And here... we... go!
Last part of this tutorial and my construction of the game table for Historicon is finishing the river. There are lots of different methods and a quick Google search will turn up all of them. The simplest method is probably to brush on gloss varnish, but it requires multiple coats to get good results. My favorite medium is a 'pour on' varnish that is like adding 60 coats in one shot!
There are many different brands available at hardware stores (mine seems to carry a different one every year) and there are commercially available 'water effects' for modelers that work much the same. They are all two-part epoxies that are designed to be mixed and poured onto you surface - the one I used this time around was from Parks. If you use one of these kind of products just follow the directions that come with it. The main thing you want to do is make sure the two parts are mixed thoroughly or the mixture can dry tacky.
To keep our super-cool pour on river from pouring right off the boards, we have to dam the ends. I put a bead of hot glue on the edge of the board around the end of each river and slapped a piece of plasticard to cap off the river. It will form a waterproof seal and after the river dries, you will be able to pop these off and peel away the hot glue.
Now comes the cool part! After mixing the epoxy, all you have to do is pour the mixture onto the river bed. Avoid pouring directly over rocks and reeds. This stuff will flow into nooks and crannies and you can use an old brush to pull it into any area that it misses. At the early stage, you won't harm the finish by dragging the brush through it - after a minute, you won't be able to tell you touched it.
That's it! Finished. I'll have more pics of the completed boards in the next week or so, including the whole table if I can manage find room to set it up and the loose terrain that will finish off the table for the Napoleonic scenario. Hopefully this has helped anyone who is contemplating building their own terrain. If there are any questions involving techniques, materials, or anything else feel free to post them here or contact me at email@example.com.