After reading numerous posts about these subject, I don’t see any that answer my questions. Here they are:
Is it a big deal that I carved the river about an inch deep and it isn’t completely flat? Most rivers in real like aren’t perfectly flat either. Besides, I figure to fill up the water close to the top but leaving some depth for banks on either side.
Should I use WS plaster cloth on the foam to seal up the river before painting it or use gloss medium (mod podge)?
What types of brushes to use for painting the river (foam or bristle)?
The “water” you use, if you use a “poured” medium like Envirotex, will level itself out. No problem. If, on the other hand, you just add a gloss medium over the unlevel streambed, your "water’ will be sitting on an angle, which never happens in nature.
Plaster cloth is fine.
Doesn’t matter. Either will do. You might try spraying the colors on to blend them better. Even spray cans, used carefully, will do well here.
Here are a few photos of a pond I did recently. I basically did what you’re suggesting. First, I gouged out a basin about 3/4 of an inch deep in the pink foam. This resulted in an uneven surface which didn’t look like the bottom of a pond at all. So, I put down a layer of plaster cloth:
This gave me the contoured stream bottom I was looking for. I used a skim coat of Gypsolite and cheap acrylic paints to coat the bottom. I used black and dark blue where I wanted the water to appear deeper, and faded it up with greens and light browns towards the shoreline. I also placed rock castings, talus and plain old sand on the surface. All of this was glued down, so it wouldn’t float in the Envirotex.
Then I poured the Envirotex. I did several pours here. The first only filled the deepest sections. I tinted that “water” with a bit of black and blue acrylic paint. The next pour was done with some green tint, and then the later pours with less of the green. The tinting gives more apparant depth, and makes the deeper water less opaque, adding to the illusion. It only takes a couple of drops of paint to an ounce of the Envirotex to get this effect.
Last, I added the surface details. Envirotex will creep up the sides of your waterway. Where it climbed up the stone bridge, I concealed it with the tall grass. On the shore, I added a bit more sand and rock. The waterfowl (from Preiser) are a focal point which draws the eye away from any other little imperfections.
Plaster cloth on foam will work very well. Just make sure you go over the wet cloth with your fingers to completely seal the plaster into a smooth coat. After it’s dry (about two days) you can go in and paint it with almost any kind of brush you prefer. I have a portion of my model railroad where two rivers come in and form Bullard’s Bar reservoir in the Sierra Nevada mountains, and it was all laid on foam with plaster cloth. I used various shades of acrylic paint going from a sandy color on the shore to a deep blue-black in the middle (this is a deep reservoir) and then poured WS ‘water’ on in three 1/8" coats, waiting about 48 hours between coats. Environtex will work just as well, if not better, from what I’ve seen. Just remember to put in any shoreline or ‘underwater’ details you want (boulders, etc) before you ‘pour’ the water. Also, if your lake ends near the front of your layout, make sure that you ‘dam’ it with something–I used masking tape which worked fairly well.
But in short, yes, plaster cloth and foam can be used to create both rivers and lakes rather well, IMO. If it helps, here’s a partial shot of Bullard’s Bar reservoir.
