Years 2005 - Now , Jefferson Nickel - Liberty Study

OK, NUMI,

I will PM you, you give me work to do. How many Kilo you need?

@Numidan, I understand what you hope to accomplish. As a learning tool it is great to be able to see the differences between actual DDOs and other forms of doubling. I thought it might help to show you some excellent photos of a couple of well-known DDOs and let you view them up close. The first is the famous 1972 Lincoln Cent DDO (FS-101). If you move your mouse cursor over the word "Liberty", you will get a close up of what the doubling looks like. Also note the date and the words "In God We Trust". This is a well-known and dramatic doubled die in a modern cent. https://www.PCGS.com/coinfacts/coin...101-rd/38013

The second is the 1995 Lincoln Cent DDO. Again, focus on the "Liberty". Then look at the "In God We Trust" and you'll see doubling. This shows that doubled dies can appear different, based on the class of doubling and the characteristics of each doubled die coin. Different years may look different. But there are features that are quite visible. Many of us look for the "spread" in the letters or numbers. Also, split serifs in the letters and numbers are key findings. https://www.PCGS.com/coinfacts/coin...101-rd/38105

Unfortunately, the best way to really see the difference is to hold one in your hands and look at it closely. Because the 1995 is far more plentiful, it doesn't cost all that much to buy one. According to PCGS, you should be able to buy a 1995 Lincoln Cent DDO FS-101 in MS64 condition for about $35. I often think I learned more about what to look for after I bought my first one. If you're interested, here is a link for an uncertified one on L&C Coins that is priced at $35.
https://www.lccoins.com/default/199...65red-1.html

Although they say a picture is worth a 1000 words, I agree a picture does not always reflect what you are seeing. Macro photography is very challenging especially when taking a picture of a coin having a reflecting surface! The small details tend to get lost in the highlights and shadows of the image, where intensity values are close to 255 or 0.

But, having any pictures does help in a study. It provides a better distribution of what is circulating out there which would be impossible for me to obtain!




Ultimately, it is what I would like to accomplish. Understand how the changes to the US nickel's design has affected die and striking errors.

Why concentrate on the word "Liberty"?

Reading the many posts here and on other sites, people and including myself are curious in understanding the reason(s) for the doubling on the word "Liberty".

If no member participates, it will not have the same impact but I am fortunate that Silviosi has reached out giving me access to US nickels to do my study. It will take time but I will reply to this post as my study progresses.

Thank you.

The facts

There are two major design changes that has a direct impact on material flow and stress distribution during the hubbing process of the working die and the minting of the coin.

To minimize stresses and extend the life of a working die, ideally, you want the working die to initiate a contact at the center of the blank and progressively distribute the pressure towards the rimmed edge. This is obtained by having a curved field and an axisymmetric design.

The US mint has designed a new obverse for Jefferson nickel having characteristics that do not follow normal design characteristics enumerated above.

The image below shows the difference in symmetry for type 1, type 3, and type 4 designs. You can clearly see that types 3 and 4 do not respect axisymmetry.



The sketch below shows the different curvature of the field for type 1 and type 4 (same for type 3) designs. You can use your 10x magnifier and observe this difference. Types 3 and 4 have a flatter field compared to type 1.




The Study

How will these changes affect metal flow and contact points that create the doubled die and metal flow and the stress points that leads to die deterioration?

In the single-squeeze hubbing, the working die blank is placed into the well of a collar and the hub is resting on the conical point of the working die blank as shown below.

Since the diameter of the well in the collar exceeds the diameter of the working die blank and the hub, there is "play" in the collar well.
source:https://doubleddie.com/58222.html



I am theorizing that since the Jefferson image is off centered, there is a greater possibility for the working die blank and the hub to be misaligned compared to an axisymetrical design.

Because of this slight tilt, during the hubbing process, there is a possibility of the hub making a premature contact with the working die blank as shown below.

As hubbing process continues, there will be a vertical alignment in the collar well and as the die/hub gradually slides into place, this will cause a doubled die. (Note: the the bottom sketch is hypothetical! I wanted to show how far the contact point is as both the die/hub is realigned graphically.)



I am currently learning how to perform finite element analysis to try to prove this in a simulation.

Me I go different.

So I will state for what is state the words
V =very
E = Early
M = Middle
L = Late
D =Die
S =States
Ex = extremely

So me I use :
1. category 1 = a. VEDS, b. EDS and c. LEDS
2. category 2 = a. EMDS, b. MDS and c. LMDS
3. category 3 = a. ELDS, b. LDS and c. VLDS.
4. category 4 = Ex. VLDS
On your coins IMHO you has 1b, 1c, 2b, 2c and 3c

Here are pictures of various die chip and die crack found in the lot.

Wexler has images of the 2004 DDO that I've used in the past:



But side by sides, shows how the spread affects differently on the normal and DDO's on this 2004 1 DDR cent.

That way everyone can see the differences in size of the doubled dies. (Sorry I don't have examples of the 2004-P nickel DDO. But seeing them side by side is more convincing.