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I'd like to try to sharpen our vocabulary: in current use, "doubled die" is a generic term that does not specify whether the hub-doubing occured in the working die or upline in its working hub or master die. May I suggest we use "Hub-Doubled Die" when we mean that specifically?
Tom (and anyone interested in doubled-die Ikes), I think we're on the same wavelength. Please use the following to play off and continue this discussion here.
Would a sharply etched doubled image on a coin make a Hub-Doubled Die more likely than doubled master die? Would a working die down-line from a doubled working hub produce on an EDS coin a doubled image as sharp as that from a Hub-Doubled Working Die? (Granted this distinction would fade quickly in later die states.)
Looking at the wealth of similar doubled images cataloged as different in 71-S Silver Ikes, it's clear that the superior strikes of the SB Ikes (Silver Business strike) permits the identification and cataloging of a lot of "doubled die" Ikes that are slightly different. Ditto 71-S Ike Proofs.
Since all the working dies for 71 Ikes came from the same pool of dies, this must be the reason there are so few 71-P and 71-D doubled dies, right? If this thinking is correct, would not any strongly doubled 71 or 72 circulation Ike have been struck with a Hub-Doubled Die?
It seems reasonable that "similar but slightly different doubling patterns" that show on Ikes downline from doubled master dies are to be expected since that doubled master die in turn produces working hubs that in turn produce working dies: each subsequent hubbing would/could introduce subtle changes in the doubling pattern. That's why I want to thoroughly work out whatever up-line doubling patterns we can attribute specifically to master dies and working hubs.
Otherwise, we'll contine to accumulate and catalog more and more Ikes with slightly different hub-doubling.
On a related topic, It's probably a fact that master dies were carefully checked for major doubling and discarded if present.
Working hubs were probably not subject to such close inspection, yet major doubling probably would have been looked for and examples discarded.
Thus, the most dramatic hub-doubled Ikes are probably due to Hub-Doubled Working Dies, right?
Also, that most Ike hub doubling is rotational ("Class II") probably stems from the absence of keyed blanks (I think they had a flat ground in but only a "key" would assure proper alignment automatically): for hubbings after the first, the hubbee was probably marked with a pencil to align it in the hubbing press, just the way die setters at the Mints marked the die pairs with a pencil so the dies could be aligned properly in the coin press. Rob
Hi Rob,Also, that most Ike hub doubling is rotational ("Class II") probably stems from the absence of keyed blanks (I think they had a flat ground in but only a "key" would assure proper alignment automatically): for hubbings after the first, the hubbee was probably marked with a pencil to align it in the hubbing press, just the way die setters at the Mints marked the die pairs with a pencil so the dies could be aligned properly in the coin press. Rob
I think most doubling occurred when a working hub was used to make a working die. Also an added factor is the possibility that a finish (or different hub was using in a second or third press) in order to bring up the details of the die. A very well used hub could have been used in a first press with the details sharpen with a second press from a new or better hub. It is a common practice in industry to use a different/finish tool to do the finish pass or to do the fine details.
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