Dart Design Guidelines:
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Preferred weight of a cal .62 Dart is 3.2 gramm (however darts 0.5 to 5
gramm can be used)
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Above darts perform best (waggle free) when fired by 2.2 Meter Blowgun,
fired with a strong blow -> muzzle speed about 48m/s
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The dart must have the major part of the weight in the first half of length.
The Point of Balance also known as "Center of Gravity (CoG)" shall be located
always less than 50% of length (measured from tip). If CoG exceeds
40% then problems with waggling of dart will increase much.
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Tapering the shaft ensures that most weight is located in the first half
of length.
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Cone must be kept as light as possible ( lees than 0.7 gramm)
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Above darts have a cone with a slope of about 3 : 1 ( Length : Diameter)
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Initial the the cone is made with 9 fins that are too long (15 mm) , they
are cut off to optimum length later on.
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Fins may have a parallel shape (as far as possible)
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The end diameter of cone at the end of the fins shall be close to
95% (+-2.5%) of cal of blow gun (exceeding 100% of cal. leads to overcompensation
of the dart)
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The average gap width between two fins shall be 1.1 mm (+-0.2 mm) -> for
cal .62
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Flexible fins do auto adjust during flight (they bend under streaming air)
and can be used for a wider range of speed. Two layers of 0.1 mm Polyester
(PET) Film is best. A cone rolled with 3 or 4 layers of film will be extremely
stiff. Extreme stiff (thick) fins do not bend during flight their capability
for waggle compensation is higher, but the cone can only be used for a
smaller speed range.
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