Build a Cooke 2-6-0 in 1:20.3, The MLS Rolling Stock Challenge! - (part 1)
Over the coming weeks we'll be showing the construction of a Cooke 2-6-0 at 1:20.3 scale. The Cooke Moguls
were introduced to the DSP&P in 1884 and after many rebuilds served the Colorado & Southern RR through to the 1930s.
They were a well designed large mogul, with a weight and tractive effort rivaling the Baldwin 2-8-0s of the day.
From a model maker's perspective, they are a plum locomotive prototype choice because the number of rebuilds and
upgrades done to the locos over 50 years resulted in some 10 or more different styles of loco to choose from.
LGB have represented the Cooke as they looked when delivered in 1884, and as they looked when retired. There
were also several different styles through rebuilds that occurred in the 1890s and early 1900s. The circa 1900
versions are among my favorite 'look' for the Cooke, so it is a 1900 era version that I will build!
I've planned to do this model for a couple of years and keep getting side tracked, so this MLS Challenge is just
the ticket I need to get this model done. This will be a loco actually built for me!!
These three photos show just three guises of the Cooke Mogul as seen around 1900-1904.
The style I will be building is the one with the straight stack, rounded domes and extended smokebox, the style as
seen on C&S #6.For model setout and construction I have two sets of drawings, published in MR in the early 1970s
and again in 1999. Neither are completely correct, but are good to scale the model's proprtions. Any Bernat has
also been very kind to supply copies of engineering drawings for an almost identical Cooke 2-6-0 built for the
Kansas & Gulf Short Line (a really cool looking Cooke with smaller drivers).
The Cooke 2-6-0s featured 40" drivers and the Bachmann 4-6-0 wheels, when scaled to 1:20.3 are 40". So that was
my starting point. The axle setout of the Bachmann 4-6-0 is also very close to the Cooke. The middle to rear
axle is a spot on match to the prototype, while the lead axle of the 4-6-0 is 6mm closer to the middle axle than
it should be for the Cooke. Thus by constructing the Cooke chassis around a Bachmann 4-6-0 drive, one can build
a very close to scale chassis, with the only compromise being the lead axle being set further back from the
cylinders. As it happens, Barry Olsen sent me a sample BBT 4-6-0 drive some time ago (which he had converted
into a 2-6-0 for me). This is the perfect drive for my scratch built 1:20.3 Cooke Mogul.
The first item of business was to change the counterweight style of the BBT 2-6-0 chassis. This was done
by applying 1mm thick styrene counterweights to the existing wheel sides.
The cylinders were fabricated from PVC pipe and 1mm styrene sheet (method is the same as used in my MC2002
series).
Since the Cooke moguls had both laird (single rail) and Aligator (double Rail) crossheads, I chose to make this
loco with the double rail type for reasons of creating a visual distraction over the incorrectly placed lead driver
seen behind! Big chunky Cooke crossheads will soon be made!
The pilot is one of my Mason Bogie Pilots as produced by Vance Bass. The size and style is perfect for my loco.
A 1/2" square wood rod serves as the pilot beam.
Work has begun on the firebox, made from 2mm styrene, with reinforced corners, and 0.5mm thick embossed outer wrapper.
still to be made.
Chassis leaf springs are made as a separate assembly, by layering up slithers of 1mm styrene strips.
OK onto some more pics about the Challenge.
Work on the 1:20.3 C&S Mogul has progressed. The chassis has been essentially completed, with scratch made crossheads,
made from two plates of 1mm styrene, with 3.2mm ABS square rods between. The ABS rods (packers) inside the crossheads
slide against the guide rails. The metal main rod is an ex K-27 main rod, from PSC, cut down to length and details filed.
The Stephenson valve gear cranks, external rods and connectors are in place. The chassis also has the brake gear and
cylinders added between the 1st and 2nd drivers only, per prototype. The brake cylinders are the vertical units just
above the frame. On the rear end of the chassis the cab supports have been added.
The big box headlight is a proprietory unit from Accucraft..the huge Colorado 23" lens headlight. The same lamp can be
scratch made from patterns in the MC2002 project. The cab floor was made from 2mm styrene.
The boiler was fabricated from a 62mm OD PVC pipe. To obtain the step between smokebox and lagged boiler, the same 62mm
pipe was split down the centre and spread over the 62mm smokebox/boiler pipe..the two clamping together. The smokebox was
then packed out 1mm, by wrapping a rivet embossed 0.5mm styrene wrapper over the exposed 62mm pipe.
