1939P Trench

[lineop3]

I've never seen this trenching around the frame before. Did someone purposely do this?
1901519016

[jcuve]

There was some retooling of the Master Dies by the Mint designers. If you read Dr. Wiles study on Lincoln Cent obverse design changes you'll see at what point it happened and if he thought it was on the galvano or the Master Die. Check Variety Vista dot com...

[trails]

I disagree with the theory that this engraving was done to the master die or even the master hub. If that were the case, then ALL Lincoln cents from 1934 to 1943 (these are the dates that this technique was used) would have the channeling around Lincoln's bust and that is not so. However, look to the working hub as the device that was engraved (or channeled). Lastly, this could not have been accomplished on the working die for it would have been a build up of metal that was higher than the field; just no way that this could have been done.

I have heard a few different theories why this channeling was accomplished and the one that seems most reasonable was that it was accomplished to prolong die life. Seemingly it did not quite meet up to what the MINT had expected and this practice may have met the end in 1943 (this is the last date that I have seen channeled).

As far as I know, there has not been an in depth article on this subject and if I can gather enough material on the subject, I will try and write one for the various publication that I contribute to.

BJ Neff

[mustbebob]

I agree completely with BJ. The re-engraving was done on the hubs, not the Galvanos, or dies. This is the only way it could leave a recessed trench around the bust. This did prolong the life of the design.

[jcuve]

I guess that would make more sense being done on the MH, which may be what Wiles stated, not the MD or Galvano which I may have mistakenly typed in my quick reply this morning.

...I have just been too tired lately and need to think before I type. Obviously it couldn't possibly be done on a Master Die :squigglemouth:

POSTSCRIPT: Looking at Wiles document (LC Obverse Design Changes) he lists the trench starting in 1935 and was done on a MH (he has it labeled MH-15). Sorry for any confusion guys, I really need to not reply to threads at 6AM...

[trails]

I still disagree with the master hub theory. That would mean that all coins in that particular year would have channeling around the bust. This is definitely not true, only a certain amount have this feature. Dr. Wiles should re-evaluate that statement.

BJ Neff

[lineop3]

Such power hitters!
Thank you all. Would I find this info on a web site or from a particular book?
And under what reference/title should I look?

Aisha

[trails]

Chuck Daughtrey mentions this in his book "Looking Through Lincoln Cents", page 153. While he focuses on the 1943 Lincoln cent, he does mention that it happens "sporadically" in other years.

I independently notice this engraving when I was in the process of listing the hub changes for the Lincoln cent. However, like Chuck, I noticed that this was not occurring on all the coins within the same year during the time period mentioned. So, I did not mention this fact in my final "Master Hubs and Master Dies of the Lincoln Cent; 1909 to 2007", mostly because I thought it was due to an engraving of the working hub.

Looking through my 1943 Lincoln cents, I have found some with engraving and some without. I have included the pictures in this post of each situation. As I have mentioned before, I will do an article on this subject for it has piqued my interest.

BJ Neff

[lineop3]

Wow. That's a great example BJ. I would like to know more about it when you do find something more.
This is something we haven't seen here on site. Great research!

Aisha

[jcuve]

I can entertain this idea that Working Hubs were modified on occasion with a specific method (i.e., a channeling around the portrait). I am not sure I have enough BU wheats on hand to add any data to this argument at this time though.

If it was done on Working Hubs, was it only done in Philadelphia or also at the branch Mints?

Thinking further, can some produce photos of two coins that are EDS, same year, one with and on without the trench? And then maybe two EDS Lincolns with the trench, different years where there is a noticeable difference in some aspect of the trench?