Since the last update, I've revised various elements on the 1st class car, and built the 2nd class car using those revisions.
The biggest change had me puzzled for some time. I have seen many papercraft train models with the windows shown as grayscale gradients, but a small minority of models had black windows. I struggled if I should recolor the windows to black from the prototype model--I did like the gradients. I went back and forth, and eventually decided to do a compromise which I think worked out. I redid the windows with a very dark gradient, which looked almost black. In hindsight, I think the original lighter gradient made the windows look almost metallic. But now, they're not as distracting. What do you think looks more "realistic?"
I adjusted the panel seams to make them darker, then tried and abandoned various experiments to make the internal structure resist warping. By reading various forum discussions, I think for some people that not having car numbers and information on the sides is considered an insult. Or worse. Not to worry, although it's hard to read, I added the car numbers and information below the bottom windows.
I also researched the colors for better accuracy, and became familiar with the wonderful world of Pantone color in the process. The red and blue should now be spot on, using Pantone Red 032 C and Pantone Reflex Blue C, but I still haven't discovered the correct yellow yet--I decided to go with Pantone 102 C, although it wouldn't surprise me if it's actually Pantone Yellow 012 C. It seems the SBB yellow is ever so slightly orange rather than a pure bold yellow... visions of holding the yellow section of a Pantone color guide against the 1st class car at the station, and getting really strange looks from people. ;-) For those who want to get technical about it, all these color references are for the older Pantone colors, not the newer Pantone+ colors.
OK, enough with all that. Here's the revised 1st class car.
Here's the 2nd class car.
One more topic before closing, and that's on getting the mirror symmetry correct on the cars' sides. Researching various elements on the "left" and "right" sides of the cars from photos, plus seeing differences due to upgrades made over time... can bring out lots of inconsistencies and drive one bonkers. Four windows? Five windows? A vent with a cover? A vent without a cover? No vent at all? Aaaaaaaaahh!
From all the reference images I've seen, it appears the 1st and 2nd class cars differ in where the same element appears on the "left" and "right" sides. Have a look at this:
The caution strobe location atop each rail car is marked with a green triangle, and its position is reflected nicely on the opposite side. For reference purposes, this strobe can be thought of as marking the "front" of each rail car. Although in reality, it could be the back--who knows really?
The first class car, mostly, does not have the same feature reflected in the same position on the opposite side. The green circles mark diferences in mirror symmetry. On the other hand, the second class car does show mirror symmetry with the same feature reflected in the same position on the opposite side.
For both cars, the SBB logo and panel seams don't have mirror symmetry.
In trying make sense of what has mirror symmetry and what doesn't, you get the feeling that the rail cars were designed so they could be attached "backwards" and still look visually consistant with the other cars. On the whole.
I think that's enough for now, so I'll end with a clue about the next rail car to be built.
It goes a long way when it's both on the top and bottom, doesn't go as far when it's only on the bottom, and sometimes isn't included at all.
Cheers!