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<p>[QUOTE=&quot;CaptHenway, post: 5132150, member: 13813&quot;]I am sure that the &quot;Blakesley Effect&quot; was written up in Coin World&#039;s Collectors Clearinghouse in the 1970&#039;s, either by Jim Johnson before he retired in 1974, by Ed Fleischmann before he left to go work for ANACS in 1976, or by myself before I left in 1978. </p><p><br /></p><p>The Blakesley Effect is a multi-step process. It must be preceded by the creation of a flat blank with some metal missing along the edge in one or more places. This void (or voids) is typically caused by the blanking press creating overlapping holes (a standard clip), or by the blanking press overlapping a straight edge on the strip (a straight clip), or by the blanking press overlapping a rough void in the strip (a ragged clip).</p><p><br /></p><p>As the incomplete blank is passed through the upsetting mill, the proto rim is formed by the opposing pressures where the diameter is complete from one side to the other and not formed where the diameter is incomplete. This is the Blakesley Effect as seen on an unstruck planchet. In the case where the voids are very minor, partial upsetting may occur.</p><p><br /></p><p>During the normal upsetting process the diameter of the planchet is reduced slightly. I have measured Type one Blanks and Type Two Planchets and the difference is very minor, but measurable. Where the non-void side of the blank is not squeezed inwards to form the proto rim, the non-moved metal may appear as a very minor &quot;bulge&quot; since the metal on either side of it was moved inwards, but I would not expect it to interfere with the planchet feeding into the collar or survive the strike.</p><p><br /></p><p>During the strike the force of the press will attempt, and typically fail, to reshape the non-upset area of the planchet, the Blakesley Effect, into the rims on the dies. The amount of reshaping that is accomplished depends on the metal involved, the relief of the dies and the pressure setting on the press. The result is typically a coin that shows a Blakesley Effect that survived from the planchet preparation process.</p><p><br /></p><p>TD[/QUOTE]</p><p><br /></p>

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