2007 doubling on ear

[931louis]

I'm trying to get a few opinions on this.

[wavysteps]

Neat looking, but I am affraid it is machine doubling.

BJ Neff

[Novicetoerr]

2007 doubling on ear

Please briefly explain why this 2007 doubling is different from the referenced
1997 and 2006 doubled ear coins? Also the Cause differences?

http://koinpro.tripod.com/Articles/1997DblEar.htm
http://www.varietyvista.com/2006PDDO...tm#Photographs


Thanks,
J

[Steven]

Here is a very good reference site that will answer many questions about doubling etc.

http://www.bakercoins.net/learn/variety/ddie/class1.htm

[Novicetoerr]

Here is a very good reference site that will answer many questions about doubling etc.

http://www.bakercoins.net/learn/variety/ddie/class1.htm

Greatttt!

Thanks Steven!

Now let me provide my analogies of the 3 doubled ears mentioned in this thread.... in layman's language. Let me know if correct :

2007 - Totally agree this is MDD. The external flat separation in external
part of ear was caused after punch.

2006 - Mmmm....Being a novice, at a glance, can't even say there is
doubling. I will need another 006 reference coin with no doubling
for visual comparison of the earlobe sizes. I'll assume the bottom lobe
increased the size of the ear. So it's DD.

Please provide your analogy (without use of ref. coin) why it is a DD.

1997 - Mmmmmmm... Moremmms. Again as novice, can't easily tell.
Looks borderline to me at first glance of the separation.
A closer look reveals lobe is raised metal, so I'll assume DD.
...But MDD doesn't always mean flat doubling images???

Steven,
Can you now give your analogies of the three, how to arrive to the
3 conclusions?

Many thanks!
J

[Novicetoerr]

Here is a very good reference site that will answer many questions about doubling etc.

http://www.bakercoins.net/learn/variety/ddie/class1.htm

I believe that the site is not updated with what I've been hearing regarding the old tech multiple vs single squeeze hubbings. What DD 's can only be expected from the single squeeze.

Which of this web topics need to change? DD's only while rest of
topics will still be applicable?

Thanks,
J

[Steven]

1997P Doubled Ear: Class 4 Offset hubbing and Class 8 tilted hubbing. I believe this is caused between hubbings.

2006P Doubled Ear: Offset hubbing. Class 4. I understand this to be the die shifts between hubbings in a particular direction without rotation.

2007 Mechanical Doubling Damage. This is not caused after the strike as you have stated but during the strike with loose dies causing the damage during a shift in the dies.

Definitions of each of these are refenced in detail on the link I previously posted. I am sure that it will give you better explainations than I can pull off the top of my head.

[Steven]

I believe that the site is not updated with what I've been hearing regarding the old tech multiple vs single squeeze hubbings. What DD 's can only be expected from the single squeeze.

Which of this web topics need to change? DD's only while rest of
topics will still be applicable?

Thanks,
J

I feel that the author put together an excellent site with detailed information. I agree that the Class 9 doubling is not referenced concerning doubled dies with the single sqeeze hubbings. The only explaination I can come up with for the hub doubling during the single squeeze is possibly a shift during the squeeze causing a thickness of the devices or possible more than one squeeze causing notching shown in many class 9's. There are also other classes of doubled dies created from the single squeeze process reported.

Maybe BJ can jump back in here and let me know if I am on the right track with this.

[wavysteps]

To add my two cents in (no pun intended) there is a difference in the single squeeze hubbed doubled die and the multiple hubbed die,sometimes.

When we look at the single squeeze hubbing, we first must determine if it is continuous hubbing or non-continuous hubbing. The difference: continuous hubbing is when a the die is made in one application, without stopping the process. If a doubled die is created during this continuous hubbing process, the correcting factor is the pressure applied by the hub to the die, which will reposition the die to the correct attitude in relation to the hub. This will cause a smearing affect, but still create two (or more) images. The intensity of the secondary image to the primary image will be in direct relationship to the stage the hubbing process is in; the earlier the stage, the less the secondary image will be impressed, the later the stage, the more the secondary image will be seen.

The non-continuous single squeeze hubbing is a bit different. It starts of normal, however, due to a positional offset between the hub and the die face, the hubbing is stopped and the die re-positioned manually. This will occur after the initial first "kiss" of the hub against the die face, which will leave an impression. The subsequent hubbing (s) will leave another impression of the same design element, but in a different location. Most if not all the "extra" columns and "extra" parts of the reverse Lincoln statue on the Lincoln cent are from non-continuous single squeeze hubbings. I also imagine that the same scenario applies to the "extra" parts of the ear lobe found on the obverse of some denominational coins.

To understand what is going on with these multiple hubbings, one must have a clear idea of just how this hubbing system works and what can go wrong. People like Ken Potter, James Wiles, John Wexler, Chuck Daughtrey, Bob Piazza, Billy Crawford and myself have put countless hours in studding and trying to figure these systems out and through our collective knowledge, we have. Yes, there are areas that are a bit fuzzy, however, give us time and we will find the answers

BJ Neff

[Novicetoerr]

1997P Doubled Ear: Class 4 Offset hubbing and Class 8 tilted hubbing. I believe this is caused between hubbings.

2006P Doubled Ear: Offset hubbing. Class 4. I understand this to be the die shifts between hubbings in a particular direction without rotation.

2007 Mechanical Doubling Damage. This is not caused after the strike as you have stated but during the strike with loose dies causing the damage during a shift in the dies.

Definitions of each of these are refenced in detail on the link I previously posted. I am sure that it will give you better explainations than I can pull off the top of my head.

Thanks Steve, BJ!

Have re-stated here Steven's 3 analogies. But can you expound on each analogy --->by describing the characteristics of each respective image, that led to each conclusion.

Thanks!
J


1997P Doubled Ear: Class 4 Offset hubbing and Class 8 tilted hubbing. I believe this is caused between hubbings.

2006P Doubled Ear: Offset hubbing. Class 4. I understand this to be the die shifts between hubbings in a particular direction without rotation.

2007 Mechanical Doubling Damage. This is not caused after the strike as you have stated but during the strike with loose dies causing the damage during a shift in the dies.

[Steven]

Thanks Steve, BJ!

Have re-stated here Steven's 3 analogies. But can you expound on each analogy --->by describing the characteristics of each respective image, that led to each conclusion.

Thanks!
J

I would say BJ answered your question very well.

[Steven]

I must stand corrected in my previous post I indicating that MDD happens during the strike. It is post strike and thereby considered damage as I have found through reading available information. I should have gotten more points of reference prior to posting. My appologies for posting incorrect information.

Now the beatings may commence.

Steven

[Novicetoerr]

2007 doubling on ear

Steven,
Will forgive you after helping me out on this doubled ear thingy...

- There was a comment on a previous thread that there was no
known 1999 Doubled Ear. But this 1999-P cent coin on my collection jar
is screaming to check it out for ear doubling abnormalities.

So here it is... Have identified an ear doubling (maybe I'm really confused).

Thanks,
J

[mustbebob]

Steven,
If I am reading this thread right, you had it right the first time. Mechanical doubling does happen DURING the strike....not post strike. A loose collar, loose die, mechanical mis-adjustments etc contribute to the doubling. It is still considered damage by many folks, but it does happen during the strike. Anything happening after the strike would just be considered damage.

J....as far as your 1999 cent, there is no Hub doubling or abnormalities on the ear. You will find that earlier die state coins show more detail in the area you show. If you wish, I will post a pic of a 1999 coin I just picked out of a pile that looks pretty much like yours. Looks like normal design elements to me.

[wavysteps]

Ah!, the old question when does the strike end? According to Hoyle (Alan Herbert) as soon as the die begins its retreat from the coin surface is when the strike ends. So, looking at that statement, machine doubling occurs after the strike.

Of course there are a lot of arguments for and against this "when the strike ends" and it has even spilled over to "when the hubbing ends", which is even more complicated when one thinks about it. In the long run, it is the understanding of what is happening that creates the anomaly and not the moment of creation that is important.

BJ Neff