This layout resides over my workbench at a height of about 55” from floor to railhead. I wanted all 20’ linear feet of the workbench to be accessible by a rolling chair, as I have different stations along it - painting, electronics, assembly and build area, machining, parts storage,…etc.. This meant no legs to impeded my lateral movement. Additionally, I didn’t want any vertical supports between the layout and the workbench to obstruct the work space. The bench and the layout would have to be cantilevered off the wall.
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| You can see the framing for the layout and workbench on the left. They are both supported by the same vertical “legs” spaced about 4’ apart. The radius arch horizontals don’t interfere with legs, while moving back and forth, and also don’t interfere with the work area. They are actually handy for storing clamps. |
As you can see from the photo, there are plywood stringers, with a L front assembly to strengthen the edge. Everything is made from 3/4” maple plywood. The work bench has steel Unistrut stringers for sturdy support without sacrificing leg room.
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| The “sandwich” Unfortunately the seam fell just at the end of a piece of roadbed and the chunk of homasote on the right is only a 1” triangle. |
The layout surface is a sandwich of 3/4” foam core maple plywood, two layers of 1” foam, and 1/2” homasote. The whole thing is an effort to keep the weight down on the layout. Everything put together, including the homasote was probably around 30-40 pounds.
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| Foam inlay cutouts for homasote roadbed. |
The maple foam core plywood was secured to the framing with washer head cabinet screws from underneath. While it would have been more economical from a material standpoint to utilize full sheets of plywood and foam, I cut all the layers in three equal length sections. The idea is that someday, it would be easy to remove the sections, by just cutting the rail at the seams between. Since this is as much a diorama as a train layout, I sort of intend on changing it in the future and building an entirely different scene.
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| Homasote roadbed pressed into foam |
Since the layout was drawn full scale in CAD, I used this and a CAM program, to create cut files for a CNC machine, and everything was cut out on that for accuracy. If I was using flex track, I could have attached directly to the foam, but since I’m hand laying the track, and based on experience doing this as a teenager, Homasote is an excellent base for this, and holds the spikes well. Again, with keeping the weight down, I figured on only placing the Homasote exactly where I needed it. Fortunately my CAM program has an inlay feature. This feature generates the cut file for the pocket in the foam, and the file that cuts out the Homasote. It’s actually more complex than it seems. Since the CNC machine cuts with a round bit (1/4” in this case) the cut in the foam would leave a 1/8” radius on the inside corners, but this same corner on the Homasote, would be an outside corner, and would be cut sharp. The program figures all this out, so you get a perfect fit. I programmed in a 0.020 allowance on the cut, and everything fit perfect but I had to tap them in slightly. Doing it again, I would have gone with 0.030. I could have set this pocket to any depth, but since I’m modeling well used industrial track, I wanted the bed almost flush with the surface. Another nice feature of using the CNC - I used a v shaped bit to cut a barely visible centerline in the roadbed.
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