Lincoln's Broken Nose

[murphy]

Generally I don't give a die crack much attention at all, but so far, this year has produced way more crack head Lincolns than I'm use to seeing. And how many times do we see a crack going down the length of Lincoln's nose? This is the first that I've seen like this.
It's been suggested of the doubled dies that I found this year were coined on such worn out machinery that they probably never made it past the mid-die state and that fact would serve to reduce their populations quite a bit. I don't know but it's probably true. One thing I do know is that I've seen more severely cracked Lincolns in 2005 & 2006 than all the other years combined.

[Bob P]

The die cracks for 2006 have all been rather different. As far as die cracks on the nose, 2006P-1DO-006 shows onel, with a die chip as well. I am sure there will be more strange ones soming.

[wavysteps2003]

Yes, there are certainly more die cracks this year than any other year and they seem to forming in the earlier states of the die life.

The only way that we could faulty the machinery is if there is to much pressure being applied from the hub to the die which would make the die more brittle and thus subject to cracking, but that would relate back to the hub press operator. Another cause could be that the mint is using a source of steel that is not quite up to par or it could be a combination of both.

What ever the cause though, die life is shortened, more dies are used and thus the possiblity of varieties does increase. That makes me happy

You all have a good one
WAVYSTEPS2003

[eagames]

Yep, almost every 06P variety has some cracks.

I just found a 1D0-006 and it does not have the big nose bump that most have, no sign of it but it has all the other markers. I would call it the same die state but no bump.

That tells me that the nose bump appeared instantly.

Sort of changes my thought that bumps like that appear slowly. Another sign that these new die fail abnormaly.

[coop]

I find the opposite on the Denver ones made in 2005 & 2006. Most of the 2005-D had dies cracks on two to twelve columns. On the obverse some had die cracks on the nose and few with die cracks on the head. I had to search many 2005-D to find complete steps. I'm not talking about all 18 of them, just the upper ones full. It was hard from examples last year from this area to find enough to put away. I found better ones traveling out of town to obtain ones from circulated rolls. Most of the steps looked like the steps on 60 & 70's coins.
The 2006-D has very limited amount of cracks, usually on columns 1 & 2. Obverse very few cracks on the Denver ones. So I see a pattern going here. Something the Philly mint is doing/ or equipment failure/ proceedure not followed/poor materials used. But with the two mints making different quality coins, it could even be human error in how things are done at each mint?

[wavysteps2003]

Hi Coop - It is great having a searcher way out west who can give us a report on the Denver minted coinage. From your indicators, it looks like the problem is centered around the Philadelphia Mint since I believe that the die stock that is used, is used by both mints. That would lead me to believe that high pressure is the culprit then. For those of you that are not familar with what happens to metal under pressure, this is it: as high pressure is applied to metal, the molecular bond between the atoms begins to change to a crystilant structure making the metal much more rigid and also more brittle. This can be reversed by applying heat to the metal and cooling it slowly (fast cooling also has the same effect of changing the bond between atoms and making the metal more rigid). This annealing was used in the multiple hubbing method, where after each hubbing, the metal was softened so that it would except the next impression from the hub. So when we look at a to brittle die, it is either caused by over pressure to the die or improper cooling of the die.

Now for the steps. Aaargh, I am going to say it even though it may get me in trouble. Another form of wavy steps, one where you are not seeing fluting line extension, but step upon step extension. Remember that the steps are very close to the center of the die and any laterial movement between the hub to the die will be seen mostly in that area. Doubled die - yes; of any consequence and / or collectible - NO, NO, NO.

You all have a good one

WAVYSTEPS2003

[coop]

Having taken shop class in high school, in Metal shop one of the projects there were to make a screw driver. They had the plastic handle material and the octogonal Steel stock. They made the two into a screw driver. (Of course that was in the stone age...) But taking that class taught me a couple of things. One dealing with the handle and one dealing with metal. The Steel stock was cut to the desired length and then heated till the steel turned Red with a torch and then let cool slowly. This soften the steel to hammer on end of it to form the screwdriver tip. When that was the way and size we wanted it, the the steel was heated again to harden the steel. How was it tempered. If you haven't see this you may not under stand it. After heating the entire shaft to red hot you would brush the upper metal with sandpaper to see the hardening take place. The steel had a blue line flow to the tip and then it was dropped exactly when the blue reached the tip into cold water. The shaft then was retrieved and sanded and the handle was applied. But something of note. One of the kids didn't do the tempering step exactly correct and when returning with shaft to continue working on it, he dropped his and it shattered like an icecicle. Broke into several pieces because it was too britle. So if the tempering is off just a little it can be too hard, too soft or just right. But seeing the blue line run down that Steel is something you have to see to appreciate. The handle was attached by drilling a smaller hole and the shaft heated and then shoved on the handle. I didn't like that cause it turned the hand black and you couldn't see the shaft. So I mentioned that to the teacher and I made a suggestion. I heated the handle in very hot water and shoved the handle on while it was hot. This left no marks on the inside of the plastic, and when cooled the shaft was firmly in place. I got an A for the class and the teacher got a new way to teach his students on how to attach the handle from then on. I guess even back then I always found a better way to do things and I guess I'm still doing so today. Somehow the screwdriver got away from me after all these years, but the memory and lesson still exist and I share it with you now. (Sorry if this story bored you) But it true.

[murphy]

Far from boring Coop, nice story.

[bruce 1947]

HI MURPHY
Disregard my e-mail I finally was able to logon, some times I just can't get on.

[penny_wise]

Thanks for the screwdriver story. I have 28 years in metals. There are three ways to harden material. Chemistry, work harden, or heat treat. I will keep my discussion to steel and steel alloys, including tool steel. Of course there is a combination of the above. If too hard, steel will crack. If heated, then quenched in an inappropriate media, steel will crack. If there is a hairline crack, then heated and quenched, steel will crack. I am no expert on mill dies and thier processes; however, steel, being steel, will react as stated above.