So am I correct that there is scale, semi scale, and O27 scale (from largest to smallest). Is scale = 1:48 across mfrs.
Lionel semi scale Are a smaller then MTH railking.
O27 is about the same across Lionel, William, K-Line.
Mth Rugged Rails= Lionel
for this discussion, plastic vs die cast trucks doesn’t matter unless one effects how high the car sits on the tracks.
Thanks for all the great information. Please correct any of my statements above.
Mark
Here are my guidelines for the semi-scale crap shoot:
Engines - Most semi-scale engines are similar. Some seem a bit too big like GPs, F-series, and more modern diesels. Watch out, though, for Lionel's Junior series (junior Berkshires and Hudsons). They are very compressed and matching rolling stock becomes a bit more limiting. Engine for engine, MTH Rail Kings appear to be a bit larger and more detailed than Lionel, Williams/WBB, or K-Line in the semi-scale arena but generally interchangeable.
Freight - Lionel traditional, K-line (not scale), MTH Rugged Rails, and Industrial Rail are all comparable and indistinguishable size-wise. I run many trains with a mix of all 4 brands. Williams/WBB's box cars are slightly bigger but work well. Some differences are realistic. MTH Rail King can work but many are scale or near-scale size. For that reason, I've avoided Rail King freight except for two 6-packs that run together. They are high-quality. The cabooses are ridiculously large, as big as other brands' semi-scale box cars.
Passenger - Lionel and Williams/WBB have a line of O27 streamliners that are the smallest and interchangeable. I think K-Line's are comparable though I've never seen one in person. Lionel also produced a line of slightly larger O27 streamliners (I have in ATSF and NYC) that are interchangeable with MTH Rail Kings. MTH's Rail King O27 Madison passenger cars are bigger than Lionel's but are really nice. I have two sets. They just can't be run with a Lionel Junior Berk or Junior Hudson but work with most other semi-scale steamers and also my semi-scale GG1.
Summary - most semi-scale items go fine together, you just have to be careful with MTH Rail King.