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<p>[QUOTE=&quot;ToughCOINS, post: 2309060, member: 20480&quot;]I&#039;ve touched on this subject in other threads.</p><p><br /></p><p>Coin design is not just art . . . it is engineering as well.&nbsp; In this particular case, no attention was devoted to the amount of material that had to be raised at coincident real estate on opposing sides of the coin.</p><p><br /></p><p>Good design dictates that, inasmuch as possible, the relief on one side of the coin avoid the relief on the opposite side, such that the cross sectional area of the void where the planchet metal must flow between the dies is not too large, or the material will be insufficiently constrained, so the pressure in the metal drops, and the metal will not fill the dies . . . for fluid engineers (civil or mechanical), this is analogous to open channel flow.</p><p><br /></p><p>When designs such as that above are implemented, the striking pressure must be extremely high to impart full design details upon the coin, compared with better designed coins of the same size and material.[/QUOTE]</p><p><br /></p>

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