Dear Friends
I'm about to cut out kind of a large pond at the base of a large mountain on my son's model railroad. My question is about how I should proceed. I don't know whether to use a router and grind out a certain depth of foam insulation, or to cut out all the foam insulation in that area and use the top of the ping-pong table, now roughened with Liquid Nails, as the pond's bed.
I have instructions for painting the bed in two books and a DVD, but I don't know the best way to cut the styrofoam to a certain depth (1.5 to 2 inches).
Would any of you care to light my way? I'd really appreciate it.
--Jaddie
Unless you want a truly ghastly mess, DON'T use a router on styrofoam!
When carving foam, my weapon of choice is a steak knife.
You could cut all the way through the foam (you didn't specify thickness) and then build back up with drywall mud, ground goop or plaster to get the depth you want. If you intend to use one of the pourable plastic 'water' products, you will have to make sure that the pond bed is sealed so it won't flow to unwanted places.
Just my . Others will have advice, possibly better than mine.
Chuck (Modeling Central Japan in September, 1964)
Hi Jaddie,
We have had several experiences with styrofoam in our house; MRR, school projects, drama props, etcs. In all cases we've used a homemade hot knife to sculpt the product.
Take your good-ol Weller soldering gun and remove the tip. Replace the tip with a loop of #14 guage solid copper wire - about 12" formed into a loop. You will need to replicate the bent ends of the original Weller tip and use a couple spare nuts to secure to the gun. Then pull the trigger on the gun and wait a few seconds. The wire will be hot enough to melt through the stryrofoam and carve to your heart's delight.
Cheap and easy. Like I said it has served many projects in the family for the last decade.
Keep your stick on the ice.Dwayne A
Remember, you do not need to cut very deeply to give the illusion of a deep pond. Chop out the shape and maybe 1/2" to 3/4" deep at the most, depends on how much shore incline you want on your shore. It doesn't need to be a very smooth job.
Use plaster or similar material to seal and generally shape the botton of your water. This makes a tight seal so that your "water" will not find a place to leak out.
Once that is dry, paint the deep areas with a dark green, brown or black (really deep). Then use your earth tone from the shore in. Be sure that both paints are still wet and gently blend them together. This gives you the illusion that it gets gradually deeper. When you make your "water" pours, most should not be poured more than 1/8" at a time. Unless you want very clear water, you can add a little olive or brown craft paint (just a few drops usually do) to the first mix to give a merkier look. A little less paint in the next pour, then clear for the surface layers. Be sure to have something that you can cover the water like a tent with while it dries. This keeps dust and other unwanted "stuff" from getting stuck in your water surface.
If you want to indicate choppy water or moving water, use a product like WS Water Effects on the surface. I haven't done that, so I'm only telling you what I have read here on that part of it.
Oh yes, Be sure if you want features like rocks or vegitation sticking out of the water, that it is in place before you make your pours.
Good luck,
Richard
I started with this as the site of a modern high-tech swamp:
I used a utility knife, cutting the flat surface about a half-inch deep in a grid about a half-inch per square, and then I dug it out with a knife and a spoon.
That's really about all the depth you need. The difference between a shallow swamp, a pond, a river and a deep harbor is all done with paint. Darker paint makes the water look deep, and light paint makes it look shallow.
Yes, I really used a spoon.
It takes an iron man to play with a toy iron horse.
Dear Richard
My problem with arriving at something like a 3/4-inch depth is in having the entire area be exactly 3/4 inches deep.
In Dave Frary's book How to Build Realistic Model Railroad Scenery, he says the top of the water bed should be 1.5 to 2 inches below the base level. I believe I'll cut out all the styrofoam in the shape of the pond and then fill it back in with about a quarter-inch of plaster.
Jaddie,
How low the surface of your pond is below the main surface of your layout is depends on your plan. My ponds surface is just below the main surface of the layout. If you plan to have a river or stream needing a bridge, yes you need more depth. For mine I only cut down 1/2".
You can cut out a chunk of the foam. Then use some latex caulk to stick a piece of plywood or foam a few inches larger than the hole to the underside of the layout. Then I would form the bottom of the pond with Sculptamold (plaster that thick might not perform well). When dry, do as mentioned above.
After I cut through the styrofoam, there'll be a ping-pong table top (fiber board, I think). Can't I put Sculptamold on top of that?
I love Sculptamold.
Don't know why you can't put in the Sculptamold right on the table top as long as your foam is adheared to it also.
Hi
Take your bread knife or steak knife measure just over the required depth along the blade wrap the blade with masking tape or similar, this will give you a simple way to cut to depth.
Do this with great care to avoid any nasty cuts blood is not a valid scenic matierial and it could put pay to modeling for a few weeks.
Mark out your pond run a cut around just inside the edge of the pond allowing for the slopping the bank later.
Next cut a grid pattern in the pond now cut out the square bits this will give you the pondish shape that is slightly over depth with a very rough bottom now shape the banks.
Once done smooth over the banks with plaster or similar and mix some thin plaster to a batter cosistency pour this into the base of the pond to the desired depth leave to dry.
The base may crack as it dries if it does when dry fill the cracks with stiff plaster and smooth out.
Once dry leave it for a day or two just to be sure.
paint to taste then once dry add what ever you are using for water along with any thing meant to be in the water.
regards John
Jaddie --
I would proceed similarly to several other recommendations above. First of all, try taking your router to that styrofoam, just once. It will be a good life lesson in what not to do!
Where I can get at the edge of my styrofoam, my cutting tool of choice is a compackt hacksaw (the handle clamps one end of the blade, leaving about 6" of blade exposed to cut with). Otherwise, I use a Sureform rasp, and have a small over the shoulder vacuum to keep the mess under control.
While a hot knife / wire does cut well, I am always leary of the fumes it generates. Many of them are toxic, they all smell horrible, and I'm not convinced it really workds any better.
What I would do is use a knife / hacksaw blade to carve the outline of the pond (try to cut in at the angle of the bank, although you can clean it up with the rasp later), hack out the big chuncks of foam with the blade, then use a rasp to get a rough level. Cover the base with Sculptamold to create a level surface -- although it doesn't need to be perfectly level. You can also go right down to the ping-pong table. Sculptamold will stick to that just fine.
Connecticut Valley Railroad A Branch of the New York, New Haven, and Hartford
"If you think you can do a thing or think you can't do a thing, you're right." -- Henry Ford
If the full 2" depth seems too deep for the base, grade off the banks and surrounding "level" area. I would remove the foam and build up the base w/ 3/4" foam, ply or MDF. A small pond, lake or other water feature won't need that full depth unless you can cut down the surrounding scenery.
Modeling B&O- Chessie Bob K. www.ssmrc.org
I have used rasps in the past to gouge out rock formations, river beds and the like, and this has left me with good results . Have fun.
matthewd5Can we talk more about the method of carving out the water features using the soldering gun? My layout is 4x8 and has both a 2' long river plus a harbor and my river would come out much nicer if I can shape it with the soldering gun Matthew
Sure.. but if you've read my previous posts, you'll know that I recommend against it. Using heat and styrofoam together makes fumes which smell horrible at best and are txic at worst. Plus, a wire cutter makes unnaturally sharp edges that need to be softened, and a soldering iron is hot enough to entail an unnecessary (for this project) of severe burns.
I would be more curious to understand why you think you will get better results if you use the soldering gun, because I don't think that's necessarily true.
well my layout has a 2' long river somewhere between 2"-3" deep and it leads to a bay/harbor
my thinking was with a carefully shaped cutting wire i could not only cut out the depth of the river but perhaps help with the slope along the riverside vs. having to hand cut the banks of the river...
that and being able to carve out your river without cutting through to the plywood underlayer would make pouring the magic water for the river would be cleaner and more straightforward
matthew
Matthew,
Notwithstanding the warnings of working with hot Styrofoam I offer the following:
Back in the 80’s some friends at church were making props for a drama production. They needed to create mushrooms as large as and larger than the kids (2-4’). They had glued together sheets of 4” Styrofoam and were carving the foam with knives.
Even in the 80’s I was a student of Tim the Tool Man Taylor and knew in my heart that any task done with rudimentary hand tools would be enhanced by adding watts and HP. Thus was born the Weller Styrofoam forming tool pictured below.
Note the little bends on the ends of the wire to fit into the tip holders on the gun.
Since that time the forming tool has been used on a couple more drama productions and school projects involving mountains and manikins. I personally don’t use Styrofoam on my MRR (I prefer cardboard web and plaster cloth) but if I did this would be my tool of choice.
The cautions posted above by other modellers are wise. The strings of hot melted Styrofoam WILL burn you if they contact your skin. I recommend wearing a smock you don’t like, leather gloves and safety glasses. As well, the hot Styrofoam is noxious so good ventilation is a must. We’ve always worked in a garage with the overhead door open.
Good luck. Keep your stick on the ice. Dwayne A.
PS. Thanks to Randy for teaching how to easily include pictures in posts to this forum.
Using a "Hot wire" or modified soldering gun/ with wire to cut out for the river or other larger areas for water will be rather difficult to cut a perfectly flat and level river bottom. Of coarse it can be done, but is messy and the fumes are real bad. Been there, done that. Cutting out the foam to your plywood base, then adding thinner foam to build up to the bottom elevation needed. will be a far better way to end up w/ a relatively flat base to pour water. The embankments can easily be cut/ shaped w/ a serrated knife, fine Sawzall blade (hand held) or many other cutting methods.
Ok I'm starting to think I'd actually have more control making one single cut and then pushing the two halves of the foam apart to form the river and then using a really strong adhesive to mount foam to 3/4" plywood and sculpting the river bank
im just concerned about making each half of the river's edge waterproof and then also making it look realistic as far as the sloping into the water from land
im thinking I need to get the woodland scenics DVD on making water features, I plan on using Magic Water as my water filler
Yes, I would just carve your river out of one piece and not split it. If you happen to cross a place where two pieces of foam come together, so be it,, a plaster lining will take care of it.
When you put in the plaster to form the leak proof base, you can slope the sides of the river/pond as you would like them to look. It also makes so that the carving of the base need not be perfect. The plaster will smooth over the bumps and divots left from carving the foam.
Just remember that the river does not need to be deep. Shading the bottom with paint will give you the illusion of depth.
If, by advanced, you mean a technological solution, you could always invest in a laser guided milling machine. But that's overkill.
The Mark 1, Mod 0 Shurform rasp has been my go-to choice for foam carving for a decade. It's quick and easy to make realistic land forms. It really doesn't take that long to make a good-sized trench. It's kind of like the hammer in that sense -- it's been around for thosands of years, but technology still can't improve on it much.