Peter's Model Railroading - Modeling Articles

AMI Roadbed

For my third layout, I decided to try the AMI roadbed material. I heard from experienced model railroaders that if they were to do their layout over again, they would choose AMI Roadbed.

Update: It is my understanding that AMI Roadbed is out of business. However, there is similar material available, for example "putty tape". Also 3M makes "Scotchfil", which looks an awful lot like the AMI Roadbed.

For laying flextrack, this is (in my opinion) the best method for laying track. It allows some freedom and flexibility in laying track, and allows for creating a very prototypical roadbed profile (profile is needed to allow rain water to run off the track area quickly and into the ditches). Long-time proponents of this material are the famous Reid Brothers. Allen Keller's video of the Reid Brother's layout has a segment where they describe how to install the material.

AMI Roadbed is a rubber-like material. It does not smell, nor is it toxic. It looks like a tar-like material. It is very sticky to itself and mildly sticky to other materials. One box contains one roll of 30 feet of the material.

Non-permanent Installation
If you want to easily remove the AMI Roadbed material in the future, just lay it out on the plywood or other material subroadbed. Make sure the plywood (or other) surface is clean, or otherwise the AMI Roadbed will stick to the dust and not the base. Use the strip of paper that separates one layer of the material from the other in the roll to press the AMI Roadbed firmly onto the subroadbed. I use a J-roller for that. Make sure to keep the roller parallel to the subroadbed otherwise the AMI Roadbed will not provide a level surface for the track (unless, of course, that is what you want).

Permanent Installation
The most effective method I have found is to use "Liquid Nails for Foamboard". Spread it thinly over the area where the AMI Roadbed will be installed, and place the Roadbed on it. Just finger-pressing it into place is sufficient. Using a roller won't work because the Roadbed will move around on the glue.

Attaching Flextrack

For my third layout I laid out my track (Micro Engineering code 55 unweathered) on the AMI Roadbed. The track is just pushed down a bit, but not a whole lot. I used to use the J-roller to really work the track into the Roadbed, but the track had a tendency to get out of level due to the inevitable uneven pressure excerted on the roller. Just press the track down a bit enough to make it stay. Then rely on ballast to hold the track down to the AMI Roadbed.

After laying the track, I shape the outside edge of the AMI Roadbed. At first I used a flat-head screwdriver (gleaned this technique from the Reid brothers as covered by Allen Keller's video tape), but now I simply cut it with a #2 Exacto blade. The blade is flexible and makes it easy to shape the roadbed to fit the track. You can rest your hand on the track, which makes it very easy to stay close to the outside edge of the ties.