How I Built My Granite Block Retaining Wall
In this particular situation on my layout I have the roadway going under the train tracks. It goes below normal ground level and results in a variety of places where the earth needs to be held back. My implementation of the curved shapes and the different angles was on purpose - I wanted a final product that was unique, eye-catching, and prompted comments such as "Wow! How did you do that?"
Making the cuts and forming the earth was the easy part. Figuring out how I was going to make and build the walls was the hard part. While working on other sections of my layout I would mull over different ideas none of which stuck with me except for one - build temporary frames and pour plaster in place - and even that one did not excite me all that much.
Then one day while roaming through Home Depot's flooring section I stopped to look at floor tiles. What I picked up was a 1'x1' linoleum piece. What caught my eye was the rough texture of the edge of it. Then the light bulb came on, "Hey! In N-Scale world that looks like stone. If I had a bunch of these cut into little blocks and stacked up it would look like a granite block wall!" BINGO!!! That was it!!! Building a wall in this manner would let me build to any shape, height, or curve I wanted to.
They had several colors to choose from. The ones I was most interested in were gray, tan, and a darker tan. I chose the tan because the gray was too dark and I figured the tan color would be closer to a faded gray look than the actual gray itself. In hindsight, I think I would have been better off with the gray but, none-the-less, I am happy with my selection (and isn't that what this hobby is all about?). The tile was about 1/8" thick and I bought 2 of them.
After some trial and error I determined the following method to work best for making my blocks. (Tip: Linoleum is quite soft and easy to bend and this softness is affected by temperature. A piece which has been out in the cold will be too brittle and will break too soon while one which has been sitting in the sun will be too soft and will not break in a desired straight vertical line. So, work with a piece that is acclimated to a comfortable living environment temperature and not one that you went and got out of the cold unheated garage in the dead of winter.)
At this point I stopped work on the first wall and started the second one. I held back on taking the first wall all of the way to the end because I was not sure how it would come together with the other walls.
Then I started on the 3rd wall - the one that goes under the bridge. Following is a shot of it being built. Here is it lying front-down instead of up against the vertical board. I decided to try something different in my construction method. Instead of placing a dot of glue onto the block and putting it in place I placed the block in place and then put a drop of glue at the joints replying on capillary action to suck the glue in. It worked OK and is an acceptable method when wedging bocks between others as in the picture below but when building one on top of another its better to put the glue on the block first.
So now these 3 walls were coming together. This happened a little at a time, some work on one wall and then another, such that they all gradually come together as 1 unit. The following pictures show the 2 bottom walls beginning to be 'woven' together as the top wall comes closer to being part of the completed section.
As the following pictures show, I have the first curved wall built and am in the process of weaving it into the wall under the bridge. For this wall, I built it upside-down. Why? Because the top is the longest part and, by placing it upside-down, I can easily add blocks to a flat surface instead of an angled one. For example, in the following picture you can see along the bottom of the curved piece that I need to add more blocks to bring the wall down some more. I did so by turning the piece upside-down and gluing some blocks in place. Simple as that.
As it is, I am able to tilt and slide the entire structure (minus the first wall I started building) out from its place. In the following pictures I am cutting and wedging in corner blocks where the walls come together.
At this point I have done all I can do on the wall structure which would require me to remove it from the layout so it is time to make it permanent and start building the first wall into it.
Almost got it done.
Looks like I can add about 2 more rows of blocks for the part directly under the bridge.
Rounding 3rd base here. Finally around the corner and starting to build up. These last couple of rows were built in place. The only thing I had to watch for was making sure I kept the front of the wall straight and true.
The linoleum tiles have a swirly pattern made into them and, even at the small size of these blocks, that pattern was apparent and undesirable. My solution was to rough up the tile with sandpaper and make special cap-stone blocks from that. Below shows the sanded tile and the final top row of stones being glued in place. All of the walls, except those directly under the bridge, got this final row. It turned out OK I guess. If I were to do it again I would sand it even more.
To secure the walls in place I crammed scrap pieces of foam behind them and drizzled glue. Once that was dry it was time to build the ground. I used Sculptamold for my ground form.
Then, once dry, I painted Sculptamold brown. Here are some pictures as it stands now. I will add more as time goes on.