Sagaies en sureau et propulseur en chêne

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Redbow
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La méthode de mesure du spine (rigidité) vient de Tom Mills :

Making a Rivercane Atlatl Dart


(The over all length of the finished dart is 89″ (81 1/2″ shaft – 7 1/2″ fore-shaft).)
“Take the straightened shaft and push it down on a bathroom scale. Note the poundage when the dart just begins to flex. If the cane flexes between 5 – 7 lbs, great. If less than 5lbs, shorten the shaft by trimming from either end (try to keep the nock located on a node, however). If the spine is way over 7lbs, it will usually fly poorly. Once you make a few darts, you’ll get the feel for selecting proper material at the outset. If trying to make a matching set of darts, pay more attention to the spine weight than to the length of the darts themselves. If your dart is spined a bit too heavy, you can adjust it by making a longer, heavier fore-shaft. Again, the bathroom scale test will not be affected by adjustments to the mass of the point – you’ll only see the difference in flight tests.”