Most of what I'm modeling, Illinois and Iowa is flat. My layout sections are only 18" to 24" deep, so the challenge is to work in subtle elevation changes; especially with regard to track. So I've been dropping some sidings 1/8" or 1/4", within two to three scale feet. The surface of the layout is rigid foam insulation on masonite, so I can't lower or raise track sections as you would with a cookie cutter type of construction with plywood. Most of the track is on 1/4" Homabed, homasote roadbed. My first solution to lowering a siding was to pave a ramp with scultptamold. While it can work, it's not the most accurate method. One night while feeding the woodstove with some cedar shingle scraps, I had my answer, even though it was quickly engulfed in flames...fortunately I have a left over box of cedar shingles in the garage.Even if I didn't have the shingles, a wood shim would also work as a nice, subtle grade changer. It's quick and easy. However, I wouldn't recommend it for mainline grade changes, but for my purposes it works just fine. The shingle can be split by hand for width, and scored with a utility knife for length. In some cases you can even work in a bevel and/or curve where needed. They could also be used, I suspect, for automobile roads in some way.
As more of these mild grade changes are added, the landscape appears more natural. While it's barely noticeable in the photo above, in person it's more obvious, especially when a local freight takes a small dive or crawls up the incline. It's a tiny drama in the scheme of railroading, but still dramatic...and when you're not modeling large mountains or canyons, you take what you can get.
