Era related changes to Freight cars

Ever get frustrated by seeing people run double stack cars with cab forward motive power or wood sheathed cars being pulled by Dash 9s?  If so then this might be just for you.

At a recent NMRA regional convention in Rohnert Park, Bob Chaparro gave a great talk on establishing an era for yr railroad. It had a lot of detail on freight car changes through the 1900s in order to keep you honest in making sure the correct era cars were run.  I thought it would be cool to transfer this info into a look up guide in diagram form.  The era freight timeline pdf can be seen below….

Freight Car Timelines