Aef Panes: What Is The Difference Between Positions W1 And W3

I have an AEF pane (Scott 498f), and I cannot determine whether it is a position W1 (or W7) on the one hand, or a position W3 (or W9) on the other hand. The literature I have found says the bottom margin on the W1 is wider than the top margin, and a W3 has approximately equal margins. In light of the fact the panes will always be 3 inches (76.2mm) tall, and the printed portion of the pane will be 71mm tall, that leaves only slightly more than 5mm of margin. If there is 3mm of margin at the bottom and 2mm at the top does that make it a position W3? Where is the cutoff?

Is it really just a judgment call, or is there a more precise way to make that determination?

Have you checked the booklet pane section of the Scott US Specialized Catalog?

Yep. Not helpful.

You might want to take a look at the article in Opinions II, Philatelic Expertizing--An Inside View, "Determining the Genuineness of United States "A.E.F." Booklet Panes" by Richard F. Larkin, pp99-113. (The Philatelic Foundation, 1984).

Other references for AEF pane ID:

1. Linn's Stamp News,July 17, 1995, pp10-11, " New Discovery on Sheet Format of AEF Panes", Ken Lawrence.

2. The United States Specialist, October 1996, pp421-422, "Expertizing AEF Booklet Stamps", Ken Lawrence.

3. Same, July 1996, pp296-298, "A Cautionary Tale", William H. Hatton.

4. Same, January 2011, pp18-21, "AEF Booklet Pane Position Distribution", R. Gordon Schmidt.

5. Same, June 1995, PP244-251, "The AEF Booklet Panes of 1917; What Positions Really Exist?", D. B. Littlefield and Wallace Cleland.

6. Same, January 1986, pp29-30, "Thoughts About the A.E.F. Panes", Richard Larkin.

7. The 1999 Comprehensive Catalogue of United States Stamp Booklets, Postage and Airmail, Robert Furman, pp60-63 (Krause Publications, 1999).