We're going to build the locomotive and tender in two separate files, starting with the loco.
So, create a new file and call it locomotive001.3dc.
Why the 001 you ask? It's because 3DC is going to crash a lot ... be prepared for this! You need a lot of patience to put up with it. Whenever it crashes, as soon as you restart 3DC, say yes to recovering the unsaved document, and when it's loaded the recovered document, save it to a new file with the next number up. I always keep the last 20 or so saved files. I also save anyway, to a new file, several times a day. That's because sometimes, 3DC corrupts something that prevents it from reloading a file. It's very rare, but when it happens, it can seriously ruin your day. I've learnt the hard way to make these saves to new files (and keep backups of them in various places, on different hard drives, in different computers!) so that I won't lose more than a few hours work at the most.
This is going to be a 2-8-0. It's going to have 2 bogies. In order for the wheels, drivers and pilot wheels (and trailing wheels if the loco had them) to track the rails, they have to be placed in bogies. Our loco will have one bogie (called bo01) for the front, pilot truck (its wheels and truck frame and all other bits attached to the same), and another bogie (bo02) for the drivers.
Important note: As this is a rigid frame loco (not an articulated), everything that's attached to the drivers or the frame will be placed either directly in the bo02 group or into a child group belonging to bo02. That's so that when negotiating a curve, the main frame, boiler, cab, etc. will stay aligned with the drivers.
To create the first object group, drag a cube primitive into the scene:
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Click once on the newly created group and change its name to locomotive:
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Rename the cube to DO NOT DELETE ME. The reason for this won't become apparent until much later on, when we come to optimise the cab view, but doing it now will save a lot of headaches.
Go into top-down view:
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Then constrain the y and z movement, but not the x:
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Note: Constraining the movement in the x, y and/or z axis is something you have to get used to doing a lot, especially when selecting anything (objects, points, lines, faces) to avoid accidentally shifting things. It's horrible when you discover that you shifted a point without realising it, especially if you see that it happened days ago and has ruined something it took you ages to do. I always lock all three as soon as I open a file, and I only unlock them when I really do want to shift something, locking them again afterwards. Even so, I'm forever shifting things accidentally.
Shift the DO NOT DELETE ME cube over to the left, beyond the 10 foot wide grid, just so that it isn't in the way of our model to be. Then lock it. We should never have to touch this object again (but we will need to select it sometimes).
ScreenShot015.jpg
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