Sunday, April 29, 2007

A question of sanity

Southern Railway(steam) engine 1256 is documented as having run on the Murphy Branch so I'm
thinking about getting a good "representation" of this very engine.
Hence I'm questioning my sanity since the closest thing in N is a light USRA Pacific which has some real differences in the way it looks..

I'm researching right now the possibility of "bashing" this engine
(1256) in N scale with the upgrade to 24*26 cylinders.

So my first step was to go hunting for some "critical" dimensions, such as dome diameters and boiler dimensions. Pulling out my trusty Ranks&Lowe and my Prince (technical guides) I then cranked up my digital calipers. My eyes may not be what they used to be (or my math skills) but some findings (note I'm leaning towards the numbers in parenthesis)


Steam dome diameter= 35.52 (35.5)

To show why one should question my "snity" that 35.5" SCALES DOWN to .221875" for N scale.

sand dome diameter= 32.2 (32.25)

diameter of boiler:
under the pop valves =78.63184 (78.5)
steam dome = 75.7897 (75.75)
sand dome = 72.71077 (72.75)
bell 68.6844 (68.5)
smoke box 71.05 (71.25)

of the above (calculated) dimensions the ONLY one in the drawings is the smokebox diameter which is 71.25. That would "possibly" indicate my eyes and method aren't too far off.

Now remember, once I decide that it is enough information available I've still got to build a lot of stuff. For instance, that dome that I mentioned above has to be "turned" down and then given the proper shape and then attached to the proper place on a boiler. And I've got to have enough space inside it for a motor and I've got to "hopefully" use a mechanism (wheels and frame and running rods) that already exists.

The majority of folks wouldn't know whether my "locomotive" is accurate or not. Damn, I'm not even positive that this loco ran on the branch in June, 1942! I'd better see if I can document that FIRST!