Are there any examples of Master hub doubling?

DHeath

One of you who has studied more that I can help me with this question. As I understand the Hub/Die relationship, the master hub(raised relief) is used to create the master die(incuse) by means of multiple strikes into an annealed die rod. Once cut from the rod, the master die is hardened and pressed into annealed working hubs. The working hubs require multiple impressions too. Now the question, is hub doubling only documented in the working hubs, or does it exist in a particular master hub?

coppercoins

1957 cents....all of them have doubling to some degree (depends on the condition of the master hub at the time the master dies were created) on the "D" in "GOD".

1961 cents....all of them have doubling on the top of the "OD" of "GOD".

1939-196? nickels - all of them have minor doubling on the obverse.

1951 quarters ALL have minor doubling in the motto (IGWT).

That's all I can think of for now.

keoj

Boy, this is an excellent question! For the series that I collect, I'm not aware of any doubled master hubs but that doesn't mean that they don't exist. I am aware of a DDR that was made with two master hubs however (meaning the working hub was struck with 2 differnt masters). Hope that this helps.

keoj

DHeath

Thank you, CD. I hadn't seen that in print anywhere, but I thought there must be. I should be almost impossible to properly realign the master hub and die after annealing every time. I'm surprised it is not a more common phenomenon.

Keoj, do you mean that during the process, they switched dies?

coppercoins

Well, now that I think of it, and correct me if I'm wrong, the first stage where hub douling can take effect would be at the "master die" stage. The "master hub" is created at the janvier lathe, no?

galvano - dipped - hung on lathe

reduced to master hub -

-- creates master dies -

----- creates working hubs -

------- creates working dies -

------------- creates coins.

Since the "master hub" is a lathed copy of the engraving, there wouldn't be any doubling that wasn't on the engraving, no?

DHeath

CD, you're right, it would have the be the master die.

Dog97

There are 3 different Morgan designs from a doubled hub. The III2 obv which includes all Morgans from 1879 to 1904 have a doubled N in UNIM as does the C3 from the same years with the M on the rev bow being doubled. The C4 rev with doubled letters in DOLLAR & AMERICA in 1902, 03, & 04. These were caused by misalignment between the hub & the master die and also at a lower step in the die making process by misalingment between the master die and the working hubs which in turn created the doubled working hubs of course leaving a doubled image on the working dies.