How To ID W-F - No Straight Edges On Rotaries?

When I first joined SCF, I remember some kind person shared with me that the straight-edge Bureaus (with guideline ink) 17c / 20c / 25c etc. cannot be the p10 1/2 x 11 because of the way they were printed.

Is there some similar rule for the W-F rotaries?

I have a number of WFs with straight edges and ink showing, so it might help me narrow down the possibilities more speedily?

Any other such quick tricks (other than counting perfs of course )?

I'm looking at a giant pile of 1c with Louisville, KY, T205 precancels that I'd like to reduce to just the 2 or 3 I might actually need. Brunell says this type was issued on 1912, 1914, 1917, 1919 (=several different rotaries) and I am finding a lot of 10.5 perfs, which don't exist, so I need some cheats to get thru this.

Thanks.

Straight edges occur on every sheet of stamps as they are cut down from the original printing sheet. Most of the Washington / Franklins were printed from 400 or 200 Subject plates and then cut into panes of either 100 or 50.

Example:

http://www.1847usa.com/PlateLayouts...teLayout.htm

Check the cut lines as all stamps on the cut line will have a "Natural straight edge"

My vote: rotary press w/f's do not have natural straight edges [unless they are the error imperfs].

ps: if your w/f's are coming up 10 1/2 gauge, get a new gauge :)

pps: after you have looked at a few thousand of these, your eye will distinguish the p12, p10, and p11 without much difficulty. Sometimes p10 rotary's and flat's can be tricky to tell apart. P11 1918 offsets are usually easy to separate from the flats. The one you want to be SURE you have right is the p11 flat (SC498) versus p11 rotary (SC544/545).

I'm sorry, this stuff completely confuses me.

Meantime, I have perfed 46 stamps -- 44 are p10 (i.e. approx. 10.25/10.50 so I am rounding down because the p11 gauge fits the perfs worse than the p10). Two are p11 and flat printed.

So the 2 are #498.

The other 44, I have just finished measuring -- not one Rotary. Now I know chasa told me a while back that comparatively few Rotaries were precanceled, so that makes some sense.

However, I'm also wondering ---- just how clear is the distinction in size between Flat Plate and Rotary on a 1c W-F when you measure it? I checked my US album for a comparison and found I have zero Rotaries in there -- is that because the difference is too small for me to see, or is it just chance? I don't know, but it doesn't seem that I have had any luck finding one in the past year, which is suspicious (but not 100% impossible).

43 of the ones I measured today were consistently dead-on 18.5 x 22-even, to my eye.

The ONLY one that seems different measures more like 18 x 21.5 ... it is a much brighter green than the grayish cast of all the others and it has a SE with a visible guideline. What does this all mean? It doesn't seem to fit the size of either Flat Plate or Rotary, it is definitely not p11 and the foil test does show an oval on it.

Many thanks to anyone that can enlighten me on any of these issues.

chasa: Thanks. For Louisville, per Brunell, there are no p11 Rotaries in T-205. Yea! Therefore, I am comfortable in this instance that my p11s are in fact #498s. [They measure right, too, but as you can see my faith in my mm scale is not great.]

Funnily enough, the gauge I am using is brand new, out of the envelope this morning. The one I've had for about 35 years is wearing out on the numbers 9.5, 10, 10.25 and 10.5 (not the dots, just the numbers, but it still makes it harder to use), so I splurged.

[Pause while I compare the new/old gauges to see if there's any difference ... nope, the dots on both line up perfectly] I think I am just having trouble reading some of the ragged perfs.

So I think that leaves me with: are the rotary/flat size differences easy to spot and why is my bright green SE p10 measuring smaller than expected?

Counterintutively, the best way to measure size is not with a ruler.
Compare with a known flat plate stamp, here with a 9 canter.
The wide rotary's (SC545 & SC546) are more than a frameline wider.

Here comparing a tall P10 rotary SC543...

I know I'm changing the subject, but those Greenwich, Ohio precancels made me look up the history of that town (which I never recall hearing much about before) and came up with this summary, confirming that the town was named after Greenwich, Connecticut:

OK, so yes, the difference should be quite clear. I had vaguely read about doing this -- someone online suggests cutting the corners off a common stamp of each type to create a template ... which I'd never do, even if I had a rotary to go by ...

Could I use a Bureau rotary (for comparison, not cutting!)???

Here are scans of my brighter green 1c with a typical grayish green one behind. I'm not very expert at lining them up, but I think you can still see that the bright one is smaller in both dimensions - about 1/2 mm each way.

So what do you think is going on? Even if I am mis-measuring with my ruler, why is the bright green one smaller in both directions? And surely my (larger) gray-greens can't all be rotary?

Or maybe the variation by .5 mm is within the margin for both being flat press, but one is a 424 and one a 462?? (which?)

back is taller rotary SC543
front is flat - either SC424 or SC462

Wow. OK, thanks chasa. That means my stack of gray-greens are all 543s, then, because they all line up together. Maybe I *should* chop one of them up as a template for the future!