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<p>[QUOTE=&quot;Clawcoins, post: 3363622, member: 77814&quot;]some excerpts from the alternative metals document ...</p><p><br /></p><p>·&nbsp; The Philadelphia and Denver facilities frequently have different production experiences with the same coin design.</p><p><br /></p><p>·&nbsp; Currently, all coin designs are modeled and digitized, or produced digitally.</p><p><br /></p><p>·&nbsp; Master dies are prepared on digitally controlled milling machines at the Philadelphia facility.</p><p><br /></p><p>·&nbsp; After heat treatment the master dies are used to impress an inverse of the design into another piece of heated die steel, the hub.</p><p><br /></p><p>·&nbsp; After additional heat treatment, the hub is pressed into another steel piece to produce a working die that will be used in a coining press.</p><p><br /></p><p><br /></p><p>·&nbsp; Master dies are distributed to the Denver facility, which produces its own working hubs and dies.</p><p><br /></p><p>·&nbsp; Despite using the same masters, the crown heights of dies and <u>design heights of relief produced at the two facilities differ</u>,</p><p><br /></p><p>·&nbsp; 138 which has a measureable effect on coin fill. Further research into the reasons for this difference and its impact on die life, coin quality and production costs is warranted.</p><p><br /></p><p><br /></p><p>·&nbsp; Consistently high one-cent coin die failure rates significantly affect overall production costs.</p><p><br /></p><p>·&nbsp; Average <u>die life</u> in 2009 reached a <u>low of approximately 300k strikes</u> at both the Philadelphia and Denver facilities.</p><p><br /></p><p>·&nbsp; Since <u>one press produces roughly 300k coins in one 8-hour shift</u>, this failure rate reduced production efficiencies and costs from historical trends.</p><p><br /></p><p><br /></p><p>·&nbsp; Note that one-cent coin die life from 2000 to 2008 averaged 1 million (M) hits, but that has fallen to under 500k from 2009 through 2011.</p><p><br /></p><p><br /></p><p>·&nbsp; In the Philadelphia facility there are seven presses in one production cell for one-cent coins, and a single operator manages six or more presses at one time.</p><p><br /></p><p><br /></p><p>·&nbsp; Desired production rates rely on any six of the presses being in operation at any given time. Therefore, if one press is down for a die change or for some other reason, these production rates are not impacted. At the Denver facility,</p><p><br /></p><p>·&nbsp; however, the production rates rely on all presses to be operational at all times; therefore, an increase in the frequency of die changes can be more disruptive. An average die life of 600k or more strikes (1M strikes or more for one-cent dies) would be beneficial for both sites.[/QUOTE]</p><p><br /></p>

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