Question About 10c Monroe

These are the 2 from Siegel


Perf 10 top


Perf 10 bottom

Edit: The census for this issue is 3 mint singles (one without gum), 12 used singles and 2 pairs.
The pictture below is a transition perf. 554d on the bottom. The right 3 perforations are perf 11 and the remainder are perf 10.

Russ,

How does a "transition perf" come about? I thought all U.S. stamps were rotary perforated using perforating wheels (or cylinders) of equally spaced pins and counterpart wheels (cylinders) of matching holes.

Steve

Steve,
The machine was somehow timed by the pins to provide the spacing. The following explanation is from Siegel Auctions, "The Perf 10 variety occurs only on a few stamps in a sheet affected by the error. During maintenance and repair of the perforating machine, some of the pins of one perforating wheel slipped into 10 gauge rather than the normal 11 gauge."
Edit: Below is a picture of the perforation room at BEP showing part of the 20 rotary perforators (about 1919).


The drawing below shows the pin wheel design. The part located in the center above the main shaft is referred to as the synchronizer.

The EDU of any of the part perf 10 flat plate errors is a 554d with a Gregory, Mich. Sep (27)?, 1923 postmark. It is known that all errors were from one perforator.
Census (1922 series)
554d 20 used singles, 1 used block of 4 with 2 error copies, 1 mint plate block of 6 (14411 UR pos 12, 13, 14)with 3 error copies, 1 mint pair with 1 error, 1 mint single, 4 covers (total 26 used, 5 mint)
556b 2 mint singles, 3 used singles, 1 used strip of 4 with 2 error copies (total 2 mint, 5 used)
557c 10 used singles, 1 used block of 6 with 4 error copies (total 14 used)
562c 3 mint singles (one without gum), 12 used singles, 2 used pairs (total 3 mint, 14 used)
568c 4 used singles, 1 mint single, 1 mint block of 8 with 4 error copies (total 4 used, 5 mint)

So here, I think is the same stamp, but... are they coils?
The two above are hinged but w/ original gum. Bottom two are canceled. I still can't count perfs right. The reason I ask is the next in the series are perf'd horizontally, and I haven't gotten into this enough to know one from the other. How do you learn to tell the years apart when they are issued over longer periods of time.

The coils are rotary press perf 10 vertical. The issue with the part perf 10 are flat plate perf 11 that were perforated perf 10 on one side due to a maintenance mistake made on the perforator. 12 stamps per sheet were affected with a perf 11, 11, 11, 10 perf pattern. Only a total of 78 copies in 5 denominations have been documented.
Edit: this series of stamps (4th Bureau issues of 1922) were issued in several formats:
perf 11x11 flat plate 1/2cent to $5.00 scott 551-573
imperf flat plate 1, 1-1/2, 2 cent scott 575-577
perf 11x10 rotary press coil waste 1 and 2 cent scott 578-579
perf 10x10 rotary press 1-10cent scott 581-591
perf 11x11 rotary press coil waste 1 & 2cent scott 594-595
perf 11x11 rotary press sheet waste 1cent scott 596
perf 10 rotary press vertical coil 1-10cent scott 597-603
perf 10 rotary press horizontal coil 1, 1-1/2, 2 cent scott 604-606
pert 11x11 flat plate 13 & 17 cent scott 622-623
imperf rotary press 1-1/2cent scott 631
perf 11x10-1/2 rotary press 1/2-10cent scott 632-642
perf 11x10-1/2 rotary press 11-15cent scott 692-696
perf 10-1/2x11 rotary press 17-50cent scott 697-701
lot of change in this series

Thanks Russ, So what you're saying is that all these are coils?



and they are flat plat printing, the plate sometimes slips and causes the odd perf counts. That makes it more visual. Still hard to know how you keep track of it all.

The coils you are showing are all rotary press (Stickney press) 5 cent (V) is scott 602, 10 cent (V) is scott 603, 1 cent (H) is scott 604, 1-1/2 cent (H) is scott 605 and 2 cent (H) is 606. The part perf 10 issues discussed above were cause by improper maintenance of the perforator after the stamps had been printed.

I want to re-emphasize this:




The perforation is done separately from the actual printing and is completely different process.

Printing, gumming, perforating, cutting, packaging...