Not sure I understand your question, but the SD40x was built on an SD35 frame. Maybe the door arrangement was changed at that time, for the experiment, while the stock SD35 maintained the current hood/door arangement. ?
The Atlas model would be the stock SD35.
Mike.
My You Tube
Hi All,
I am planning a build of one of the EMD SD40x test bed units, which became Union Pacific 3046. I have an Atlas/Roco Yellowbox SD35. My issue is with the door arrangement in the radiator section.
As far as I can tell, the doors on all prototype photos of SD35s seem to show 6 doors arranged in a 1-2-2-1 pattern. This is the same for the last 2 SD40x units, UP 3046 and 3047.
http://www.rrpicturearchives.net/showPicture.aspx?id=5399210
However, my Atlas SD35 has 7 doors in the radiator section, in a 1-2-2-2 pattern (from front to rear). Is this a glitch? A quirk of the old Atlas/Roco tooling? Is there any prototype reference to this?
https://tycotrain.tripod.com/atlashoscaletrainscollectorsresource/id4.html
I've accepted that I am going to rearrange the doors on my model using Cannon parts to match UP 3046. I am just more curious about the link between prototype and model. Any guidance is appreciated.
Mike