Garden Railway Test Track
One of the recommendations that I’ve read is that building a “test track” to run the occasional train on provides a nice way to get some entertainment while the main railroad is under construction. So I am going to do just that, hopefully finishing it by next spring. I picked an area of the yard away from the initial phase of construction, so that there is no interference while I get phase 1 of the railway built. (See Rio Grande Southern Oregon)
In the process, I’m going to experiment with several different roadbed and scenery building techniques. The test track will also be a place where I can install some of the bridges destined for the complete railway. That way, I will have fewer “place-holder” boards spanning gaps while waiting for bridge construction.
The roadbed techniques will be:
- Recycled closed cell foam (Styrofoam) to build raised roadbed;
- Conventional HDPE 1×2 ladder roadbed;
- HDPE 1/8″ x 3″ plastic with cross-pieces, filled with a base of ballast and filled with polyurethane foam (such as Great Stuff).
The scenery techniques will be:
- Hypertufa tin-foil castings and direct application on hardware cloth with wooden supports;
- A hard-shell method using hypertufa and burlap over a recycled yard-sign plastic grid similar to what small-scale indoor modelers would build with hydrocal;
- Obviously rocks, dirt and plants.
Track Plan
The track will be a simple oval, with 2.5% grades and five bridges (which are all destined for the finished garden railway.) The overall size will be about 28 x 14 feet, given that scenery and bridge widths will add to the footprint somewhat.
Roadbed Construction – Expanded Foam
Here are construction photos of the tallest section using recycled foam (from an old hot-tub cover). The foam will be covered with hypertufa scenery to model the rocky Colorado terrain that this bridge helped traverse.
The first section installed. I used landscape foam designed for gluing rocks in place around ponds to hold everything together.
A string was set to the height of the track between two posts, with intermediate posts “glued” in a sandwich between two chunks of foam.
A heavy duty “hot knife” from Micro-Mark made quick work of the foam as I trimmed the pieces to the correct height.
Here is a section ready for trimming to fit Bridge 46-C – a 70″ long Howe Deck Truss bridge. This bridge is the largest in the test track, and the tallest.
Installing the Bridge
I used the hot knife to trim the foam to the appropriate contour. The bridge rests on cuts in the “rock”. The level is a 2.5% grade device, with a 1/2″ block at 20″ from one end of the level.
The bridge needs to be level side-to-side as well as at the correct grade.
Scenery
For constructing scenery, I’m trying a couple of techniques. First, I’m going to take a page from small-scale indoor modeling by using the “hard shell” technique. But, with recycled plastic covered with burlap soaked in cement. (Actually hyper-tufa.)
The burlap absorbed a LOT of liquid, making the cement thicker with each piece. I’m going to make the next mixture really soupy, and leave out the peat moss. I may use more vermiculite to add bulk without adding weight.
I stopped after covering most of the top, as additional pieces of burlap on the steep lower parts were starting to pull down everything. Once it cures, I’ll be able to add the rest.
I noticed a downside to this: the plastic doesn’t allow the cement to adhere, so the result will be largely a shell over the plastic. That may or may not be important. I’ll use hardware cloth for the next area.