BR 62

Like the Prussian T-18, (later known as the BR 78 under the unified system), the Reichsbahn BR 62 “MAMOTH” was conceived and built as a 4-6-4T with an emphasis on economics and simplicity.  Many years before any European 4-6-4s existed, the American locomotive builder Norris had demonstrated the feasibility of high speed locomotives by utilizing a four wheel leading truck configuration which provided a safe and stable ride even on rough tracks.

Although the Norris configuration became very popular in North America, it was not used in Europe during the early days of railways owing to the relatively short runs and smooth tracks that existed there.  Also, European design philosophy required that the maximum possible adhesive weight be placed on driving wheels thus eliminating leading / trailing trucks.

However, in the later part of the 19^th century, European locomotives with leading / trailing trucks made their debut; this was the result of locomotive weights becoming too heavy for the track to support the relatively few driving wheels.  It became necessary to spread the weight over many wheels as speeds reached 90 km/hr.   European designers turned to the four-wheeled truck as being the solution to stability problems as well as keeping wheel loading within existing track limits.

Starting in 1912 in Prussia, more than 500 T-18 / BR 78 “Baltic” 4-6-4Ts were constructed.  In 1920, all of the railways in the German empire were united. An office in Berlin was established to unify future locomotive construction for the new Reichsbahn system.  Owing to the phenomenal success of the BR 78, another 4-6-4T configuration, known as the BR 62, was selected to be designed and built later in that decade.

The design of the BR 62 was based on that of the BR 78, however many astute improvements were made such as moving the water tank away from the drive wheels.   Such a configuration causes the adhesive weight of the locomotive to remain fairly constant during as run since the trailing trucks primarily supported the water tank contents.

The massive boiler could deliver steam at a rate that developed 1680 HP.  As the BR 62 was ready to go into full production, a serious economic crisis occurred in Germany during the late 1920’s and Henschel built only 15 at their Kassel works in 1928.  Despite the locomotive’s excellent performance, the Reichsbahn could only afford to buy two and the reaming 13 were not purchased until 1932.

BR 62s operated during WWII; many survived those terrible days and continued to operate until 1956 in West Germany and possibly as late as 1976 in East Germany.  Technically, the locomotive was a complete success and had “the most beautiful architecture of all the unified locomotives”.  Aster selected BR 62 No. 015 as the prototype for their Gauge 1 model.  It is the sole surviving example of this great locomotive.  

Specifications

Scale / Gauge          1/32, Gauge 1

Weight                        5.5 kg  (12.1 lbs)

Dimensions

Length O.B.                535 mm (21.1”)

Width                          97 mm (3.8 “)

Height                         143 mm (5.6 “)

Wheel Arrangement

4-6-4 (Leaf Spring Action)

Drive Wheels             55 mm dia. stainless steel

Pilot Wheels              24.5 mm dia. stainless steel

Trailing Wheels         24.5 mm dia. stainless steel

Cylinders                  Two double acting cylinders with crossported

Dimensions               Bore 12 mm, stroke 20 mm

Valve Gear                 Heusinger

Steam Port                1.5 mm, cut off at 84% stroke

Lap                             1.0 mm, travel 5.0 mm

Boiler                         Type “C” alcohol fired

Water Capacity         280 cc 80% full

Pressure                    3 kg / cm 2 (normal working)

Fittings                       2 safety valves, 2 super heater tubes, pressure gauge, water gauge, blow down valve, throttle valve,  blower valve, bypass valve

Axle Driven Pump     Mounted on the Lead Driver Axle

Dimensions               Bore 5 mm, Ram stroke 6 mm

Lubricator                Roscoe Displacement type mounted on the smoke box

Burner                      Three wick alcohol

Water Tank Capacity

300 cc, hand operated mounted pump with bore 8 mm, ram stroke 6 mm.

Fuel Tank Capacity 

140 cc 200 proof methyl or ethyl alcohol

Minimum radius      2 meters (6.5 feet)