I have a question about Machine Doubling. When coins are considered machine doubled, is that a problem with the minting press that contines to happen until fixed??? Like what causes it and how is it different from a Double Die. I ask this because I am working on 10 Roll sets of memorials and have been trying to pull what ever high grade coins that I can out of change. Anyhow, in one coffee can, I found about 15, 1989 Ps with a very clear doubled date. I could easily see it with the naked eye and it really stands out. Im calling it machine doubling, only because of how many I found and Ive never heard of a 1989 double die. Also, are machine doubled coins worth anything in BU????
Machine Doubling/Mechanical Doubling results because of loose parts in the coining press. Once the loose parts are tighten the doubling stops. There's also Die Deterioration Doubling and Abrasion Doubling. These types of doubling are not that popular to collect. Lou
Also, quite a bit of the Machine Doubling for the past several years, is a result of what is referred to as chatter! This occurs when the Hydraulic Presses sort of burps when the Dies Strike the Planchet resulting in a Double Strike that usually pinches off a small amount of the previous Strike. While many experts and Mint workers can't explain what causes this, anyone that has worked with hydraulics, has seen machinery act pretty much in the same way. In a lot of cases, this is caused by air bubbles within the hydraulic system of the machinery. Frank
There are several good articles on the differences. Google. Here is one http://www.geocities.com/NCADD/educational1.html
CONECA has 6 listings for the 1989 doubled die cent, five obverse and one reverse. http://www.conecaonline.org/content/lincolndoubleddies19801997.html#_1989 Larry Nienaber
Wow, this is some good stuff, thanks. Im on my way out the door, I have to work out of state for about 3 weeks. So, Im only taking a quick look now, but but when I get back, Ill see what I can do about trying to get a clear picture. Thanks for all the info, but I wont be back for a few weeks, see everyone then.
By the way, there are more than 29 doubled die varieties listed for 1989 Cents. many effect the date and the TRUST of the motto. Is there any chance of posting a picture of the date on one of these 1989 cents? Thanks, Bill
