I've made quite a few, as you can probably tell from some of those e-book covers displayed on this site.
Dowel Diamond with sail back-lit by the sun
Dowel Diamond with sail back-lit by the sun
Although some knowledge about basic aerodynamics is handy, nothing beats bitter experience! I hope these tips ensure that there is a minimum of bitterness in your experience.
These general points only relate to flat single-line kites, including those with bowed spars or dihedral. So much depends on symmetry.
Symmetry is how closely the left and right sides of the kite are exact mirror-images of each other in various ways.
Get a coffee, this page is a little long. But interesting I hope!
On this site, there's more kite-making info than you can poke a stick at :-) Want to know the most convenient way of using it all?
The Big MBK E-book Bundle is a collection of downloads - printable PDF files which provide step-by-step instructions for many kites large and small...
Every kite in every MBK series.
Symmetry In Sail Shape
This is important. In other words, sail shape on one side is an exact
mirror-image of the shape on the other side. This also guarantees that
the sail area is precisely the same on both sides. In practice,
we can't be perfect, but there are ways to do a very good job with a
For example, by folding the sail material down the center-line
before measuring and cutting, a kite can be made very symmetrical in
shape. This gets a homemade kite off to a great start, although other
things can still go wrong.
The stronger the wind, the more sail area imbalance will show up, making the kite go left or right or even loop continuously.
Sometimes, with kites put together with tape, the sail can go out
of balance while the kite is flying. The sail might have slipped along a
spar or become partly detached, causing one side to have more area than
the other. Easily fixed!
Symmetry In Sail Billow
I discovered this one day when trying to figure out why a small
simple diamond wouldn't stay in the air, despite having a long tail. It
was accurately made, and reasonably light. Finally, I had a good look at
the sail while I swished it around indoors. Not on a line! I just held
the tail end of the kite in my hand and moved it around to get some air
pressure in the sail. I noticed that one side was fairly taut, but the
other bagged out a lot more. No wonder it wouldn't fly!
If you make a fairly big kite, this is unlikely to happen.
However, with a very small homemade kite, all sorts of inaccuracies can
creep in. Anyway, I re-attached one corner of the sail to tighten
everything up, and the kite flew fine after that!
Symmetry In Flexibility
2-Skewer Barn Door
2-Skewer Barn Door
A subtle one, this! Everything looks right, balances right, but when
the wind picks up... Around and around goes your homemade kite, all the
way to the ground. The cause is that one side of the kite is bending
more than the other! The effective sail area of the 'bendy' side is
slightly reduced, which means your beautifully symmetrical sail ain't so
symmetrical any more!
Depending on the design of kite, there might be other aerodynamic
effects too, as the flying surfaces distort. Whatever they are, the
effect is the same. Looping, or at least an annoying tendency to dive
to the same side all the time.
Synthetic materials like fiberglass or carbon fiber aren't likely
to give problems in a homemade kite, but natural materials are. The
solution is to do a quick check of flexibility when selecting material
for the horizontal spars. Lay a couple of sticks on a table, with most
of the length hanging over the edge. Does one stick droop noticeably
more than the other? Select a couple of sticks that match better, and
the resulting kite should have a respectable wind range.
Kites with multi-point bridles like the Barn Door Kite have an
advantage, since cross spars are attached at more than one point. There
is less tendency to bend. In fact, that's my original 2-Skewer Barn Door
in the photo up there.
Symmetry In Weight
If the sail on a homemade kite is good, then fitting spars to it should result in good balance. However, spar material is never exactly
the same from end to end. The synthetic stuff comes pretty close
though! So, when using natural materials, it's a good idea to make some attempt to get a match between the left and right ends of the horizontal spars. Just looking
at 2 spars can often give a clue. If one one is noticeably thicker or
darker than the other for example, chances are they don't weigh the
Also, when the kite is completely made, there might still be a small
imbalance for some reason unrelated to the spars. For example, the spar
caps or sail edging. For my MBK kites, that boils down to the exact
amount of tape I use!
From my experience, this might be the least important aspect of symmetry. It seems to have the most effect at the bottom
end of the kite's wind range. Also, I've found that high-flying designs
like the Delta are more sensitive to being correctly balanced in this
way, than other less efficient kites. Anyhow, balancing the kite is easy
to do with a few small bits of tape. It's a nice feeling, knowing that
your homemade kite is in nearly perfect balance!
Your Homemade Kite:
The Lighter The Better!
Hardly surprising, but did you know that this can have a big effect on stability as well as performance?
If there is too much weight near the edges of
the sail and / or the spar tips, the kite will want to keep going
around, if it starts to rotate for some reason. Rough air for example,
or a little gust from the side might tip it one way or the other. The
natural stability of the kite might not be quite enough to overcome this
inertia at times, causing it to loop around or dive into the ground.
Light weight will also help the kite go as high as possible.
Sounds logical! This is because the lifting force of the kite has to
lift 2 things against gravity - the flying line and the kite itself.
Saving weight on the kite means that you can let out more flying line
before you reach the maximum weight that the kite can lift.
So save weight where you can! Pick sail material that is strong
enough but light as possible. Use a minimum of tape or glue or whatever
other means you are using to secure the materials together. Use spars
that are only just stiff enough for the job. You will see all these principles employed in the designs in that e-book bundle.
Fly Higher With A Light Line
Use the lightest flying line possible, while making sure it is still
strong enough to avoid losing the kite. A rough rule of thumb is to
multiply the sail area in square feet by 3, which gives the required
breaking strain of the line in pounds. I tried this calculation on a
couple of my 2-Skewer kite designs, and it turns out the 20-pound
twisted Dacron we use is just right!
The rule of thumb is fine for wind strengths up to 'fairly
fresh'. If you have a homemade kite capable of riding out a gale, you
better double the line strength at least, before flying in those sort of
The more flying line you let out, the bigger the load the kite is
trying to carry, in addition to its own weight. Hence the lighter the
line, the higher the kite can fly before it reaches its weight limit.
The Less Billow The Better
We've seen how uneven billow can be a problem. Well, any billow at all
will affect the performance of most flat kites, whether left totally
flat or bowed or made with dihedral. The word 'flat' sort of gives it
away doesn't it! To illustrate this, one of my little Barn Door kites
became totally unstable after a lot of flying, when a bit of
stretch and / or slippage occurred in the sail. After tightening it up,
this homemade kite magically started flying well again.
Here lies one of the biggest advantages of special kite-making
sail material over thin plastic. The expensive stuff doesn't stretch
nearly as much!
There is one notable exception - the Delta kite. A conventional
Delta needs a certain amount of billow in its sail to fly properly. Another
exception is a tail-less variation on the Diamond kite which deliberately
introduces some billow near the tail end. This forms a kind of keel and
helps to keep it stable.
Multi-point Bridle Adjustments
Of course, if a bridle has lines going off to the left and right of
the kite, everything needs to be symmetrical. Or does it? I've found
it's very handy to make some of these bridle knots shiftable, so
if the kite goes left or right, you have another option for correcting
the problem. I'm talking about knots which can shift left or right
across the kite, rather than up and down as with adjusting the towing
Another reason for making them shiftable is so you don't have to
be perfectly accurate with tying a permanent knot in the exact correct
position. If a shiftable knot is off a bit, it's easy to slide it to the
correct spot! Also, I've never had a problem with one of these knots
shifting while the kite is flying.
That's about it for making a homemade kite which flies straight and high
over a wide range of wind speeds.
Original MBK 1-Skewer Delta
Original MBK 1-Skewer Delta
Hope you have a great time building and flying your homemade kite!
If you have already tried making a kite, and it has a disappointing wind range, check it off against all the points above. The solution might be simple, like tightening the sail a bit. Or you might discover you have a bendy spar on one side, and therefore have to make a new kite!
One little 'last resort' tip...
If your homemade kite has a tendency
to turn in one direction, and you can't fix it, try adding a tiny tail
on one wing tip! The faster the tip moves, the more it drags, so this
has a stabilizing effect. I actually did this on a 1-Skewer Delta to
trim it better. It was surprising how little tail was required, but it
certainly did the trick. There it is in the photo.
Down below is a photo of our much larger Dowel Delta kite. The leading edges are 1.2 meters (4 feet) of 5mm (3/16") dowel.
MBK Dowel Delta
MBK Dowel Delta
The video below is of our Dowel Rokkaku kite. This design is wonderfully
stable and predictable. Like the Delta, it is also a hoot to fly on
light wind days!
As mentioned earlier, there's more kite-making on this site than you can poke a stick at :-) Want to know the most convenient way of using it all?
The Big MBK E-book Bundle is a collection of downloads - printable PDF files which provide step-by-step instructions for many kites large and small. Every kite in every MBK series.