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 Replies: 23 / Views: 6,645 |
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Pillar of the Community
 Canada
1622 Posts |
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Pillar of the Community
Canada
4911 Posts |
i'd say quite confidently that your coin is legit..nice example! as SPP stated, this is the most common year to find this error on dollars..however that doesn't mean they'r all that common either. I'm still looking for an example..enjoy yours!  Feel free to call me Will.
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Moderator
 Canada
10460 Posts |
Most definitely legit...
"Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
 Canada
5591 Posts |
I really don't see how that could be pre-mintstrike. Once struck, metal would flow into the "wound"
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Moderator
Canada
10460 Posts |
The metal is not a fluid... why do you think they burnished the planchets for Proof-like and Specimen strikes? To reduce the marks on the planchet surface prior to the striking...
"Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
Canada
5591 Posts |
I realize that the metal is not "liquid", but there would be some displacement of the metal into the "gash", as shown on the edge. The edges took too sharp and crisp with no displacement from the die being struck.
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Moderator
Canada
10460 Posts |
Did you not see the partial cut of the planchet on the rim edge? Of course the edges are sharp, the planchet cutter (punch) creates pretty sharp cuts...
"Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
Canada
5591 Posts |
As you know, SPP, I am not an error collector but, rather, just an engineer who questions how things are done or put together. I KNOW that the planchet cutter is very sharp. I just can't figure out why, when the planchet is struck by the dies, some of the sharpness is not distorted/peened over or somehow else distorted. It looks like the "cut" happened after the coin was struck, going cleanly through the edge roll, the rim, the beads and the rest of the coin.
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Moderator
Canada
10460 Posts |
Because the dies are slightly concave (to promote faster ejection and less sticking, i.e., caps). Being slightly concave, the press produces a radial force from the centre of the planchet outward (which gives us cartwheel lustre). That radial force is equal in any and all directions (in the horizontal plane along the surface of the die) which is orders of magnitude less than the vertical force. Therefore if there is distortion across the face of the coin, it will be radial in fashion and distortion will be equal everywhere from the centre of the coin to the rim. That deep cut was there, before the strike, on both sides of the coin. It survived the rimming phase (which, where they sometimes do separate and create "football clips"). The rimming phase does "pinch" the partial clip a bit, but when the dies struck the coin, there was not enough metal to pull into the devices (on both sides - equal and opposite forces at play here) but elsewhere, the metal did pull into the devices, more so on the anvil die. When you look at the devices where they intersect that cut with a 10x or stronger lens, you see that it is not a sharp, post-mint cut, but a short thinning. Sort of like how rims dovetail into a clipped coin. The blanks are not cut entirely. If you examine the edge of a clipped coin or a Type I planchet, you see that the blank is partially cut, then the rest is removed from the rolled metal sheet by shearing. In these examples, the cut was made, but not sheared off the rolling stock. Someone then readjust the strip feed and the blanks were then punched, again, incorporating the partial cuts. Sometimes one side will be sharper (cutting side) than the other side (shearing side). I took engineering in school too Bill, for almost three years... but I found it too boring, so I switched to geology!!  "Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
Canada
5591 Posts |
Well, I just made ships run and knew how to repair them. I was a Naval (Marine) Engineer with a degree in mechanical and spent nearly 20 years (of my 31 in the military), either at sea or running/working a shipyard as an officer ... after 10 years in Electronics (my enlisted rate). Now I just collect Vickies and ask questions on coin sites.
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Moderator
United States
23522 Posts |
Here's some relevant reading: http://www.error-ref.com/incomplete-punch/Pay particular attention to the Cent blank at the bottom, illustrating just how broad and deep the incomplete punch can be before striking. It helps one to understand how much of the original semicircle is obliterated by the strike, and why the details on the struck coin appear as they do. |
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Moderator
Canada
10460 Posts |
Here is a fun one... an incomplete clip, and a clipped planchet, all in one coin.  "Discovery follows discovery, each both raising and answering questions, each ending a long search, and each providing the new instruments for a new search." -- J. Robert OppenheimerContent of this post is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. See: http://creativecommons.org/licenses...0/deed.en_USMy eBay store
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Pillar of the Community
Canada
1622 Posts |
Very cool!
And thanks for the explanation SPP
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Pillar of the Community
Canada
1622 Posts |
Update. I put 'incomplete punch' on the order form, but...  Edited by johnnysprawl
08/20/2018 9:21 pm
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Bedrock of the Community
United States
74813 Posts |
Johnnysprawl, that's an awesome error coin! It looks great in that slab!  Errers and Varietys.
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Replies: 23 / Views: 6,645 |
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Posted 12/10/2017 12:40 pm
