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<p>[QUOTE=&quot;Kevin Mader, post: 3972384, member: 106826&quot;]My speculation: When it comes to lathe marks, the error can be anywhere in the field of the coin (and typically it is rather than a single mark like we are seeing here) and generally concentric based on the images at the site Paddy provided.&nbsp; I suspect that if there is a deeper &#039;groove&#039; left by the lathe and not adequately removed, then the conical rod that&#039;s made into the working dies will have that minor defect (note: during the turning process, I suspect that they may make a few passes to create the conical section and depending on speed/tool condition, the finish will be different).&nbsp; During the squeeze (between master/conical rod), I suspect minor grooves created during the turning process (or not adequately removed during finishing) are obviated.&nbsp; But the deeper ones are not and make it into the design of the working dies.&nbsp; I think this is what we are seeing here.&nbsp; Dull/chipped tools may have been the culprit.</p><p><br /></p><p>As for the mark being centered, it may be associated with the way they press the master die into the working die.&nbsp; I know that there is some play that may cause a mark like ours to drift a bit NSEW and could be exacerbated by the angle of the master as it is pressed into the conical rod.&nbsp; I know that this movement is what affects the working dies in the creation of the minor DDOs/DDRs we are seeing.&nbsp; It would be interesting to hear what some of the experts think is happening.&nbsp; I must agree with others that I&#039;m necessarily satisfied with the answers I&#039;ve been given or read including my own theory as to how it might have happened.[/QUOTE]</p><p><br /></p>

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