One is Two: A double die from a single squeeze?

[notabot]

Can an expert tell me just how it happens that two columns, dates, Liberty, or other element appears on the coins during a single squeeze.

[Bob P]

Hold on to them veins notabot. Theories abound on how we are getting these doubled dies. The most prevalent and agreed upon theory is what they call the 'snap back' or shifted hub theories. It supposes that when the hub is lowered to impress the master dies, the alignment is not perfectly level. As pressure is continually applied, the hub snaps back into proper alignment, producing the primary image. Chuck's book describes it like this: ' This form of doubling is often characterized by a slippage of the design, often the center devices, in a cardinal direction. The main difference compared to class 4 (offset hub doubling) is that the design is never picked up off the die during hubbing, but rather it suddenly slides into place, creating the doubling in the design'.
That being said, there are instances where the die is hubbed more than one time resulting in documented class 4 varieties. Those are the 2006-1DO-017 and 018 dies, the doubled die Peace nickel, and two cases of 2004 reverse doubled die cents. This can happen when the initial 'single squeeze' does not produce the desired results, and subsequent hubbings are warranted.

[coop]

Well I've wondered if there was some play between the hub and die. Kind of a mechanical doubling that makes a sloppy hubbing. The reason I think this is that most (Not all) of the doubled die Cents in 2006 were from the Philly mint. Seems that something wasn't working correctly and there were so many different doubled/single squeezed dies. They were even installed at the same time producing murphy's boxes that he several different doubled dies in those rolls from one box. So that senareo has we think on that possibility.

[notabot]

Gotta love Rodney.

[wavysteps2003]

The single squeeze doubled die. First, let us take a look at the statement made in 1986 by the MINT. "It will also avoid the possibility of hub-doubling errors caused by misalignment of the second squeeze". If you will notice, the MINT does not say that it will stop doubled dies from occurring, however, this statement has been mis-interpreted into believing that all doubled die would cease.

As to Coop's question. This is another statement from the MINT, recently acquired. "there is horizontal movement (hub to die) not only at the end but throughout the entire hubbing process cycle". This was in response to one of the question concerning the formulation of my wavy step/trail theory.

The possibilities that single squeezed dies are re-hubbed or multiple hubbed. There are conflicting reports concerning this practice, from very reliable sources, with one side saying it does happen and the other saying that it doesn't. There is a possibility that with some of the stronger type IV doubled dies that are made from single squeeze, that there could have been slipage to cause doubling of design elements in this mid stage of hubbing. However, one would think that when the keys on the die begin to form (from the slots on the hub), any possible slipage would end between the hub and die until after completion of the hubbing process.

There is one other possible scenario to cause a doubled die in the single squeeze process and I believe we saw this on some of the wider spreads on the OIV nickels and Minnesota / Oregon quarters. This is where the hub center to die center is out of alignment and is corrected not by pressure but by the hub press operator, however, only after the initial first "kiss" of the hub to the die. These are being classified as Class VIII (tilted hub) doubled dies, which seems to be a very ill fit for the definition of that particular doubling. When trying to apply this Class VIII doubled die to single squeeze hubbing, we are being led to believe that the hub can be tilted to the angular degree of the coniclal slope of the new, unformed die. This is not going to happen for the hub can not physically be tilted that much. However, I am sure that the Class VIII will persist until proven that it does not happen on the single squeeze hubbing system.

BJ Neff

[notabot]

I now post.

[Dick]

BJ, I agree with the general quorum. I noted that the mis-slignmient was only a possibility, IE "It will also avoid the possibility of hub-doubling errors caused by misalignment of the second squeeze". If you will notice, the MINT does not say that it will stop doubled dies from occurring. I still like the tilted planchet as the MAJOR cause of the majority of the "central area boubling". From my experience with machinery, if a piece of equipment is properly assembled, then it will function, as desired. However, if something is not properly aligned, lightened amnd/or cojoined with other parts, it becomes a very "sloppy bit of work, by the mechanic/operator, and will produce the quality of specimens, as was the quality of work by the assembler. Normal wear, and tear, not withstanding. Dick

[eagames]

[notabot]

Thank you everyone for weighing in on this question.

[GarryN]

I wish we could come up with a different term for the "single squeeze doubled die." It just seems to be counter intuitive to use the term "doubled die". It is definitely caused by a different process, so the result should be described differently. Let's have a contest.

[Bob P]

Something people seem to be missing here is that the PROCESS is called the single squeeze. Whether or not each and every die is made by a single hubbing (or squeeze) has been shown to be not quite true. We can tell from the varieties that are out there as mentioned above, that there are extenuating circumstances. As those of you who work with machinery know, there are many times when the machine does not work as advertised. Alignment issues, and pressures used for the hubbings are not always the same. We can guess what caused all of these doubled dies, but we can not dismiss the fact that something happened causing the doubling on the die. For this fact alone, doubled die is appropriate.
Coppercoins uses the class 9 rating on these coins, except where the characteristics of the doubling conform to a well known class...such as the class 4 (offset hub doubling) coins.
For many collectors, knowing the class and how the varieties occur is secondary, or non existent to actually finding one. Like many of my young numismatics who I teach here...they could care less on how it was made. They just get real excited when they find something....anything that can be positively identified as a doubled die.

[notabot]

The semantic problem which arises is in using STRUCK, after Doubled, because there can't be any wiggle room when you use the word.

[wavysteps2003]

Lets face it, the single squeeze hubbing process has little information available on exactly what is happening. The MINT is being a bit stingy with releasing that information, although I have opened a line of communications with them on my on going, never ending, still in progress wavy steps/trails theory.

We know that a single squeeze doubled die is not made the same way as the multiple hubbed doubled die. I have mentioned this before and yet, we still use the same definitions for the single squeeze doubled die as the multiple hubbed doubled die.

As Bob pointed out, when most people find a doubled die in their change or when searching circulated or uncirculated rolls, they are not going to try and figure out exactly what class doubled die it is. To just about all, the class of doubled die and the definitions assigned are a mystery and left to the experts to figure out. However, this does not mean that those applied definition should be wrong and they are wrong when applied to the single squeezed hubbed die. They just do not fit correctly; the affect may be the same, but the cause is not.

There is much that we must learn about this system (single squeeze) in order to understand what is happening and in the 10 years (21 years if you count the experimental stages of this process) that have passed since its overall usage, we have learned little.

In the last 4 years, I have immersed myself into finding out what causes trails and wavy steps and why these anomalies are inherent to the single squeeze process. In the last year, I have learned more than the average bear concerning metallurgy, especially carbom base steels (I did have some understanding of this steel [HY-80] from being on submarines) and this knowledge has help me greatly in understanding what is going on and the differences in the single squeeze to multiple hubbing processes.

Yes, I have (at least in my mind) a theory in place just how trails and wavy steps are formed. Hopefully, it will be published at the end of the year. It will open a few eyes to just how different these hubbing systems (single squeeze and mutiplr hubbing) are for it introduces a NEW type die variety called design extension. Just how well this will be excepted is up to the numismatic community, however, I have been accused of trying to re-invent the doubled die by one expert already.

The point in bring up this theory on wavy steps and trails to to show that there is something new out there and it is coming from a process that we have little information on. And yet, there are some who are content rely on old definitions, to classify it as something it is not and hope that the majority does not ask questions as to why it is so named.

I can not help but feel that we are headed down the wrong path when it comes to the single squeeze hubbing system. We are using multiple hubbing, antiquated information and applying it to the single squeeze system and saying, "Yup, this is how it works". How will this reflect on us in the future when the truth is known if we do not correct these misconceptions now?

Enough for this post, boy can I ramble on . But really, think of what I have said; it is up to you the collector to make things right for this great hobby of ours.

BJ Neff

PS - I did forget to mention one thing. When working with hubbbing of the dies, the word "strike", "struck" or any related word is not used. A double struck coin is so very different in nature than a doubled die. The word "strike" or "struck" is strictly to define what happens to a blank planchet, which when struck, becomes a coin.

[Bob P]

Notabot,
I do not know where the word 'Struck' applies here. We are talking about hubbing. No where in the process is the die double struck.
I think we are to a point where we probably have as much info in this thread as we know. I would hate to continue trying to second guess things when the chances of learning something new and substantial is low.
As BJ mentioned, the mint is less than forthcoming on what I consider important information. Without that information, it's like beating a dead horse.
Maybe some future new information can answer your question better than we have here, but as I stated previously, most folks are happy finding doubled dies, and not knowing exactly how it occurred doesn't hurt a bit.

[daggit]

OMG I am so out of my league here