Heisler Steam Locomotive

This is a roughly 1:38 scale model of a 3-truck Heisler steam locomotive, primarily inspired by the 90-ton "West Coast Special" locomotives, which were the biggest of their type ever built. The Heisler was the last of three major types of geared steam locomotives built in the United States, identified by its high tapered boiler, V-shaped cylinder configuration, and coupling rods on the driving wheels. Geared locomotives were often used on logging or forestry railroads, but the Heisler also made its way into mining, construction, and factory industries.

There are a few major reasons behind the design choices of this build:

1. The Series 5 Palette includes part 85489b, the flanged driving wheel, but excludes part 85489a, the blind or flangeless driving wheel. I took that as an interesting challenge for a big steam locomotive project. Since the Heisler has several 4-wheeled power trucks instead of a long, rigid wheelbase, it does not need any blind drivers, so it can be built just fine with the given parts selection. I've been meaning to make a Heisler locomotive anyway. Geared steam locomotives are quite fascinating machines.
   
2. I also added interchangeable coupler parts to make the locomotive more versatile. It can pull trains with either standard buffer magnets or custom-built couplers and older magnets.
   
3. I decided to make only a locomotive instead of a full train or a locomotive on a display track. This ensures all the parts and effort go into creating the locomotive without sacrificing detail or functionality for other side-builds.

A lot of TECHNIC construction was necessary to create the frames, trucks, and the drive shaft mechanism. The most difficult challenge was getting the the angled, telescoping drive shafts and the gears on the first and second trucks to function while still being able to run on sharp curves.

Stats:

• 1481 parts (1501 if counting Released Parts)
  
• Lengths:
  • Engine: 40.8 studs
  • Tender: 23 studs
  • Total: 63.1 studs
    
• Width: Mostly 10 studs, 11.8 studs at the cylinders and handlebars.
• Height: 16.1 studs overall, 15.4 studs from the top of the rail to top of the chimney
  
• R40 track compatible
  
• Power:
  • Powered-Up components are not included in the set, but the locomotive can be upgraded to run on a Large Motor and a Hub.