell wall. Use a pen that will soak through the cell and place a dot on the top skin near cell wall. Do this for a few cells in succession, the more the worse the turning problem. Hunt down the dots inside the kite through the the cell holes. Starting at the end cell. Sew a one ripstop square width pleat in the top skin,from cell wall to cell wall. Leave a 2 cm relief on each end, i.e. sew a diagonal on each end of the pleat so the pleat doesn't start straight at the cell walls but gradually. Use the ripstop squares as a guide to sew an even straight line. Do this to a few cells and subtract or add more later or one at a time. If the kite is unflyable you'll need about 6.
There is other possibilities of doing bigger pleats, pleats at other places than 50% and multiple pleats per cell. I would guess changes to the end cell/s have the biggest effect. This will also make the kite more stable. If applied to both sides it would reduce or stop tip flap, depending on the amount done.
jakemoore wrote: Consider a kite with bias to one side, bridles and lines check out with beautiful symmetry. Less than 10 hours flight bought it brand new. Powered flight is good. Depower it turns right. I've tried empirically shortening lines with knots or lengthening with lcl. No satisfaction.
jakemoore wrote:I'm convinced it's the canopy. I've inspected it carefully on the ground and in flight eg looking for a busted cell wall. No satisfaction.
Yep tape will work to test. I do it in the middle. In reality you can do it anywhere but the middle works. You could do 1 pleat in the middle or 2 with 1 at each third. The middle is simple. Where the sewing and exactly how it went wrong in manufacture is any ones guess, maybe an expert could see:-?. I like to apply the solution(pleats) broadly though so I don't distort things too much. Obviously where the seams are longer there is more chance for more error, but also the closer you get to the tip the more effect an error has as the kite can be levered with less effort from there....jakemoore wrote:I'll do the pleat first with tape. How far front to back? Please walk me through it.
Users browsing this forum: No registered users and 4 guests