Double Die single squeeze hub??

[spatat]

Over the last several days I have been doing some browsing and re-educating myself on varieties/errors. Much to my surprise I have discovered DD are still being produced!! I thought with the move to single squeeze hubs and mint marks put on master dies all these type varieties would disappear. So this means I can search new rolls picked up from the bank?? Can someone suggest where I can get book/article on what to look for? One picture I saw shows distorted date with thickened areas on date. Little to no notching separation. I have ordered a scope from Ray and need to put it to work. Steve

[mustbebob]

Welcome to the forum. You are correct in that you can still find doubled dies, even after the advent of the single squeeze hubbing method. as far as what to look for, take a look through Variety Vista, coppercoins.com, or the wexler files to see what you have been missing. This forum has all the info you would need, so take a little time to look around. The links for the sites I mentioned are below. Welcome again!

http://www.varietyvista.com/index.htm

http://coppercoins.com/

http://www.doubleddie.com/

[VAB2013]

Congrats on ordering your Ray System! You are going to love it! You probably know a lot more about cameras than I did starting out, but there are some great threads where Ray was helping me (a total newbie!) so if you need help with anything, please let me know and I should be able to direct you to Ray's "fixes" on things. Ray's photography knowledge and how he applies it to coin photography is phenomenal! When I find myself getting off track and getting bad results - I keep going back to Ray's informative detailed descriptions and have written down many notes to keep me focused in the right direction!

[spatat]

Thanks for the links. I will enjoy a lot. I was able to pick up a box of 2019 1 cent rolls Very new looking at my bank this AM. Should be fun looking thru them. Take care hope to type with you some more.

[spatat]

Thank you very much. This time I ordered his microscope set up. Camera next. Maybe a little while. I want to go slow. Thanks for the tip. I will be looking for help when I get there. Steve

[jfines69]

Copper Coins (CC) has 7 2019 DDOs listed... Here is some info on single squeeze and here is some listings of DDs on Variety Vista (VV)... Hope that all helps a bit!!!

[VAB2013]

Thank you very much. This time I ordered his microscope set up. Camera next. Maybe a little while. I want to go slow. Thanks for the tip. I will be looking for help when I get there. Steve

That is so cool Steve, I didn't realize Ray had a microscope set up, but then I went to his website and saw that he has a pic of it, but not an information page. I'm really looking forward to seeing you working with this new set up!

[spatat]

Can someone explain how a single squeeze causes a DD? So far it seems that the DD is caused as the hammer die (Master or Working) die applies pressure to the planchet or working die one or the other slightly shifts causing the error. I assume this is a hydraulic press. If so would the pressure start low and increase? I could see how that could be used on the die. The planchet would not need the increase in pressure. The hammer would have enough pressure. Of course either could shift if the dies weren’t torqued correctly or if the collar was loose. Thanks. Steve

[VAB2013]

Steve, here's a little information to get you started until the guys show up. http://www.error-ref.com/?s=single+squeeze

and this from our Glossary

Single Squeeze: Single-squeeze hubbings began experimentally in the 1980s and became the exclusive method for hubbing dies by 1996. Before that, dies had to be hubbed multiple times to get an acceptable image on them for striking coins. By hubbing a die in a single attempt, the mint hoped to eliminate doubled dies from happening. However, this method ended up creating a new class of doubled die called shifted hub doubling, or Class 9 Doubled Dies.

Shifted Hub Doubling: Also called a class 9 doubled die, this is strictly isolated to the single squeeze era. It is surmised that as the pressure increases during a single-squeeze hubbing, that die can slightly shift into its final position, leaving some doubling. Since blank dies are convex, class 9 doubling usually manifests on the central design elements, especially the 6th and 7th columns on the reverse of Lincoln memorial cents, and on the left hand of Lincoln on the Formative Years in Indiana reverse.

[GrumpyEd]

Can someone explain how a single squeeze causes a DD? So far it seems that the DD is caused as the hammer die (Master or Working) die applies pressure to the planchet or working die one or the other slightly shifts causing the error. I assume this is a hydraulic press. If so would the pressure start low and increase? I could see how that could be used on the die. The planchet would not need the increase in pressure. The hammer would have enough pressure. Of course either could shift if the dies weren’t torqued correctly or if the collar was loose. Thanks. Steve

You are confusing the main point.

What you described is making/striking coins out of planchets.
Doubled dies have nothing to do with how/when the coins are made.
That is why we call doubled dies "doubled dies" not doubled coins.

Anything that makes doubling when the coins are made/struck on planchets would be strike doubling.

The whole definition of a "doubled die" is that the die itself is doubled when the die is made. The die is then used to make thousands and thousands of coins so a doubled die will make duplicate doubled coins as long as it is used, there is no double striking when the coins are made. That is why doubled dies are a variety not an error, everything went fine when it was struck (no strike error) but since the die was already doubled, the coin is doubled and we call it a die variety (because every coin made by that die has the same issue).

I hope that makes sense, the thing here is that doubled dies make real doubled die (die variety) coins, regular dies that bounce make strike doubled (minor error) coins. In what you said, you are talking about things that happen when normal dies strike a planchet. But you are talking about how a coin die (not a coin) can become doubled when the die is made with single squeeze. Single squeeze is the die making method not the coin making/striking method.

[spatat]

Thank you very much. The article has a lot of information. I read it quickly it will be interesting to read slowly tonight. Steve

[spatat]

So you are correct. I am getting ahead of myself. Back to single squeeze hubs. It sounds to me like the doubling could occur on single squeeze hubs when the master hub is creating the working hub where the pressure causes one or the other to shift. The cause could be the tech didn’t torque everything down or maybe the machine is two stages. If so the initial pressure brings the hub into position, starts the process and then applies the pressure required to complete the die. If that is how the system works that would explain one of the shifts. It is hard to think the hub could be put into place and full pressure applied from the start. It is interesting.

Thanks for for the response. Steve

[jfines69]

Normally the doubling occurs when the working hub is making the working die... There are some instances when the master die was doubled such as in 1972... Half of all the 1972 coins produced have the Master Doubled Die on the Obv (MDDO)... Here is Jasons tutorial on the 1972 ... As for DDs in the single squeeze era the working hub or working die jumping and making the DD is one theory on why it occurs... Another theory is the squeeze stopping them restarting making the DD... I do not think there is a definitive answer to the question as of yet??? Hope that helps a bit!!!

[mustbebob]

Jim made mention of a very important part of single squeeze doubled dies. Many times, the technician started the hubbing process and for some reason or another stopped and then restarted the procedure. Upon activation of the machinery the second time, the already hubbed portion of the die is then rehubbed a second time (a doubled die) if all of the settings and positioning were not perfect. This seems to be how the majority of the more major single squeeze doubled dies are made. The Mint has admitted on occasion that this was an issue they had hoped to curtail, so it is not a theory. Obviously, it still happens. Some years have hundreds of minor doubled dies, especially statehood (Minnesota) and America the Beautiful (Homestead) quarters.

[jfines69]

Thank you Bob for chiming in on my post... I'm glad we have the pros like you here to put us back on track!!!