Cookie cutter serves a few purposes. It’s design is to basically eliminate the flat table top look. You cut the plywood a bit wider than the roadbed. The roadbed is supported by risers with cleats. This allows elevation changes in the track. Seeing the track is higher than the benchwork it allows the modeler to vary the terrain. HO guys tend to use it because the scenic elements is important to the design of the layout. Where there is no track. You fill the open space with plaster cloth or foam.
It’s not used as much in the O Gauge world. Most refer to benchwork as tables. The goal for many is to get as much track as they can in a given space and it’s just easier to go this route with a flat layout. Nothing wrong with this approach if you want to run multiple trains in a given space.
Another alternative is spline roadbed. Can save you some money if you have access to a table saw and woodworking equipment as no wood is wasted.
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