I am searching for dimensions on the radiuses of the nose of E/F units. I can find top and side view drawings of engines but nothing about what the compound curve is on the nose. I’d like to see actual dimensions if possible rather than having to extract them from on line drawings rather than original prints. I am trying to draw one up in 3D in Inventor. I am wanting to build a body from scratch in ridable 1/8th scale rather than buy a body and I have a friend who models in 1/22.5 and wants to build his own. Does anyone out there know what the radiuses of the nose are?
I would buy a good HO model (like a Highliner shell) and then use that as a model to start sculpting one. Maybe use a blue foam core and then cover it with plaster or clay. When you get the shape you want, then you can make a fiberglass mold of it and then cast a fiberglass nose.
Dave H.
That’s actually exactly how I’m going to build the 1/8th scale body. I’ve got tons of fiberglass experience. I am drawing it up in Inventor for a friend though. I can give him a 3D rendering of it and he has a neat machine which an basically “print” it in 3D. Somehow this machine uses small plastic cubes that it melts and then builds a 3D model in layers. Neatest thing I have ever seen. I do need the dimensions though for an accurate representation. I have an F unit in N, HO, and even a Lionel version but each one has differences when scaled up. The n really isn’t big enough to measure but the HO and Lionel are different. The real dimensions would be nice. That way I can scale it with the click of a mouse button. There are a pair of real F7’s in the museum down here but now the issues is that they are too large to get good measurements off of as I can’t climb all over them.
The problem is that they are multiple compound curves in 3 dimensions. So there is no one radius to the nose. nominally the engine is about 10 ft wide, so its close to 5 ft radius, but the actual radius may vary from 20 ft to 2 ft (just guesses). What you really need is a contour map.
The way to do the real F7 is to build a scaffold over the nose, then get one of those rotating laser levels and put it in front of the engine. After dark, raise the level in increments of 6 in or so and then take a picture on the nose looking straight down from exactly the same location. the laser will trace the contour on the nose, print out a picture and trace the laser outline to get the nose contour. Setting the laser vertically and putting camera on one side, and moving the laser in 6’ increments towards the center of the engine will get vertical contours.
Dave H.
Real F-unit and E-unit noses are made piecemeal of framing, sheets, and about 20 gallons of bondo. That nice flare around the nose headlight is all bondo from the cast headlight trim ring all the way out to where it feathers into the sheets. This is said from someone who has had the misfortune of repairing and rebuilding noses ruined by corrosion and collision.
RWM
After studying the models, the compound curve should be pretty easy to get right. I just need the radiuses of the nose as seen from a front view, side view, and top view. The front and side don’t seem to be that hard to find but the top view has been more difficult.
Which F? F3s are shaped different than F7s
You sure? As I recall from my greasy EMD parts catalogs, F3/7/9 carbody parts were all identical except for things like portholes, air-filter grilles, and some other bric-a-brac. FTs were certainly different.
RWM
No. Not entirely. But I was thinking 3s were more blunt bulldog style than the streamlined F7
The F7 is what I’m after. I still haven’t learned to tell the physical differences between models.
then work with that. I haven’t relally either, just passing thought to ya. Scaling: Honestly, go with the HO measurements. Why? HO has usually been known for a little longer for more accurate models. Dunno why, just has.
That pretty much leaves it open to the guy shaving the Bondo! 
It would seem there is not a set spec for the nose, except for the designers drawing. There’s a big +/- factor involved between the draftsman, the fabricators, and the Bondo shavers.
If you get it close enough, that’s probably good enough!
Rotor
f:
Talk to the museum curator. Maybe they’ll let you bring a ladder and take measurements. It’s a locomotive; I don’t think you’ll hurt it. 
F2 through F9 noses were the same - the very accurate “Highliner” shell allows you to model any F unit except the FT.
However, E units did change. Up thru the E6 the nose was much more slanted, the lower part stuck out much further than on an F unit. E7-8-9 engines had a nose much more like F units, maybe even identical in curvature.
I know the museum director but I don’t think he’ll let me literally climb all over it. It’s an insurance thing. I can get some measurements. I’ll try to scale off of my models first and see what happens. If it looks relatively close, I’ll be happy.