Flat Print Vs Rotary Print With The Medallion Issue

... and again for historical perspective this seems like a great spot to drop this info from the US National Postal Museum:

The first U.S. Stickney rotary press stamp was a coil issued in 1914 as Scott # 459 which was imperforate. The first perforated rotary press coil was also from 1914 as Scott # 453 perforated 10 (Kiusalas 10-80) vertically and Scott # 449 rotary press from 1915 first perforated 10 horizontally. The first U.S. rotary press sheet stamp was issued in 1920 as Scott # 542 perforated 10 (Kiusalas 10-80) by 11 (Kiusalas 11-72.5 currently corrected from Kiusalas 11-73 which is incorrect and non-existent). Rotary press issues Scott # 543 as well as # 581 to # 591 and # 612 were perforated 10 (Kiusalas 10-80) by 10 (Kiusalas 10-80). However, careful measurement will reveal a slight difference in horizontal measurement (9.85) versus vertical measurement (9.875) for these. The first rotary press booklet stamp was issued in 1926 as Scott # 583a perforated 10 by 10 as well. The new rotary press perforation 11 (Kiusalas 11-70) by 10.5 (Kiusalas 10.5-75) was first issued in 1926 as Scott # 634 (and 10.5 by 11 in 1931 as Scott # 697 and # 699).

This seems to contradict both jogil and Unitrade (Introduction, "Paper") regarding rotary and flat plate printings of both the Arch/Leaf and Medallion series. So does the the second paragraph of the "Method of Printing" text that Koala included.

Also, Unitrade seems to contradict jogil regarding design size of those same two series: "Rotary press copies are slightly taller than those printed by Flat press method" (ibid).

Please correct me if I've mistaken something here.

EMaxim: The above quote mostly applies to CBN printed stamps rather than BABN printed stamps.

After very careful measurements, it has been found that BABN dry printed flat plate press printed stamps are slightly wider horizontally and slightly shorter vertically than BABN wet printed rotary plate press stamps which are slightly narrower horizontally and slightly longer vertically than BABN dry printed flat plate press printed stamps.

Thanks for clearing that up. I'm still relatively new to Canadian stamps and was starting to feel confused. As for the size difference btw BABN dry flat plate and wet rotary stamps: I find something like 0.5mm, wch I'd agree is slight.

Hello,

the last years there have been some discoveries and I am not sure I saw all of them.

Is it still correct that for the Admiral stamps the difference in size is in the wet vs. dry printing because the stretch of the (smaller) rotary plates is not important enough to additionally look for the rotary vs. flat size difference? (only wet vs. dry in general there)

In the Medaillon issue we have the 1c 195d and 2c 196i being on both dry and wet rotary printing, not other new listings?

In the Arch/Leaf issue, I did not find any information about new discovered printings concerning the design size (only about the flat perforation 164, but here I ask about the printing/sizes)?

I also found this interesting summary by jogil, but some time ago, perhaps not complete:
https://goscf.com/t/58377#511412

And mainly: what are the size differences between the Stickney Dry vs. Stickney Wet printing vs. the Flat Dry Printing as a rule?

See the following article: http://philatelist.collectorsclub.o...05/34954.pdf

thank you, indeed my "mainly" question is explained there.
Also, there should be 3 Stickney dry printed Medallions stamps listed all in all in the future, 1c, 2c, 3c.

For Arch/Leaf: do in general the same size rule work as with the Medallions?
For Admirals: I saw an article heading for a newsletter about "Flat Versus Curved Plates in the Admiral Series" (which I don't have), was there any new information so that there are important size differences or is it still the case that for the Admirals the size difference is only by wet vs. dry?

Also see:
https://bnaps.org/hhl/TopicsDisplay.php?issue=1969
https://bnaps.org/hhl/TopicsDisplay.php?issue=1973

With regards to the Admirals, only some very early stamps were sheet-fed flat plate printed while most were sheet-fed rotary printed. However, they did not find any differences in their sizes based on flat versus rotary.

thank you - good to know with the Admirals. (interesting by the way that the design size was a little bit smaller than in Arch and Medallion, wasn't it?)

About the Arch sizes I read there:
"The design size of the Medallion sheet stamps dry printed on the flatbed press is, as
expected, the same as for the 1931 Arch sheet stamp counterparts."
and
"Medallion sheet stamps printed on the Stickney rotary press are comparable in size to the Arch sheet stamp rotaries."

I would answer my question about the size rule then with a "yes".

But as the deciding size difference in the width is really small, can you though use a template perhaps to look out for Stickney dry printing in the Medallion issue? Probably you will miss some then (or have to double check by perforation of course)

Technically, now some BABN Arch stamps that were thought of being sheet-fed flat plate press dry printed are now being considered as being sheet-fed rotary plate press dry printed due to horizontal hairlines (Scott # 168 pls.1 & 2, 169a pl. 3, 170 pl. 3, 172 pl.3)

Thank you again!