RRCraftsman - Cork Roadbed
General
RRCraftsman cork roadbed is made from high-quality natural cork and is available in rolls, beveled strips, sheets, and pads in 3 or 6mm thicknesses to fit N, HO, S, and O scales. Rolls are somewhat unique as they allow long, flowing stretches of roadbed to be created.
You should unbox the cork and place it in your layout room for at least 24-hours prior to installing to allow it to acclimate to the temperature and humidity in the room. For rolls – remove the pin that secures the end and run your finger through the coils to help it “relax” – this will make it easier to lay flat.
If the cork is dry, which can often occur during the winter months, simply rehydrate it by spraying it with water or covering it with a damp towel. Never “soak” your cork! This can cause it to absorb and retain moisture that can affect adhering to your base board.
We recommend using a good quality wood glue, such as TiteBond I, to secure the cork to your base – either plywood, wood spline, or XPS foam. Apply a thin layer to the surface and press the cork securely into the glue, then secure with T-pins and/or weights. Wood glue will give you about 10 minutes of working time to fine-tune the position and will set up in about an hour, with full cure in 24-hours. Lay one side of cork first, aligning it to the track centerline. Work in sections 6 to 8 feet long, pinning or weighting before continuing. Once the glue on the first strip sets, apply glue to the base for the next strip and to the side of the first strip. It’s always best to overlap your joints by at least 6-8” to maintain a smooth flow. Dampen the cork if you are creating especially tight curves!
Rolls
Cork rolls are unique – they represent half of the roadbed in HO, S, and O scales. Lay one side, then the other. Either use one roll for each half of the roadbed or two rolls side by side for faster installation or longer unbroken lines. For N scale, a single roll supports the full width of the track!
Do not cut or sand the edges! The rolls are exactly the width of the track bed – about 6 scale inches extra on each side of the ties as a bed shoulder. Proper installation requires adding material along the shoulder by applying a bead of caulk. We recommend DAP brand Alex Painters Caulk (white) or Dynaflex Ultra, which is available in colors closely matching the cork material. The advantage of caulk is that it provides subtle, natural variations in the width and angle of the ballast profile.
Bevel Strips
These strips are pre-beveled to provide a consistent 45-degree ballast profile. No additional work is required after gluing the cork to your base. To avoid obvious kinks, offset the left and right joints by 12-18 inches.
Turnout Pads
These pads are designed to support a crossover between two parallel tracks, eliminating the need to cut and fit roadbed strips. The pad can be trimmed if your parallel track spacing is narrower than usual. The pad replaces the inner roadbed strips. You can trim the pad at an angle to follow the track, using caulk to set the ballast profile.
Ballast
Use your favorite ballast media. I personally use Walnut Shell Blast Media that I wash with thinned paint to the desired color. Blast Media is available in specific grades that effectively represent rocks from 2.2 to 3.8 scale inches. Other forms of crushed walnut used for pet birds will not be as regulated and uniform in size.
Spray the track/roadbed with a mixture of water and either alcohol or a few drops of dish detergent (“wet water”), then sprinkle the ballast in place. Use a large, soft brush to distribute it, keeping ballast off the ties. Spray again with the Wet Water, then apply the adhesive – thinned white glue or matte medium, again with a small amount of alcohol or dish detergent. The alcohol or dish detergent breaks the surface tension of the water and prevents the ballast from “beading up” or “floating away”. You need to thoroughly soak the ballast with the glue mixture. Be sure to clean the top and inside of the rails with a Bright Boy or similar product to remove any glue residue.