I came across this $1 note the other day. As you can see, the 7's in the serial number are different sizes. I thought at first the 7 was just shifted. After closer examination, I found that they are indeed different sizes. I also thought perhaps one digit got a bit more ink than the rest, or was smeared when printed. But then why would both sets of serial numbers on this bill have the same effect? I'm a bit puzzled. I actually measured the pixels in the photo, and the larger 7 turns out to be 6% bigger than the one next to it. Any thoughts as to how this happened?
I agree with the other opinions that you've just got a bit of overinking, and that it's pretty common. It's also fairly common for inking issues like this to affect both serial numbers identically. But I have no idea why. The two serial numbers are printed from different numbering heads, so I don't see why they should often show the same inking quirks. Does anyone have an explanation for this?
FWIW, since this has come up a couple times, I sent a note off to the moneyfactory, to ask them for some details. The response was: Now I just want to know even more Dave
Perhaps there is a master set of numbering heads, and copies are made from the master set, just like the engraving plates. I assume they wear out and are replaced after some use. So if there's a defect in the design of one digit, causing it to be under or over inked, then that effect is reproduced on all notes until its caught and new numbering heads are made.
Maybe each number head has its own ink cartridge/supply? Different numbers require different amounts of ink. The #8 would likely run out of ink first and the #1 last. To save money, each ink supply would likely be changed as it becomes empty or close to it. The #7 cartridge would have to be filled/changed just a touch more often than #1. ???
Wild. Especially the $20 Note. I need to start looking at my bills a little closer. Maybe the issue is with the rollers, but that would not explain the double 7s. Maybe the Treasury is counterfeiting their own notes?:dead-horse: