Double Figure 8 New Layout Idea

Massey Jun 1, 2020

  1. Massey

    Massey TrainBoard Member

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    Hey guys. OK so my small layout is great and all but kinda boring in reality. I do love watching trains but I want MORE! I have a desk I never use and if I remove that and the railfan layout I gain just about 10 feet of layout space.

    My idea is a double figure 8 that has a large station below with a 3 track "yard/passing siding". To the left is a rural area that I may put a small station/depot at and then to the right a city that will have an independent tram that goes from the city to the Lower station. No station in the city area hence the need for the tram. The train will go to the left or right and around the loop to the upper level which will have another large station and it will be another city with backdrop buildings. It's a passenger layout with a little action.

    I am limited by space more than anything else. I want continuous running for those days I just want to watch trains, and I don't want a simple loop, and I like the idea of multiple elevations. The tracks are Kato Unitrak. The grid squares are 8" for those who are looking at dimensions.

    So what do you all think about this layout? What could be better? What part is horrible?


    Dogbone.jpg
     
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  2. Inkaneer

    Inkaneer TrainBoard Member

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    Are the crossings at grade or is one track elevated over the other?
     
  3. NtheBasement

    NtheBasement TrainBoard Member

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    Assuming the crossings are not at grade, the hills will be pretty steep.
     
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  4. Massey

    Massey TrainBoard Member

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    I took the elevation markers off, sorry. The right side is a concrete viaduct as a bridge, the left is a tunnel. The rise is only 2 inches and the grade is 2.1% on the right and 2.5% on the left.
     
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  5. Inkaneer

    Inkaneer TrainBoard Member

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    With the tight track curvature which I estimate to be around 11 inches, your effective grade is greater than 2.1 or 2.5%. It appears that you have room to expand the radii of the turns. That would lower the effective grade but it is still tight especially if you are running passenger operations.
     
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  6. Massey

    Massey TrainBoard Member

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    The loops are Kato 282. My next larger size track is 315 which makes the layout a bit over 11' long which is too long for my area. I have already built this on the floor with both the 315 radii and the 282 radii and the 282 was the only one that fit my given space. I have not mocked it up as a running layout yet. I would prefer the loops to be 315 or better yet the 348 but I simply do not have the room. My railfan layout has 282 radii on the lower level and my passenger trains negotiate it just fine... alas that is also not on a grade.
     
  7. acptulsa

    acptulsa TrainBoard Member

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    Be forewarned: Steep grades (yes, 2.5% is steep) and 270° curves are a dangerous combination.
     
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  8. Inkaneer

    Inkaneer TrainBoard Member

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    The 315mm radius is only 33mm larger than the 282mm. That's about 1 19/64 inches so your end loops with 282R have a diameter of 22.2 inches while with 315R curves the diameter would be 24.8inches. You state in your first post that the grid squares are 8 inches. I count four grid squares at each end. That's 32 inches. Maybe the grid squares are only 6 inches??? Kato 348R track has a diameter of approx. 27.4 inches which would also fit on a 32 inch wide space. Looks to me that you only have a 24 inch wide space to work with. If so then I would say unfold the dog bone track plan eliminate the crossovers getting rid of the over and under.
     
    Last edited: Jun 1, 2020
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  9. Massey

    Massey TrainBoard Member

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    Wide is not the issue, long is. The grid is 8". With the 315 radii I measured the track end to end at just over 11', not counting any extra for benchwork. With that length I cannot open a cabinet or drawer that would be at the end of the layout, even when recessing the benchwork 3 or 4 inches under the layout. As it sits the table for the layout will be 128" or 10' 8" that is the absolute limit I can go with the room I have. If I make the "yard" area any smaller I lose the ability to run a passenger train of 5 cars without fouling the main. I plan on keeping 2 trains on the tracks plus one tram. I did play with the dimensions and tried using different radii 45° turns in the entrance to the loops, but nothing saved me much space. Yes I would really like to use my 348 radii as I have a whole mess of them and I will use all the 282s I have leaving nothing for spares.
     
  10. Inkaneer

    Inkaneer TrainBoard Member

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    I wish you would have mentioned all that in your first post. Sounds to me that you are committed to this track plan but since it is Unitrack you can always pick it up and redo it if you are not satisfied.
     
  11. Massey

    Massey TrainBoard Member

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    I thought I did mention the 10' side was not negotiable but I didn't. I was thinking it when I wrote the first post but just said that space was limited. Anyhoo I am not against making changes and thankfully that is what Kato Unitrack is good for. When the benchwork is complete I could try again to make the curves larger but I don't know how that will be. That being said I wanted input before building the benchwork, as that will pretty much limit my abilities once that is made. I am currently planning on standard tabletop type benchwork with pink foam for scenery and elevations the legwork will be bookshelves on the larger ends with a drawer for the controls in the middle and more shelving under the middle. All this built by me, no commercial shelving. I am debating open shelving or solid sided, leaning more to the open shelving for ease of access.
     
  12. Maletrain

    Maletrain TrainBoard Member

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    I am not seeing the problem with making larger curves while keeping the same siding length. I don't have time to go draw things in Anyrail and export them to show you here, so I will try to substitute less than 1000 words for the picture.

    1. Instead of having the left side turnout going straight-through to the middle of your 3 tracks, try a left-hand turnout so that the straight path comes down from the upper left and the diverging path turns into the middle track and the straight through path connects to a curve into the bottom track. That can give you even longer sidings. (You could even use 2 LH turnouts on a diagonal path to turn to both the top and middle sidings, with a final 19" radius curve to the bottom siding.)

    2. You can do a similar thing on the right side. That gives you a much better flowing plan, too, with less "S" curves, plus it should give you a way to make the curves bigger without shortening the sidings if you don't try to make the sidings longer.

    3. When using small radius curves, they both operate better and look far better is some larger radius sections start the curve as "easements". I use 19" radius 15 degree sections on each end of 15" and 13-3/4" radius curves. It adds almost nothing to the diameter of a 180 degree turn, but it does add some noticeable length. You do seem to have a lot of margin to the edge of your table, so I think you may have some room to use easements. Because even #4 turnouts are equivalent to 19" radius in Unitrack, the suggestions in (1) and (2) above effectively have some easement on the lower level end of your curves. There seems to be enough straight sections in your track going over the lower track to put some easements on the other end of the curves, too.

    4. Because your upper level straightaway is longer than your lower level passenger siding, I am thinking you could also stand to shorten that a little to get some easements or just larger radius curved sections leading to there, too
     
  13. Massey

    Massey TrainBoard Member

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    I will give that a try, prolly not till this weekend, as I have to tear my dining room apart a bit to set this all up.
     
  14. NtheBasement

    NtheBasement TrainBoard Member

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    Can Unitrack can go from 0% on one track to 2.5% on the adjacent segment? If so can your locos handle the abrupt change in grade? If not, part of your loops have to transition from 0% to steeper, which means it will be > 2.5% on the remaining segments to make up for the vertical transition segments... you get the idea. @Inkaneer's advice about unfolding the dog bone to an oval is a good Plan B.
     
  15. Maletrain

    Maletrain TrainBoard Member

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    OK, I had a chance to play with Anyrail. Here is a plan that uses 13.75" minimum radius, #6 turnouts, and has 19" radius easements. It fits your footprint, and has the same opportunity to make stations on 2 levels. I did not put in the tram railway, but with the right hand loop now not crossing itself, there should be plenty of room to put a tramway wherever you want, and at any elevations you want (tram grades can be really steep). I also added a turnout on the bottom siding that could go to an industry, even sneaking under the mainline into the left hand loop if you want to do that. A similar turnout on the top siding going into the right hand loop is also possible. I exported this as a jpg to load to this post, and that lost all the track section info. If you want the Anyrail file, send me a PM with your e-mail address and I will send the Anyrail file to you. Also, you may note the slightly jagged connections on the 3 siding tracks, in their middles. Don't worry about those - when you lay the actual track, those tiny misalignments don't matter a bit. I did not figure the elevations, but I think I reduced your necessary maximum grade. I know that the larger radius will help when pulling up the grades.

    Massey.jpg
     
    Last edited: Jun 3, 2020
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  16. Massey

    Massey TrainBoard Member

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    Unitrack can indeed to that but nothing will be able to roll up it or down for that matter. My plan was to "bend" the first segment into the incline to allow an easement into the climb.
     
  17. Massey

    Massey TrainBoard Member

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    Thanks for the update, I will PM you when I get home, my work computers wont allow it. I will have to play with the setup if I get some time this weekend. I just found out I am getting a Waverunner to work on this weekend. Maybe even get to take it to the lake to "test" it out!!
     
  18. Maletrain

    Maletrain TrainBoard Member

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    One way to vertically bend the roadbed is to substitute a bunch of smaller sections for a longer section. For instance, the 9.76" section can be exchanged for four 2.44" sections. Trying to do that on a curve is much more difficult, because Kato does not make very short curved sections. The shortest curve section I know of is 10 degrees, and it looks like about 19" radius. So, you could substitute 3 of those for 2 15-degree sections of regular 19" radius track. But, those only come with other sections designed for the Kato turntable expansion. So, it would be expensive to do it that way.
     
  19. Maletrain

    Maletrain TrainBoard Member

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    Regarding vertical transitions: I measured what has to be the worst one on my fledgling layout, and it seems to be OK as-is. It is a single piece of curved track that raises the railhead 5 mm in a distance of 7.25", starting from a wye turnout and connecting to a Kato turntable. I have test run f units across t with no indication of any problem. So, it is basically a transition from 0% to 2.7% at one end and back at the other, on a curve. Haven't tried it with a 2-8-8-4 (which won't fit on the turntable anyway) or a really long diesel unit, yet.
     
  20. Massey

    Massey TrainBoard Member

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    I was running a similar experiment the other day. I put a pen under a 9" piece of track, the pen is about 8mm and my E5 was the only one that didn't like the major elevation change but that was more because the pilot hit the rails. It climbed the incline just fine otherwise. When I made a slight easement from the track before the E5 made it just fine. All of my P42s also made the climb with 5 cars behind them. I didn't calculate the grade but I figure it was over 2%. Hopefully this weekend I will get some train free time to lay out the track changes and I may try to build the entire loop with the inclines to see how the trains handle it.
     
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