Kato Unitrack - Help with geometry!

Discussion in 'N / Z Scale Model Trains' started by kpoole, Nov 19, 2007.

  1. kpoole

    kpoole Member

    Hey all! I'm a Unitrack newbie, working on a smallish layout (3 ft. by approx 6ft.) I'm running 11" radius curves at one end, and would like to run a passing siding around the outside of that (picture turnouts right before the entrance and exit of the curve). Can someone help me with the geometry for that using #6 turnouts? I've been playing with Xtrkcad, and have the basic layout, but I haven't been able to get the geometry correct for that outer loop siding.

  2. kpoole

    kpoole Member

    Updated attempt with Xtrk

    Here's what I came up with in Xtrk. Some of you may notice that I couldn't quite get the geometry on my right side curve to line up exactly. I'm hoping there's enough wiggle with the Unitrack to make that fit! Suggestions welcome! For reference, I've kind of hybridized (is that a word??) the "Small Slice of the Pennsy" plan and the "Carolina Central" plan. I don't quite have enough room for a full 80" door, thus the compromise at 6 ft. I am planning on doing a mountain tunnel on the right side curve, with the interchange spur exiting behind it to the right.

    Attached Files:

  3. I'm at work, so I didn't upload your exact plan, but if your left side, inner (main) track is 11" radius, than you are probably somewhere between the 12 3/8 and 13 3/4 radius for the passing siding. You could certainly go with the 12 3/8 radius curves and then mess with the straight section length in the middle of the curve to get it right. You can also use a couple of the bigger radius curves as an easement, then go to the 12 3/8 for the rest of the curve. Try it with the 1st and last pcs of the curve at 13 3/4" and the middle ones at 12 3/8". You might find that works really well. Xtrk has those pieces modeled correctly, so you should get a good feel for what it will be like.

    There is a lot of allowable slop in the assembly of the actual parts in the real world, so you don't have to get them perfect. I have one spot on my layout which "shouldn't" work according to Xtrk, but actually works fine with no noticeable effects in the real (N scale) world.

  4. kpoole

    kpoole Member

    Figured out the runaround, courtesy of Drail

    Hey all, check out the attachment. This is what I came up with for the runaround. I wound up using Drail, instead of Xtrkcad. It appears that Xtrkcad is missing some of the Unitrack pieces, from what I could find. I'm using Drail in demo mode, but it certainly did the job! I'm planning to do the layout in stages, as $$$ allows to buy turnouts and track. The initial loop and lower spur will be first, followed by the runaround. Now, if only Christmas would get here soon, so I can surprise my 8 year old with "our project!"

    Attached Files:

  5. kpoole

    kpoole Member

    Any input before I order?

    Hey all,

    Just wondering if anyone has any input, good or bad, on the plan I came up with (see previous post). I'm getting ready to do the initial order for the first phase, and want to make sure I'm not overlooking something that will come back to bite me later!
  6. PWRR-2207

    PWRR-2207 Rogue Islander


    Are you still going to do it in stages? If you are, what are you attaching the track to and with (such as plywood with contact cement) and can you remove it to add the next section without any damage?

    You planning on a mountain and tunnel in a corner?

    Other than that, it looks good to me as you have room to put stuff, easy to reach without banging into things near the track, and the s turns are very broad.
  7. kpoole

    kpoole Member

    The table will be a shortened door, with 2" Foamboard. I may try tacking some caulk or something else removable here and there to hold things in place. I am planning on stages (the main loop and bottom inside spur being first, then the left side outer passing, followed by the upper inside spur and interchange spur). I'm hoping to purchase all the
    track over the next 2-3 months total. I am planning on a mountain tunnel on the right side curve, with the interchange spur going behind it at the top, which would be the shorter part of the mountain (in my head, anyway!)
  8. kpoole

    kpoole Member

    Pictures Always Help!

    Maybe this will help to picture the "stages" i'm thinking. The red will be the first stage, followed by the dark blue, then the green. Basically, I'll remove the straight sections, drop in the turnouts, and wire from there. Or at least, that's my plan, for what it's worth!

    Attached Files:

  9. PWRR-2207

    PWRR-2207 Rogue Islander

    A plan

    Sounds good to me :thumb:

    Good luck with the phases!

    PS: 'Phases' was not my original plan for my rebuild but it has turned into 'a little here, wait for part to arrive, a little there, wait...' which has been a good thing as it is more relaxing than my typical 'goals and objective' style project management approach to life ;)
  10. kpoole

    kpoole Member

    That's my style too....if I'm given a project at work, I want to know the overall objective, and goals, or it's pointless to me! :mrgreen: Of course, working on this with my 8 year old will help minimize the "goals and objectives" as well...I can hear it now, "Dad, quit tearing stuff out, I just want to watch the trains go!"
  11. Triplex

    Triplex Active Member

    I see you're following Linn Westcott's old advice: If you're building a plan with sectional track, it can look stiff, so try skewing it on the table.
  12. kpoole

    kpoole Member


    I have played with skewing it on the table. Ultimately, I may lay it straighter, and try to break it up with landscaping. We'll see. I've actually changed the plan slightly again, connecting the bottom spur back in, giving me a full siding there as well. I've got to measure my available space to confirm that this will work, as I lengthened the layout to the full 80" length of the door.
  13. kpoole

    kpoole Member

    Updated Plan - 30" door

    OK, Here's the deal. I've been offered as many doors as I want from a co-worker for free. They're remodeling the upstairs (he's a modeler too, and he's keeping some of them, but they have over 10 doors to do something with). The widest are 30" doors. I've played with the many plans I had tweaked with Drail, and keep coming back to the Carolina Central as the basis. I've attached what I think will fit. The catch is, it's within 2" of the edges on the long sides. I'm planning on the side that's the top in the picture being hidden staging. Would I be better off shifting 1/2 an inch to the top, or should I try to widen the door? I wish they were 32 or 36 inch doors, but it's a freebie!

    Attached Files:

  14. bill937ca

    bill937ca Member

    The Japanese language Kato @ Railfan web site has a series of track
    configurations for stations, yard leads, and changing the track center from 33mm to 49.5mm. Track part numbers are provided for each diagram. Station layouts follow Japanese practice.

    [KATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh

    District terminal [KATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh

    Yards [KATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh

    49.5mm track ctr [KATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh

    Ground station [KATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh

    Island station [KATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh

    49.5mm to 33mm track ctr ATO@Railfan] ‚¨‚·‚·‚ß»•iw“üƒKƒCƒh
    This also includes several crossovers.
  15. thumsup

    thumsup Member

  16. dwyaneward

    dwyaneward New Member

    Check out the Xtrkcad Yahoo group http://groups.yahoo.com/group/XTrkCad/files/ there are updated Unitrack parameter files in the file area under "Dwyanes Parameter files"
  17. kpoole

    kpoole Member

    Thanks! I've also discovered and have been using Drail, which works well. It's not free though. The demo lets you place up to 50 pieces on the table at once, which worked for my smallish layout.

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