Curve Question:

Discussion in 'HO Scale Model Trains' started by MCD4x4, Mar 17, 2007.

  1. green_elite_cab

    green_elite_cab Keep It Moving!

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    yeah, you are out of luck as far as space goes. Passenger equipment is some of the most space taking type operations. I think the best thing you can do is maybe just leave out that ramp all together, and just have an elevated subway line that snakes around the front of the layout, and then goes behind a building or something out of sight, so that it seems like the train is gone.

    I think that the subways can handle tighter curves, like an 18 inch radius, so that might work. the ramp just seems to take up to much space, and i didn't think subways usualy connected with the other railroads.


    as for the bottom, you can try and fit lines like the North Jersey Coastline, or which ever larger rail transit and such in there on 22 inch radious tracks.

    there just isn't alot of space fore anything.
  2. MCD4x4

    MCD4x4 Member

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    Maybe this will help, The sides are a 1/2" high, if the ramp can come off the curve and be that high by the time it hits the back, the ramp can actually be above the side rail which would give us another 2" in the back, making it 49 1/4" deep. Would that hook a brother up? Would the extra 2" be enough room for the ramp? To gain this, the switch would absolutely have to come off that rear right curve.


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  3. planeshavings42

    planeshavings42 Member

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    Layout

    HOW ON EARTH DID YOU MAKE UP THIS SUPER LAYOUT PLAN? DO YOU HAVE SOME SORT OF SOFTWARE? :) PLEASE ADVISE Duane Hampton E-MAIL: planeshavings42@gmail.com
  4. jetrock

    jetrock Member

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    Nonsense! Build AROUND the four-poster bed: make a couple of notches for them, and mount a narrow (maybe six-inch) shelf in front of the posts. The plan below is just a schematic, but a 6" shelf is enough room for a double-track mainline with subway wall behind it (pretty easy to make out of Masonite, spray paint with gray primer and weather with ink, HO scale graffiti, and a little grime) and even have room for a surface or elevated line above it. The 1' wide sections are enough for a long two-track storage yard in front of your two-track mainline, which is enough room to store a dozen or so subway cars, and the section along the back wall is long enough for a "nolix" (basically, a long ramp) from one corner to the other, allowing a smooth transition from the lower subway level (or surface level) to an elevated line.

    green_elite_cab: Many subways also have surface line segments. Chicago's Red Line starts as a subway downtown, then turns into an elevated railway.

    Attached Files:

  5. green_elite_cab

    green_elite_cab Keep It Moving!

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    yes, i know that, but I mean, in general the subways don't run on the same tracks that NJ transit or Amtrak would be running on, right? I would think they'd have their own seperate lines and trackage for the most part.
  6. Spawn of Chaos

    Spawn of Chaos Member

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    Eh, high shelf w/ swinging sections attached to the doors or something *could* work. I don't know, I've never tried lol...
  7. MCD4x4

    MCD4x4 Member

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    When you say a 22" curve, or an 18" curve, does the number represent the width of the circle? One of the choices below?

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  8. prodigy2k7

    prodigy2k7 Member

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    No its double..
    Thats an 18" diameter, People talk about 18" radius, which is half of that.
    [​IMG]
  9. MCD4x4

    MCD4x4 Member

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    So an 18" curve, takes up 36" ?







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  10. prodigy2k7

    prodigy2k7 Member

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    From one side of the half-circle to the other, yes

    I have a 4x8 table. 4 feet wide = 48 inches...
    Hal of 48 inches is 24, due to the width of the track itself, My maximum radius can be ABOUT 22"

    PS: I took photographs to better understand how to use a yard stick to draw a radius.
    I will upload in a moment...
  11. prodigy2k7

    prodigy2k7 Member

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    My pivot point is the big giant screw, you can use a small nail but I only had this, plus its easier to hold and not move...

    Notice its at the 1" mark. Not the 0" (for obvious reasons)

    Lets say you want a 18" radius, since I started at 1" and not 0", I use 19" on the stick, instead of 18" make sense? (Note the hole at 19" mark)

    I have a big hole cuz I used a marker =P lol...

    The bottom two pictures represents drawing a 18" radius. Note the pivot point doesnt change and you just draw a line with the marker.

    The finished product is an 18" radius turn.

    Thats how we get the numbers. :)
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  12. MCD4x4

    MCD4x4 Member

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    OK, I get it. My next question is this... If an 18" curve takes up 36 inches, why can't I use another 18" set of curves with a piece of straight track in the center of it to get the outer line 2 inches further out? Thus, not having to use 22's and max out my space. This way I could have one at say 43 and the other at 45 than the ramp? this would work.







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  13. Ralph

    Ralph Remember...it's for fun!

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    Hi MCD4X4,

    Yes you can do that. You may find that a larger radius curve like 22" will look better as a double track around the 18" radius curve and some longer equipment might have derailment problems negotiating the curves and small straight segment. Experiment with it without glueing or nailing things down and see what you think.
    Regards,
    Ralph
  14. MasonJar

    MasonJar It's not rocket surgery

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    An 18" radius curve takes up about 38", since the radius is measured to the centre line of the track.

    You will also need more space between parallel tracks on a curve than on a straight. You might get away with 2" on straight track, but would want to bump that up to maybe 2 1/4" for tight curves (e.g. 18"), especailly if your rolling stock is long, and hangs over the curve.

    See www.nmra.org standards for more info.

    Andrew
  15. MCD4x4

    MCD4x4 Member

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    OK, I'm going to fool around with this plan. My next question is.. going with Jetrocks idea of moving the ramp switches to the curves, and going with 18", (pictured below) what is the name of the switches I need to do that? How would I ask for them in the store? Also the yard switches? Thanks guys.







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  16. jetrock

    jetrock Member

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    They are called Atlas Snap-Switches. That's the name in the Atlas catalog. If you are using Atlas RTS software, the names for the products in the store are the same as the names of the pieces you are using in the program.

    If you're going to fit a double-tracked loop AND a ramp upward to the upper level in 48", you're going to have to use 15" radius track on the inside loop, and 18" on the outside loop, then a separate 18" curve for the transition to the ramp.

    That radius measurement is from the center of the circle to track CENTER--which means that an 18" radius curve requires more like 20" of space to hold track and train--more if it's double-tracked and you need clearance between tracks.

    I really, really suggest that you give an around-the-room at least a look. Have you considered that maybe the reason your daughter doesn't use her existing set much is because it's wedged up next to the ceiling and she has to stand on a chair just to see it? A layout at chest or shoulder height that goes around the room can take up LESS space, be MUCH LESS hassle to build and operate, and is MUCH easier to access.
  17. prodigy2k7

    prodigy2k7 Member

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    Technically its not parallel on a curve, it is adjacent.
    parallel are two line segments that never touch as far as they go.
  18. MasonJar

    MasonJar It's not rocket surgery

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    One circle inside another (i.e. different radii) with the same point of origin never touch. Two lines in different planes never touch either, and they are not parallel.

    ;)

    Andrew
  19. MCD4x4

    MCD4x4 Member

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    I can't do the shelf thing. The shelf would have to be 63 inches high. I also have two doors and a window in the way. I'm thinking the best way to go is with the 18 inch curves and two crossovers with the ramp coming off the 18" snap switches in the rear.

    The ceiling is 83 1/2" high. The two doors and the window are 2 1/2" lower than that. Once the track up there became dusty, she would play with the train on a single track line for hours on end. Running a four car NYC subway or a trolley that backed off on to it's own siding. She would park the train on one siding and bring the trolley off another. That's why I would like to expand the yard tracks, she enjoys bringing them in and out. The DCC will add to the experience too..

    I wish I could have picked up the track at teh show, there was a guy there selling suff pretty cheap.

  20. jetrock

    jetrock Member

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    If you're dead set on 4x8 land, then the inside track of your two-track mainline will have to be 15" radius curves. So, here it is...I scooted the track away from the edges, since the layout has walls on two sides--if you butt the track up against the wall you won't have room for the train (the train is wider than the track) and it will derail every single time. The inner radius should be 15", the outer is 18". The upper level should be pretty self-explanatory.

    For the ramp: Use a 2% grade for the curves, and 4% risers for the ramp itself. The 2% risers allow a slightly more gradual rise, transitioning into the 4% grade, and you'll end up with an upper level about 3" above the lower level.

    For the yard: I added a switchback track allowing you to store two more trains, and moved the switch over to provide a little bit more length. Remember, in yards longer body tracks are generally more useful than more switches.

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