Clearance from rail head to bridge bottom???

Dave; I just measured a variety of my scale diesels and steam; most would clear 4&1/8" from the railhead.

Where you will run into trouble is some of the scale cars which are taller than most engines. I know the Lionel Lift Bridge will take anything I threw at mine; the Lionel swing bridge and bascule bridge will not take most of the taller scale cars out there.

I think one of my taller cars was the MTH Schnabel car + various double-stacks.

Dave;

In general, I agree with D&H 65's comments - I checked my Vision Line Big Boy and it is app. 4 1/4" off the railhead (I am using Lionel Fastrack). I have some Altas double stacks, and they come in around 5 1/2" when double stacked. Two caveats...  beware of anything with pantographs - if I remember correctly, they come in at app. 6 - 6 1/2". And when it comes to the 213 lift bridge (one of my favorite accessories), the clearance under the bridge is app. 5 1/4", BUT, as the venerable Leapinlarry advised me when I started building my layout, the clearance ON the bridge is only app. 4 1/4". My scale engines just fit, but no pantographs, and single stacks only.

Dave two things to consider:

1. The height from the rail top to the bridge bottom should be enough to clear a Husky double stack.  Even if you dont have them now, you may want them in the future or quite possibly a guest runner may have them. As a rule consider 7" for vertical clearance.

2. As you plan  on running a big boy or other articulated engines be cognizant of the overhang when these large engines are on and coming off turns, even wider than 072. You will need some lateral clearance. Positions any track-side structures away from the curve giving these engines enough track to straighten them selves out.

Good luck with your new RR and psot progress pictures when commence the work

Steve 

The Lionel book "Model Railroading: from the 1940's suggested 6" vertical clearance.  Don't forget things like crane cars and pantographs.

Dave,

Following Steve's suggestions above would definitely keep you out of trouble. I don't run "Double Stacks" so I have to worry about anything that tall,

NMRA Std S7 Clearances, dated Feb 2012 Table 3 ("Modern") recommends 5 3/4" clearance height. I would assume they mean above rail head.

I personally run "Classic era 1920-1968" and have tried to use the 5 3/4" Dim.

The standard covers all scales and show "templates" for various clearances.         

Complete standards can be found on  their web site at www.nmra.org.

Gerry

I use a minimum of 7".

Donald

D&H 65 posted:

the Lionel swing bridge and bascule bridge will not take most of the taller scale cars out there.

There was a modification posted some time ago, where someone added brass extrusions between the bridge base and truss/tower assemblies to increase the railhead clearance to allow bigger cars to use the bridges.

I'm a postwar guy only; I gauged my clearances using a vista dome car.  I recalibrated when I remembered the 3376 Giraffe car, which is slightly taller.  Being a postwar guy, I don't know about double-stacks.

As someone else mentioned, you should also take out your GG-1 and/or Rectifier and measure them with the pantographs up, if you plan on running them that way.  That would seem to be the max clearance you'd need.  Either that, or run those items with the pantographs down or on tracks that don't go under your underpasses.

HTH.

Steven J. Serenska

Dave I would make sure to go with minimum of 6 1/2. That way just in case you can run anything under it. Or if any manufacturer comes out with something higher. Better to do the right height now then have to go back and redo later.............Paul

Don't forget the Lionel Legacy 4-8-4 Santa Fe Northern with Lincoln hat smoke stack! 

I have gone to 10 inches between levels.  While the GG1 with operating pans needs less than 7 inches, the extra space permits me to get to a derailment without too much difficulty.  I have yards on the first level (two Ross 4 ways) and the extra space permits me to get in and fix issues.

The tallest engine I have seen is the Milwaukee Bi-Polar  

Where I worked when on the railroad, was the River Rouge drawbridge,  it was 22 and 1/2 feet of clearance under the bridge.  That would equate to 5 and 1/2 inches of space for trains...

Marty

You can do 6" if you dont have anything with Pantographs. If you have pantographs, make that number 7.5".

In the FWIW category...

My revelation in this department was that the tallest piece(s) of rolling stock in my inventory were the RailKing auto stack cars....having 4 die cast autos/trucks on two levels.  I had accumulated quite an assortment of these, thinking they'd be fun to string together in a long train.

However....

They wouldn't clear tunnel portals, lift/bascule bridge girders, and most of the upper level baseboards that I had already built into the layout.   Yep, that MTH full dome car was NOT the criteria I thought it was for this issue.

Ended up selling off all the RK auto cars.   Much easier than dealing with all the other clearance issues.  Don't have a RK auto car left to give you a measurement.  Just be forewarned.  Wish I had been!!  

Continuing student at the School of Hard Knocks, I remain...

KD

A quick Google search shows Michigan DOT requirements to be 22' 6" (= 5.626"), CSX requirements 23' (=5.75") and UP requirements 23' 4" (=5.833") so 6" would be good.

Link to the Union Pacific Technical Specifications for Construction of Industrial Tracks, which has a lot of information.

Alex