The Sea Train is a masterpiece of engineering that only a true master shipwright could build. According to Nami, something so big and heavy shouldn't even be able to float.
By design, a sea train is roughly immune to changes in weather. The train's momentum and speed allow it to pulse forward in any situation, even against an Aqua Laguna (a large storm that hits Water 7 once a year). Though it is still preferable to avoid traveling in such extreme conditions.
The tracks of a sea train lie just under the surface of the ocean, and sway with the tides to avoid any damage caused by the waves. The tracks require only occasional maintenance, as they are only used to boost the torque of the sea train's paddles on the ocean's surface, as well as a guide to its destination without the need for a Log Pose.
Whenever the train passes over the track, a device near the wheels makes an underwater dissonance that drives away Sea Kings.
Sea Trains[]
There are currently three sea trains in existence:
Rocketman was the first prototype sea train Tom built; it cannot be controlled and is basically a runaway train. Due to high safety risks, it could not be used commercially.
Puffing Tom was the second sea train made and first to be used commercially.
During the events that transpired in the Enies Lobby Arc, the Rocketman was lost, and the Puffing Tom was heavily damaged.
The Rocketman.
The Puffing Tom.
The Puffing Ice.
Non-Canon Sea Trains[]
Secon Island station.
Sea Trains were used as transportation by the people living in a small archipelago where the Straw Hats landed. Several sea train lines connect Dock Island and Secon Island as well as other surrounding islands. The rail system was far more elaborate than the one used by Water 7, employing signals and junctions for easier travel. The trains themselves were also more modern and refined, their design drawing inspiration from the 3700 "City" Class engines used by the Great Western Railway.[1]
Stations[]
The sea trains run through several stations, the first station they run through is Shift Station, which is operated by the conductor Kokoro who also lives there. The other stations are located at Water 7, Pucci, St. Poplar, San Faldo and Enies Lobby. Three of these stations are mentioned by name.
Blue Station: The station at Water 7 station which is operated by at least two people.
Shift Station: A station that lies somewhat away from Water 7 and also serves as a lighthouse for oncoming ships. It is the home of Kokoro, Chimney and Gonbe.
Day Station: This station is located at Enies Lobby, and it is the final station the sea trains can go to.
Around 24 years ago, Tom was considering building a proper sea train when he was approached by representatives of the World Government, who sought to arrest the fish-man for the felony of constructing Gol D. Roger's pirate ship, the Oro Jackson. At the time, Water 7's remoteness and proximity to a large number of Sea King, coupled with increased pirate activity during the early stages of the Great Pirate Era, made the port city undesirable for trade, slowly eroding the city and all who lived there. By building his "steam paddle boat", Tom would effectively save Water 7 by opening it up for trade, as well as save his own life. The judge overseeing Tom's trial agreed to postpone Tom's sentencing for ten years; if he was successful at building the sea train network, he would be pardoned for his original crime.[2]
When Tom began construction on Water 7's sea train network, he had already built a prototype of a steam engine that he called Rocketman. After drawing up a new blueprint. Tom's polished train, the Puffing Tom, was originally only connected to Enies Lobby, but Tom took an additional four years to build tracks to three other nearby islands: St. Poplar, Pucci, and San Faldo.[3]
The sea train is also responsible for Franky becoming a cyborg. When Spandam boarded Tom onto the sea train, Franky (then Cutty Flam) became enraged and tried to stop it. He did a full-on tackle to try to stop the train. When it ran him over, Franky's injuries were so severe that he had to replace his broken and damaged body parts with steel scrap.[4]
In the One Piece Film: Z, several sea trains appears to connect Dock Island and Secon Island. Those are the first sea trains in the New World and the only one so far to be non-canon.
The engine on the train is an American 4-4-0 engine or an American type steam locomotive. These types engines have eight wheels (four leading wheels, four driving, and no trailing wheels) and were used most common on American railroads during the 1800's and 1830's until 1928 and were given the name "American" in 1872 to show how they did all the work on every railroad in the United States.
