Separation of tracks

[bamawhiteman]

For an O gauge layout what would be the minimum center to center distance for parallel tracks to not have danger of contact?

[lionelsoni]

The maximum width of American trains is 128 inches, which is 2 2/3 inches.  So, unless your models are larger than scale, that would be the absolute minimum for straight track.  On curves, all bets are off, since it depends on the radius and the geometry of the models.

[challenger3980]

  As Bob said, this will depend A LOT on your curve diameters and the longest and widest cars and/or locomotives that you will be running(now, AND in the Future) In the pics below, the outside track is 054 curves, the second track in is 042, with 054 transitions, track 3 is 042 and track 4 is 031 curves. These tracks were laid using short fitter pieces in the sides and ends to maintain a minimum of 5.5" separation at any point.

 As seen in the bottom pic, my normal roster in use included a Lionel LionMaster Challenger on track 1, pulling a set of K Line 18" scale size Heavyweights. On track 2 is a Lionmaster Big Boy pulling freight in the opposite direction. With 054 and 042 curves, and this combination of equippment, I would not want to get even SCALE size fingers between the passenger cars and the cab overhang of the Big Boy on the curves. Fortunately I laid the curves even more accurately than I had expected to need to, even 1/8" of variance would have meant bad things happening.

 

 

Doug

[phillyreading]

Like Bob N. mentioned for straights. Curved tracks can be highly irregular for any set distance between rails, steam engines especially need some different clearances. A combination 4-6-6-4 or UP Big Boy would probally need the widest clearance due to the articulated steam chests on that model, also need to measure the front end swing out and the rear cab's roof swing or hang-over, sometimes a tender's side steps will interfere with a bridge post on a bridge or trestle.

I run a lot of steam engines and have found that they usually need more distance than the diesel engines do. On my layout the Reading T-1(4-8-4 Northern, MTH PS-2) has a cab roof hangover issue that none of my other steam engines have and this causes me the most problems with clearances. While an engine may run on 042 it will probally work better on 054 or 072 and have less hang-over issues. Unless you have a large layout or have a large distance between rails is it good not to run scale steam engines.

Lee F.

[RockIsland52]

Doug.....sweet!  If I attempted to commandeer that much space under the her Christmas tree, my wife would have me buried in a shallow grave in the back yard.

Jack.

[challenger3980]

Howdy Jack,

  I was SINGLE, the couple of years that I used that platform under the  Tree, I needed to have the track secured solidly, because even the smaller locomotives were causing the track to move when they entered the curves, even with MTH's rubber feet in the Realtrax, it was still moving on the Hardwood floor.

  I got Married last May, so the platform went unused last Christmas. She said that she needed more ROOM under the Tree than what the platform allowed. OKAY!!, so when she wasn't home one night, 2 loops of 072, and a loop of 054 Realtrax went down under the Tree, just directly on the carpet, no platform. She was a Little Surprised, when she got home, but my 16 year old Step-Son thought it was Cool, Especially when we got the Scale size Steamers running.

  Silly Gal thinks that I have ENOUGH TRAINS, Ha Ha Ha, I still Love Her any way, and with things slow at work, she MIGHT be right, FOR NOW!!

Doug

[11th Street]

It's all about the overhang in the turns.

For 21" passangers/072 minimum type locomotives and 072-080-088 curves I use 6" on center.  The straights are a matter of aesthetics.

Be aware the same goes for trackside scenery. 

Your results may vary, so there is no substitute for a real world test with your own equipment/layout.

 

[traindaddy1]

to the Forum:  Without getting into 'technical' exactness, I would, having learned the "hard way", use the old "try-it-out" technique. As mentioned, the curves are the key. 

My suggestion: Lay out your track (don't nail it down) the way you would like to see it.  Then, run your largest (longest) consists, side-by-side on the tracks.  Allow for a little extra room (you may be buying larger stuff later) and don't forget the scenery along the tracks, especially if the items are higher that the track height. (You don't want to have everything set and then find the train running into a shrub, tree or building). 

Also, consider your accessories.  Examples: Are your trains approaching a station on one side or are they pulling in on both sides of the platform?  Do you have a loading or dumping set that will take up more room along one of the tracks?

I know, I know, I wrote a lot that probably doesn't answer your intitial question but just some thoughts.

Good luck and keep posting questions and comments.

 

[richhotrain]

challenger3980

  As Bob said, this will depend A LOT on your curve diameters and the longest and widest cars and/or locomotives that you will be running(now, AND in the Future) In the pics below, the outside track is 054 curves, the second track in is 042, with 054 transitions, track 3 is 042 and track 4 is 031 curves. These tracks were laid using short fitter pieces in the sides and ends to maintain a minimum of 5.5" separation at any point.

 As seen in the bottom pic, my normal roster in use included a Lionel LionMaster Challenger on track 1, pulling a set of K Line 18" scale size Heavyweights. On track 2 is a Lionmaster Big Boy pulling freight in the opposite direction. With 054 and 042 curves, and this combination of equippment, I would not want to get even SCALE size fingers between the passenger cars and the cab overhang of the Big Boy on the curves. Fortunately I laid the curves even more accurately than I had expected to need to, even 1/8" of variance would have meant bad things happening.

Doug

Doug,

Looks great.  What are the dimensions of the outermost track?

Rich

[TRAINCAT]

For our modular layout and my own as well, I use 4.5 inches between center rails.

Roger

[Buckeye Riveter]

One thing I have encountered is that my steam locomotive when running backwards overhangs more than when it is running forward.  The corner of the cab roof will hit the tunnel portal in reverse and never touch it when running forward. 

[challenger3980]

Rich,

  The overall dimensions of the platform are 5.5'x8', and the outermost track is 054 curves with straights in the end to maintain 5.5" seperation from the next track, which is 042, with 054 transitions. I built this platform with 054 curves on the outside track specifically for my Lionel Union Pacific FEF-3's, which according to the box, they would run on 054 curves. Wrong, the 5 rigid axles on the tender wont handle 054 Realtrax, the last axle derails just after entering the curve.

 The  FEF-3's were my first scale size locomotives, after that, I pretty much had to accept that I would have to work with 072 curves in the future, as the FEF-3's were "Must Haves" in my collection. That opened the door to many other "Would Really Like to Haves", and I have now been bitten by the Scale Size bug in a serious way.

  Here are some pics from the other side of the platform. I put casters on it, so I could decorate the Tree easily, then roll the whole thing into the corner by the window. I used  bannana plugs in a project box to make connecting the transformers quick and easy. Speaking of Quick and Easy, those rounded corners were anything but Q&E, but I did like the way they came out though.

Doug