24" curve radius capabilities

Discussion in 'FAQs' started by Bob Collins, Feb 2, 2001.

  1. Drew1125

    Drew1125 Active Member

    Joined:
    Jan 28, 2001
    Messages:
    3,154
    Likes Received:
    0
    Bob,
    You need an ABSOLUTE MINIMUM of 3" overhead clearance in HO, measuring up from the RAILHEAD. 4" would be even better to shoot for, especially if you're running large equipment. i.e. auto racks, or double stacks. You'll also need at least 1-1/2" side clearance on straight track, measuring from track center. You'll need more than that on curved track to acount for overhang.
    Also, one of the best things a model rairoader can invest in is a scale ruler. I can't imagine doing any project without it. They come in a couple of different types. Get the metal one if you can. It measures distance in scale feet for HO, N, O, & S scales.
  2. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    How about Hackensack & Boise! Just love the names that's all. I'll go there one of these days. Just cause I like the names! [​IMG]

    Yep. millimetres (spelt RE on the end) is good to work with. Easy to multiply out etc. Try adding 1 3/8" + 2 13/16" + 5/16" + 2 1/2" ! Ummmmmmmmm....

    Australia converted to metric 20 years ago. As a bit of trivia. rulers with metric one side and imperial the other were a banned import. Yet imperial persists. The only things left are people's height (refered to as feet/inches) and baby's birth weights. pounds/ounces. Dunno why, but those two still persist.

    TOOT!
  3. Bob Collins

    Bob Collins Active Member

    Joined:
    Feb 2, 2001
    Messages:
    1,023
    Likes Received:
    0
    Talk about being a long way apart... that would be Hackensack and Boise... Sort of like Sydney and Perth or Darwin and Adelaide!! I'm disappointed to learn you don't still weigh in stones..my, my!!

    I will look into getting the proper scale. So far I have been fortunate in getting things right with benchwork and subterrain. Have put down about 30' of cork without any problems. I work in one place for awhile and then more over somewhere else. As big as this layout is I feel like I'm going into another room when I go to the other end!! Hope I never, ever have to try to move it!!

    Bob
  4. shamus

    shamus Registered Member

    Joined:
    Dec 17, 2000
    Messages:
    3,688
    Likes Received:
    0
    16ths of an inch to decimal
    1 = .0625
    2 = .1250 = 1/8"
    3 = .1875 = 3/16”
    4 = .2500 = 1/4
    5 = .3125 = 5/16”
    6 = .3750 = 3/8”
    7 = .4375 = 7/16”
    8 = .5000 = 1/2
    It is easy to work out anything from inches to decimal with this simple chart
  5. Bob Collins

    Bob Collins Active Member

    Joined:
    Feb 2, 2001
    Messages:
    1,023
    Likes Received:
    0
    Shamus;

    Thank you very much. I will copy it all down and post it on the bulletin board I have created next to my layout to hold just such materials.

    Bob
  6. shamus

    shamus Registered Member

    Joined:
    Dec 17, 2000
    Messages:
    3,688
    Likes Received:
    0
    Bob,
    Don't forget to make transition curves on your layout.
    A transition curve a way of reducing the angle of attack into a bend.
    Blue line normal curve, RED transition curve.
    I have posted this before, but don't know if you saw it.
    http://www.badger-creek.co.uk

    [​IMG]



    [This message has been edited by shamus (edited 05-05-2001).]
  7. George

    George Member

    Joined:
    Jan 2, 2001
    Messages:
    532
    Likes Received:
    0
    Bob,

    The bridge kit I mentioned should give you more than enough clearance. If it's not quite the desired height, you can shim it up to whatever you want by fabricating a wooden pier and putting it underneath the pier included in the kit. The arch is concave, not convex like the ATLAS and FALLER kits.

    Charlie is correct on his clearance assessment. Remember, you may choose to add catenary down the road, so you want to be ready for it without a headache. Always add a hair more than you think you need to anticipate future needs ! [​IMG]

    Shamus is as usual sound on the curves. You will be pleased with the results, especially if it's something you never considered.

    Woodie, I lived in a town next to Hackensack for a period. Did you know that it's the most densely populated place in the United States, in the most densely populated county in the country? Never been to Boise! As for converting to metric, the great tragedy in Canada was we lost the Imperial Quart!

    I like choosing distant endpoints, Bob. That way, more selection to motive power and running big stuff. OK, so how about "Ozark and Winnipeg"? There's potential for yet another "Old And Weary" route for you!

    George.
  8. Bob Collins

    Bob Collins Active Member

    Joined:
    Feb 2, 2001
    Messages:
    1,023
    Likes Received:
    0
    Now Ozark and Winnipeg has real possibilities!! I don't know what they are, but surely there are some there [​IMG] If you went up that route when I was a kid there were actually some narrow gauge routes in Nebraska you would cross. Since mosr RR in this country are oriented east and west you have the opportunity to cross a LOT of those lines between the Ozarks and Winnipeg.

    Thanks

    Bob
  9. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    Need some info on clearances?
    http://www.nmra.org/standards/s-7.html give clearances for tunnel construction, platform height etc
    http://www.nmra.org/standards/s-8.html give track learances for parrelel track, on most raduiss. and also for dual track. Measurements are from track centres, indsie and outside rail of the curve as well.

    I followed all of these, and got a bit to ahead of myself I think. Tried to sqeeeeeeeze that last minute thought turnout into the layoout. WRONG... stuffed up the curve, (curve radius was less than the turnout radius. RIP! (and that's not Rest in Peace"). NOw I've had to rip up the whole corner to realign it all properly, so the turnout fits in rather than "benda de track, Benda de track" should have Yuri Geller here... He was good at bending spoons, perhaps he bend my track poperly!
    [​IMG]

    TOOT!
  10. George

    George Member

    Joined:
    Jan 2, 2001
    Messages:
    532
    Likes Received:
    0
    Hey Woodie!

    I hope you had not glued down the track as you went along! [​IMG]

    Bob, just think of all the interchange possiblilities you have on a run from Missouri to Manitoba depending on time period. Your primary competitor would be the ICG and KCS.

    Take a look at a map. If you start in Memphis, and track through St. Louis, Des Moines, Minneapolis, Fargo, Grand Forks to Winnipeg, you interchange with;

    ICG,KCS,PRR,NYC,CR,MP,UP,ATSF,C&NW,Soo,CP, CN,GN,BN,L&N....ARE YOU DIZZY YET? And I'm sure I forgot some.

    Guess grain would be the main item shipped? [​IMG]

    Have fun!

    George.



    [This message has been edited by George (edited 05-08-2001).]
  11. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    George.... yep glued it all down and ballast as well as scenic construction... Then decided I needed that extra turnout (to run off the layout, as an extention). Thought I'd get away with it, just snip here, cut there. A large hammer was actually needed. A jackhammer wouldn't have gone astray!

    Motto of the story? "If at first you don't succeed, use a larger hammer!

    TOOT!

    [This message has been edited by Woodie (edited 05-08-2001).]
  12. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    ...... I've now hidden the hammer! Hammers can be so destructive! [​IMG]

    TOOT!
  13. George

    George Member

    Joined:
    Jan 2, 2001
    Messages:
    532
    Likes Received:
    0
    Could you have "spliced" it using a Dremel?

    George.
  14. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    George,

    I could have just spliced it in. I actually did that, however the approaches to the turnout did not match exactly with the radius of the turnout. I have had ongoign problems with the same curver before this. Too sharp a grade on the intial raised track at the furst riser, was causein derailments etc. The problem area I am replacing is the area that I try everything first. So that explains the balls-up.

    TOOT!
  15. George

    George Member

    Joined:
    Jan 2, 2001
    Messages:
    532
    Likes Received:
    0
    Easing into the first riser is always the worst.

    George.
  16. Bob Collins

    Bob Collins Active Member

    Joined:
    Feb 2, 2001
    Messages:
    1,023
    Likes Received:
    0
    Greetings;

    Suddenly I'm seeing discussion about risers and that brings a question to mind. What do you "experts" consider to be the maximum legitimate grade for mainline operations? I know that on a layout like Shamus runs you sometimes think you are asking your equipment to run straight up and down, but what can I expect to be able to do with my layout if, for instance, I have a 4 percent grade (which I don't). Would it need to be downhill only? My layout would allow me to run at least a 100 car train assuming I had the power and traction to pull it. Would a 4 percent grade reduce that capability by say 50% if I used the same power and had the same traction, or would it degrade the capability even more?
  17. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    Bob,

    I have a rise of 80cm in 2 metres. I had to do that, so I could get some track over the other track, and I'm on a small layout (1.2m X 2.4m). That is a 4% grade and that is too steep, for both uphill and downhill. Struggle to the top (that's if I dont get wheel spin first!), then takes off full pelt on the downhill grade. Thats with a load of 4 passenger cars.
    That rise is something I have to live with because of the size of the layout. It also looks a little unrealistic, especially as I was building it. It doesn't look to drastic once the scenery has been built around it.

    TOOT!
  18. Woodie

    Woodie Active Member

    Joined:
    Mar 23, 2001
    Messages:
    2,227
    Likes Received:
    0
    Bob,

    I allow other era/region/country rolling stock to run on mine, however I would not go and purchase any of it. The French TGV would look silly running through the Australian outback. Even though I have a theme, I hove not set out to model a particular real prototype, so I would still call my layout "freelance" as it could be anywhere in the time/location/era of the geographic location I have modelled it on.

    TOOT!
  19. Bob Collins

    Bob Collins Active Member

    Joined:
    Feb 2, 2001
    Messages:
    1,023
    Likes Received:
    0
    Although I haven't touched a piece of scenery yet I am planning to be boring USA midwest. To me that seems to signify that if today I want to run 1920's Milwaukee and tomorrow 1990's UP that is simply up to me. I agree with you that for me to run something like the TEE or TGV would look pretty silly.

    If I have the opportunity a may try to create a 5% slope on my workbench just to see what it looks like.

    As a matter of interest. On what was the old Frisco mainline between Tulsa and St. Louis and is now a BNSF mainline there is a grade that is 12 miles long and comes up 472 feet. If it were all the same grade that would be something like 0.007 if my math is correct. Unfortunately it isn't a steady grade and in the old days they always hooked a pusher on the freights to get them up the hill. I always think of those sorts of things being in the Rocky Mountains out west.

    Do I understand you to be in Australia? We are planning to visit there, particularly the Brisbane area for the Rotary International Convention in June 2003.

    Bob
  20. George

    George Member

    Joined:
    Jan 2, 2001
    Messages:
    532
    Likes Received:
    0
    Bob,

    Stick to a limit of 3-3.3% unless you're building a cog railway.

    I've ridden up a 3% grade and it was like being aboard an airplane struggling to get off the runway. The train I was on had a helper pushing at the back as well. 3% is dreadfully steep in reality, and a runaway is supposedly like being on a rollercoaster.
    I made a steep grade once and I just kept getting the feeling that I was tearing the life off my engines with it. Like Woodie says, the train struggles to the top and then flies down the other side. Just like the real thing, the momentum of the cars pushes the whole rig out of control if you're not on top of it. When you're running 10 passenger cars, or 20-30 freight cars, it gets a bit frightening.

    Yes, I had a derailment, and thank goodness it didn't go over the side, but like Lionel, it all went over onto it's side! One derailment coming off the grade was enough to make me tear it out.

    Now, I let the terrain go up and down and keep the trains level.

    As for freelance, when it's freelanced, almost anything goes I suppose. The joy of a freelanced line situated in the real world is that you can have locomotives from other lines at the junctions, or give them trackage rights over certain stretches. With trackage rights, you can run freight driven by foreign motive power, passenger trains, whatever.

    It's a writer's (modeller's) license with the convenience of running a bridge line.

    Woody, why don't you hook up a switcher to the TGV? Then you can say it's being hauled off to a SCRAPYARD in the outback!!!!! [​IMG] Just thinking of my last trip to France, guys...

    George.

    [This message has been edited by George (edited 05-10-2001).]