Short Line Roadbed


KatzDad

New Member
I'm approaching the point where I can start laying down roadbed on the HO scale Chumani Gap RR rebuild. The base is CS foam board. Standard HO roadbed material - cork or foam - is too tall at 5mm to be prototypical for a short line. Has anyone used N scale roadbed for HO track? The N scale 3.5mm high is closer to correct height for the mainline but appears to be too narrow on top, leaving the ends of the ties hanging in the air. Cascade, the former homasote roadbed manufacturer, is out of business and I really don't want to make my own roadbed from sheet homasote.
 
First, I use N scale roadbed on my HO scale layout, along with HO scale. I use it on passing sidings, while I use HO scale on the main lines. There are two ways to go about this. The way that I do it is to just use it as is, not even splitting it and let the ties hang over the ends, barely. I then fill that outside space in with ballast using an old broad paintbrush to shape it into an acceptable contour. The other method is to split it like HO scale and leave a space down the center. That space can be filled with caulk, dry wall patching paste, sawdust or other material before laying track. You could also lay the track and let the ballast fill the void. I have done it both ways but I like the first method better because it's easier for me. Both will use more ballast if $$$ are a concern.
Next, note that not all short lines have lower profiles. Many of them came to be when class 1 railroads sold off excess trackage/right of way, that already had heavy main line on it. I see from your introductory post that you are modeling an Appalachian short line, so that may not be acceptable to you.
Here is an example of a section under construction from 2016.
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Here's a semi-completed section from elsewhere that has already been ballasted. The track with the light colored (new) ballast is the main on HO scale roadbed, while the track to the left is the passing siding. All other tracks are industry spurs using cereal box cardboard as roadbed.
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Happy modeling.
 
Thanks, Willie! You're correct about the CGRR not using previously laid Class 1 trackage, so the standard 5mm high roadbed, while useable as a last resort, wouldn't be accurate. I'll try both ideas - splitting and filling the gap, and using ballast to sculpt the sides - on a test piece and see which works best for me.
 
I don't believe you are correct in assuming that a short line also needs short ballast skirts. Ballast serves the same purposes wherever it is found, so the 'size' of the railroad is immaterial. What matters is floatation and drainage at grade, and that is the same in Timbuktu as it is in Lahore, India.
 
I don't believe you are correct in assuming that a short line also needs short ballast skirts. Ballast serves the same purposes wherever it is found, so the 'size' of the railroad is immaterial. What matters is floatation and drainage at grade, and that is the same in Timbuktu as it is in Lahore, India.
I understand that the class/size of the using road isn't the prime determinant of how roadbeds are constructed and that drainage is critical in determining how track is ballasted. However, finances certainly can be/was a determining factor, as well as speed and weight/number of trains running over the tracks. A look through "Mixed Train Daily" by Lucius Beebe shows - and describes - many short lines from different regions of the country that were operating after WWII and had roadbeds that were far less substantial than class 1 roads. The backstory I created for the CGRR is a small operation begun at the end of the 19th century to serve communities not reached by the ACL, SAL, SR or C&O; a typical small operation with limited financial resources, running a limited number of relatively slow, short trains over a short length of track. The CGRR isn't running on track laid directly on the ground due to the weather the region faces (drainage and floatation), but it didn't have the financial means to construct a class 1 roadbed. Hence my desire to keep the roadbed for the CGRR below that of a class 1 road while maintaining a semblance of realism by having its tracks ballasted in a manner that would be at least minimally efficient but affordable to a line with limited financial means for roadbed construction and maintenance.
 
I may have found my answer. I tried a test section of track on N scale roadbed, laid as santafewillie suggested - split the roadbed and filled the gap with spackling - and it would certainly fill the bill. However, while checking further on the 'net I came across a Rapido product that is designed as branch line roadbed. Closed cell foam, 1 7/8" wide at the bottom, 1 9/16" top width and only 2mm high. The height is actually a mm lower than N scale roadbed (any of y'all old enough to remember a cigarette commercial that touted the product being "a silly millimeter longer"?) and the width means no splitting and filling the gap. Have ordered some and will report on the result when it arrives sometime next week.
 
Will do, flyboy. Due to the current craziness the vendor is a little slow with filling/shipping orders but expect to have the roadbed before the end of next week.
 
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I've found the solution to my quest for a roadbed to use for a short line operation. The attached photos - not professional, I know, but I think they suffice for illustration - show 3 different options; cork HO scale, foam N scale that's been split to 1 1/2" width at the base and the gap filled in per santafewillie's suggestion, and the Rapido branchline foam with some old & scrap track laid on top of each to show perspective. The Rapido has the same base dimension as the cork but is 2mm high as opposed to 5mm for the cork and 3mm for the N scale. The Rapido foam feels as good as the Woodland Scenics foam, and since it's a Rapido product I am confident the quality is good and the roadbed material will last a long time.
 
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