I noticed some really cool doubling on a 1942S in my collection. I'm pretty sure it's just mechanical doubling and not a doubled die, but boy is it dramatic. I've attached some close-ups of the date and the B in liberty. Wexler doesn't show this as a DDO, and it appears fairly shelf-like, so again probably just machine doubling. But it's still pretty interesting I think. Let me know what you think.
I agree, it does look like MD. I'd keep it around just to compare with any other doubling you come across.
Let's see the other side of that one, she's a beauty! That's strike-doubling on her. Think of what a doubled die is. It's a pair of intact impressions, just set off from each other. Do you see how these impressions are different? Some are flat, others are distended, distorted? That's due to a shaky strike.
@MercuryBen Most of it looks like die deterioration doubling to me (note the parallel striations) but the notch on the base of the "L" looks interesting. Can you post a close-up of it? ~ Chris
That diagram is misleading. The likeness representing "machine doubling" shows a curve between the upper and lower faces. To a draftsperson, this indicates a rounded surface, but machine doubling is supposed to be flat and shelf-like. That means the surfaces should be perpendicular to one another. People keep using this image to explain machine doubling, and I keep refuting the accuracy of it. I made a hobby of mechanical and architectural drawing, including CADD, for 50 years so I should know a little about the elements of design. ~ Chris
DDD. The shelf-ish directions are many and not isolated at the periphery (also on motto). The several directions of shift suggests deterioration. The 2/date looks like half is missing, instead of being shifted westerly...imo...Spark
