ILLINI / COLUMBIA Variaions...
I know this topic has been covered before by myself and Mersenne6, but I have a couple of items to add to the discussion.
First some background on the Illini type cars. The Illini and Columbia coaches were introduced in the top of the line 20th Century set in 1922, with the new NYC type T locomotive. Early Illini coaches are dark green and the early Columbia coaches were brown. There was no true observation car in these early sets, just a coach with little porthole type markers on one end. In approximately 1925 American Flyer started making observation cars. Also, in or aound 1925 switched the colors of the cars, the Illini cars became a lighter green and the Columbia coaches became more of a maroon color. For whatever reasons, the Columbia cars were discontinued in or around 1925/26. All I really can say about this is that there are few maroon sets.
American Flyer kept the Illini cars in their top of the line O gauge sets through 1927. In 1928 the top of the line O gauge sets become enamel painted cars and the Illini cars are not shown in the catalogs after 1927. Although not shown in the catalogs, the Illini cars did not completely disappear until approximately 1932??? The later production of these cars appears to be limited to lower priced offerings by various department stores / wholesalers. JC Penney used these bodies in one of their store branded Nation Wide Lines trains and Montgomery Ward showed the cars in sets in the 1929-1930 era catalogs. The later, uncataloged cars also kept up with Flyer's production as extremely late sets are found with gray trucks, instead of black trucks.
Getting back to the point of my post, I would like to show some pictures of sets that transitioned the 1925-1926 era.
First here are some pictures of a number of different variations of these sets.
The above picture shows a number of variations from the 1922 through approximately 1925 era.
The above picture shows sets from the 1927 through 1932 era. This photo shows some of the changes that occurred during the late production, such as the roof ventilators on the cars disappearing after approximately 1927-1928 and the trucks changing from black to gray paint.
During the 1925 to 1926 era, as production features changed on these cars, some variation crossovers appear. First off the below set features a Maroon 3020 engine, brown baggage, brown coach (with observation portholes), and maroon observation. This is a boxed set, with setbox and all boxes are correctly labeled for brown/maroon colors.
Brown Baggage with early style trucks
Brown Coach with later style trucks
Portholes on Brown Coach
Next up is a set c. 1925 that is believed to have been sold through Butler Brothers as a 7000 series uncataloged set that included accessories (station, tunnel, signals, and 2 trees) as shown in a c. 1925 Butler Brothers catalog. I believe this to be true as I acquired several boxes of track that was marked with Butler Brothers numbers and two trees from the seller, who purchased this set along with several accessories from the original owner's family.
This set features light green 3020, dark green baggage, light green coach, dark green observation, all with the harpoon couplers that were found only on Illini and Columbia cars. I have found that it is unusual to find the light green cars with harpoon couplers.
So the next set represents a bit of a hodge podge of stuff, as the cab on the 3020 is numbered 3019 and came in a box marked 3020, came with a brown baggage car and a light green coach, all with harpoon couplers.
Next up is one of those late oddities. As mentioned, American Flyer was making many changes to their line over the years. In addition to the colors of the cars changing, American Flyer changed the truck styles, changed the coupler styles, changed the door handle styles, changed from the roofs having ventilator bumps to being smooth roofs, and discontinued the use of air tanks on the cars.
So the following set is a boxed set dating to 1926. The set features a black 3014 engine, light green baggage, light green coach, and dark green observation, all cars having hook couplers and air tanks. It is very unusual to find air tanks on the cars with hook couplers, I know Mersenne6 has a set, but I do not recall the details of his set. It is also very unusual to find the dark green bodied cars with hook couplers.
The dark green observation car, shown above, appears to have had one side put in the press wrong, as the observation railing and body did not fit together well, when I got it. I had to take it apart and make a slight adjustment to the body so that they would fit together better. I discovered that the body has a very small rail that sits flat on the frame and that there was a small area that would normally sit flat on the frame, but due to the body being in the press wrong, there was a small flap of metal that would normally be flat along the frame, but was bent inward from the side and was mis-aligning with the observation railing and causing the whole end of the car not to fit well together. I adjusted it and the car fits together better.
The last unusual Illini series car I have is a car from c. 1932. This is the latest illini set that I can put a specific date to. I attribute it to 1932 simply because of the engine, which features a casting that was not introduced until 1932. This set came to me as a boxed set, with setbox and individual box for the engine. I believe the tender and cars were likely wrapped in wax paper.
The engine is most unusual, in that it features a bell, which is attached by a screw from the bottom (as these die cast engines typically had a cast bell that had a shaft protruding through the casting that was then peened/pressed to hold it in place) and the motor is an early style that was typically found in a cast iron cab.
There is also one other feature that makes this engine special, its original box, which is marked 3357 Loco, a number that has not been reported previously.
The tender with the engine is also the earlier style body that is punched for the standard gauge sized square plates, but is decaled instead.
So the transition part of the cars on this set, is found in the baggage car doors.
The doors are dark green with the early style cast door handles. Obviously someone found some old parts (doors) and put them on this car at the factory. I have also seen late light green cars with brown doors, which would be from a Columbia baggage car.
The coach has the rounded windows being un-punched. It is thought that these un-punched windows is a result of the production of the JC Penney Nation Wide Lines cars, which featured the same bodies, but a different lithograph and did not have these arched windows, and no need for there to be punched windows in this area.
Lastly, the observation car
Mersenne 6, please re-post the photos of your set with the hook couplers and air tanks. I would appreciate more information on that set.