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<p>[QUOTE=&quot;rmpsrpms, post: 3504827, member: 31773&quot;]Another &quot;hole&quot; is actually the space between the upset edge of the planchet and the collar. The highest pressure areas are where the fields are coming together. Metal must flow from within the bulk of the planchet to fill the devices, and it must also flow outward from the bulk until it is constrained by the collar and the die rim. At that point the only unconstrained part is the small gap around the perhiphery of the die, and at some point with strong enough striking force this area will form a &quot;wire rim&quot;. Usually the machinery is adjusted so this does not happen, since excess striking force shortens die life. </p><p><br /></p><p>In my extreme example of having no devices to fill, the only movement is outward. When devices are present, some metal will flow into them, causing some net inner movement at the die surface near those devices, but there will also be a net movement near the the edges of the coin similar to the case with no devices. Somewhere in the middle, depending on the relative volumes that are being moved, there will net zero, though vs time that net zero will probably move, supporting your correct contention that there is always some movement in all areas of the die surface.[/QUOTE]</p><p><br /></p>

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