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Have you ever seen a true 1992 Plarail Thomas? Do you even know how you would check? Here's some info!
Here's three Thomases, one from 1992, one from 1994, and one from 1995. Ignoring condition, you can spot a Japanese made Thomas (92-4) externally in a few ways - the front axles are different, and the back couplings are an earlier design. They are also marked Japan underneath
Inside, the battery contacts will be brass instead of silver. The most telling thing though is the date code sticker, though. The digit is the last digit of the year, and the letter corresponds to the month - A=January, etc. This carries through to today!
Here's a few more recent ones. They are often molded into the plastic now. Tender engines have a sticker under the battery compartment, which is lost half the time, so it's harder to date them.
Tender engine axles have also been changed, made in Japan engines will have axles that were hammered flat after wheels were installed instead of the caps used now. Tender battery information also changed over time.
Annie and Clarabel were also updated, originally having the earlier coupling style and Japan markings, then Thailand markings but the same earlier under chassis style, then finally the updated chassis with different screw holding style and sharper Tomy logo
Tomy also used the same date sticker system on the TomyTrains engines too!
And believe it or not HiT engines are dateable down to the day! This Gordon was produced on the 209th day of 2008 in factory E, whatever factory that is...
Road vehicles are also marked, on some early ones there's even a separate chassis mark as seen here. (This Bertie was made in two different months!) You can see where the mold was altered to say Thailand, and that an additional screwed cover was added to the battery compartment.
