Over and Under Figure 8 track plan

Discussion in 'Track Planning' started by alexander, Nov 9, 2006.

  1. alexander

    alexander Member


    So, waddya think

    the bit in the middle is a passing siding of sorts

    down the bottom is a yard

    in the middle are my industries

    i may run it with my brother sometimes, me in the yard and him in the industries

  2. MasonJar

    MasonJar It's not rocket surgery


    Looks good. I would try to extend the top track in the yard as much as possible, even if it means using a curved turnout. Also, you may want to add at least one crossover at the left end of the yard tracks, so your train can pull in, and the engine can escape.

    From an operational point of view, it may be difficult to reach all those industry tracks from one side, especially if the crossing track is overhead, instead of "underground".

    What kind of industries do you have in mind?

  3. alexander

    alexander Member


    the Yard is as big as it can be.

    i was trying to get a "moutain climbing" feel, Thinking freelanced branch through Montana/Idaho/Washuington, that area

    Lumber, and and a small cattle loading point* will dominate the industry, with a team track and a small Oil well to round it out.

    *i know these may not be the NW's most well known industries, but they fit the plan

    these industries are acceptable i hope (i heard they are, i figure they can change)
  4. alexander

    alexander Member

    forgot to mention, there will be a series of short tunnels as you go through the line, and a veiwblock stopping you from seeing the yard

    I tried adding the yard crossover in, it wouldnt work, so, i guess we have some tricky movements to do.
  5. nachoman

    nachoman Guest

    keep in mind the grade is gonna be pretty steep if this is HO :)

  6. alexander

    alexander Member

    ya, i know that, but i can live with it, the size of it limits the lentgh of trains
  7. Jim Krause

    Jim Krause Active Member

    Alexander: What historical era are you modeling? If you are doing present day modeling, lumber is shipped on special flatcars. Not a whole lot of raw logs go by rail anymore, except for some areas here in Montana when there are timber sales due to forest fires. One product that ships by rail is wood chips for pulp and paper mills. They travel in high volume hopper cars. As for livestock shipping by rail, there isn't much of that anymore either. I've read that there are/were a few hog shipments in some parts of the US.
    In an earlier time there were log trains on the main lines of most railroads of the Northwestern US and lumber was shipped by box car, hand loaded. Some of the older boxcars even had small end doors for loading long lumber. Big timbers were shipped by flatcar.
  8. alexander

    alexander Member

    I'm thinking 1970s BN, as thats what i have equipment for, so most of this isnt a problem

    also serving the cattle will be a feed mill and some other rural structures, i'm going for a western theme here

  9. alexander

    alexander Member


    The whole theme is the same, just gave it a bit more of an "irregular"look

    added another yard track too

  10. LongIslandTom

    LongIslandTom Member


    Just a heads-up... The crossover section of your layout basically has 3 quarters of a turn to elevate the track to clear the underpass. That means with an 18"-radius curve, you got 18 x 2 x 3.14 x .75 = 85 inches of horizontal travel to elevate the track.

    To clear the underpass (accounting for the roadbed and the deck thickness of the bridge overpass), you need to elevate the crossover by at least 3.5 inches. 3.5 / 85 = .041 x 100% = 4.1% grade. That is very, very steep, and when you figure in the rolling resistance due to the very sharp curve, I think most HO engines out there will have trouble pulling even a short train of less than 10 cars up that incline.

    You might want to think about making the crossover loop with a wider radius to make the grade less severe. For instance, if you use a 22" radius curve, you get 22 x 2 x 3.14 x .75 = 103 inches of horizontal travel to elevate. 3.5" elevation will work out to a bit less than 3.5% grade, with an easier curve. It's still very steep, but at least your engines should have a somewhat easier time pulling a train up that incline.

    Food for thought! :thumb:
  11. Russ Bellinis

    Russ Bellinis Active Member

    If you are going to do an island type layout with access all the way around, you might want to consider a 5' x 10'. You could do that with 2 sheets of plywood with a bit left over, but that would allow the yard along side, and a longer climb=less grade with the 22 inch radius suggested and still leave room for the yard to one side. Depending on the location of the spurs in the center, you might need to make an access hatch or two. They could be covered by industry buildings that would be removed with the hatches when access was needed.
  12. fsm1000

    fsm1000 Member

    I have one hill that is 9% grade and am limited to only two cars which is fine for what I do. So 4% is steep but doable if you like short cars. :)
  13. alexander

    alexander Member

    Ok, thanks all

    some points that i forgot to mention:

    I'll be running short trains, yes, and i'm aware of the grades (i've done it before you see). remember, i'm limited by the size of my passing siding

    3.5" seems a little high, i was thinking 3" would do, but then your the experts i suppose. the highest i have is my locos and a couple of hi cube boxcars i plan on getting

    i doubt i can get any more room, my benchwork is already made.

    also, if its too steep, i'll do what the prototype does: add a helper
  14. Russ Bellinis

    Russ Bellinis Active Member

    If you are running cork roadbed with code 100 rail, the height to the top of the rail from the benchwork will be @ 1/2 inch. If you get your overheight boxcar and measure it and add 1/2 inch you will know how much you need to clear the car with a bridge. If you use quality locomotives with enough weight, they will not have any problem with a 3.5-4% grade. You might see the train trying to "overrun" the worm gear when going down hill.
  15. Triplex

    Triplex Active Member

    Now you have a problem the first version didn't have. After you climb the 3/4 circle on the left, you go into a curve the other way without any straight section.
  16. ocalicreek

    ocalicreek Member

    Most cheap locos that come with over-under figure 8 starter sets have no trouble pulling the cheap plastic cars that come with the set around the track, and that's usually with 18" radius curves and plastic piers. Now I've never done the math to figure the grade there, but if a cheap-o loco can do it, then that should be encouraging.

    Just remember to keep the grade as consistent and smooth as possible. John Allen actually made the grade a bit steeper at first (just like the prototype...according to Wescott) then evened it out so that the loco could get onto the grade and pulling steady before the rest of the train. But this was perhaps a unique situation (aren't they all).

    The plan kinda reminds me of the Cactus Valley that Frary built in a series of articles for MR.

  17. ocalicreek

    ocalicreek Member

    PLUS, JA's first G&D used 14" radius curves and steep grades...but was tailored for the equipment he planned on using.

    Either way, I think what you've got is a pretty cool plan. Go for it!

  18. alexander

    alexander Member

    yep, i read that article the other day, it was the inspraition for the oer and under theme.

    i'll see what i can do about increasing my area to work with

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