Simple ratio needed
TN65X57
Seemed like it would have been easy to find!
The concept is too simple for todays world.
Any help appreciated!
LouisB
The Silent Observer
I've seen a number of plans where the cross spar is the same length as
the spine. For my tastes, that makes a kite that's a bit too wide, but
they do fly well. I prefer about 4:5 for cross spar to spine ratio on
the bowed Eddy, aka Malay. For those kites with the forward curved
cross spar, use the same sail proportion, but size the cross spar to
hold the proper curve, tangent to the leading edges of the sail just as
it enters the pockets at the corner.
Then there's the question of how high on the spine to put the cross spar
-- on the bowed Eddy above my computer, I've built it about 1/3 of the
way from top to bottom, but you'll find the kite flies well anywhere
from about 15% to 40%, just as you'll likely find width to length ratios
anywhere between even and 3:5 will fly just fine.
It's largely a matter of what looks right to you; if you build the kite
straight (so the sail is symmetrical across the spine and the cross spar
bends the same amount in the same locations on both sides), and put a
reasonable amount of dihedral in it, and adjust the bridle to the kite
instead of expecting a fixed ratio to be right, you'll find nearly
anything that looks like a diamond kite will fly like one.
--
Love wealth above life itself, and starve in splendor.
-- Elvish proverb
Donald Qualls, aka The Silent Observer NAR # 70141-SR Insured
Rocket Pages http://silent1.home.netcom.com/launches.htm
Telescope Pages http://silent1.home.netcom.com/astronomy.htm
Lathe Pages http://silent1.home.netcom.com/HomebuiltLathe.htm
Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.
kitebuilder.com
can find several plans for this kite at www.kitebuilder.com. Look in
the Plans section under flat and bowed kites.
The basic dimension is: The kite is as tall as it is wide with the
horizontal crossing the verticle 20% from the top. The kite should be
bowed at least 10% of the spar length. On smaller kites you might
want to go to 15%. You can achieve this dihedral with a fitting, a
bow line, or a bowed spar. Use a two point bridle off the verticle
with a line about 1.5 times the spar length.
You will discover different ratios from different kite builders, so
dont be afraid to experiment with your own modifications.... If the
kite turns out to be a little unstable, add a tail!
Good luck and keep us posted on you progress...
~Steve
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www.kitebuilder.com
Go Build a Kite.
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"Two Stick"tn6...@aol.com (TN65X57) wrote in message news:<20020801183940...@mb-de.aol.com>...
Pierre Gregoire
I like to use twice the width for the height (or I guess half the height for the width) and 12.5% as the crossing point.
Therefore a diamond (eddy) I made was 96" (2x48 1/4" or 5/16" wood dowels) for the spine (vertical) and 48" for the horizontal spar (1x48 1/4" or 5/16 wood dowel). The cross point for this kite was at 12" measured from the top of the spine.
The bridle is a 3 point (i use a 4 point cascade, which is overkill). The two upper bridle attachment points on the horizontal spar being 12" (half way) from the spine, the upper bridle legs being around 36" each or a total length of 72" (long enough, so that the V formed meets the vertical attachment point). The vertical attachment point is 46" from the top of the spine.
The bridle adjustment is like a Rokkaku and the horizontal spar is bowed like a Rokkaku also. So you will have a left-right adjustment component (prussik knot at the V) and an angle of attack component (also a prussik knot) for the attachment point. The length of the leg from the V to the vertical attachment point could be ( I just eyeball) the same length of the leg that forms the V (in the above example 72", you can never be too long).
This kite will not require a tail, since its length to width ratio is I guess 2:1 or is that 1:2.
Most of the flying surface is right at the top, the rest is really a disguised tail.
I got this idea from attending one of Ron Gibian's kite building classes. Ron makes a kite called an Astroglider, that is even more low aspect ratioed.
When the kite flies, there is hardly any tension on the lower bridle point along the spine.
Hope that helps,
Pierre
ps: I've made smaller versions, such as 24" wide,
48" long, also 12" wide and 24" long,
they all seem to work okay.
