With all of the new uses people are finding for different materials to use in model building the one that is coming into use more than others is "Blue Foam Board" used in construction as insulation, in sizes up to one inch thick.
A four-foot by eight-foot sheet of foam board goes a long way on most projects and the cost isn't prohibitive to those on a budget.
I've seen different tools used for cutting foam, but didn't want to put out the money that they cost. At the ECLSTS in April of 2004 I bought a hot foam cutter the "Tippi Hot Foam Cutter" was in the price range I was looking for. Also I wouldn't be out a lot of money if I didn't like it.
After trying it out at home I find it will do what I had in mind.
I have used foam in many ways for modeling. After seeing the building projects Chris Walas and other modelers have made using foam as base material. I have wanted to try it also but didn't have the proper tools.
A few tools that are most people have on hand for scratch building will do. With the addition of a hot wire cutting tool, add your imagination and you can come up with some very impressive items for your railroad.
The only advice I can give is, get a piece of foam board and practice cutting and shaping it to become familiar with this new material for modeling. Try experimenting with different tools to put different finishes and textures into the foam.
I purchased a four-foot by eight-foot by one-half inch thick sheet of the blue foam from Lowe's to work with. I've been told that the "Pink Foam Board" works just as well as the blue.
I want to thank Chris Walas for letting me use some of his comments from net and the use of a couple of his images.
The tool I have is a "Tippi Hot Foam Cutter".
It came with One shaped cutting wire in the tool, with three more cutting wires bent into different shapes, also 2 extra straight wires that can be bent to any shape you want. I bought the package offered at the show so I could receive the "C" shaped Cutting attachment for making deep cuts plus the cleaning brush at no extra cost.
Following are comments from different post made by Chris Walas on the hot wire cutter and using Blue Foam Board.
On the Tippi hot foam cutter.
In my never-ending search for good foam working tools, I bought the Tippi Hot Foam Cutter by Premium Concepts of Presto, PA. (Presto. The show price was $39.95. This appears to be a tool that was previously marketed by Avalon Concepts.
Included is the basic hand tool, transformer, a selection of four pre-shaped wire blades and "for a limited time" two spare unshaped wire blades. A hot wire coping saw attachment is available.
This is a simple hot wire tool and like all the others has its good points and bad.
On the plus side, the Tippi tool is light, the wire blades are easily changed (two hand screws), it heats up quickly, and I like the color.
On the down side, the Tippi's wire blades are rather thick and tend to cut a wide swath through the foam.
Fine detailing is impossible, as there's no pointed tool.
One of the big negatives in my book is that, like several other foam tools, there's no real heat regulator. A pressure button controls the Tippi; as long as you're pressing the button, it's heating.
When the foam starts smoking, you're supposed to let go of the button and let it cool.
The Tippi does work, and work well enough in certain applications.
But for rough working of foam, the Tippi tool will probably do the job.
Compared to other foam tools on the market, I'd say it's somewhere in the middle.
I was able to sculpt some rough detail with the Tippi tool on a cartoon house.
All in all, for the price, I'd say the Tippi Hot Foam Cutter is okay. As far as a foam tool that does everything, there isn't any such animal.
The blue foam holds up extremely well outdoors. I rarely get a frost on the ground out my way, but the cold doesn't seem to affect the foam.
Sunlight "UV" seems to be the only real concern, as non-coated foam will break down in direct sun. But even just a coat of good paint will stop that.
I've whittled it down to a couple that I'm happy with. The #1 choice is the one I started out with, exterior latex house paint, two or three coats. It seems to go on the easiest and doesn't cover as much of the detail.
The second is an "Acrylic Elastomer" roof coating, "Henry's Solarflex 287", two coats. It remains flexible after drying and has a tough skin, but fills in a little more of the detail. Both take acrylic paint well.
I don't use any structural support on my foam stuff.
The Ruined Lemurian Temple is the largest structure I've done.
It is (19"Lx16"W x 29"H) and it is a very sturdy structure.
I've found Titebond II to be the best all around glue, but it takes a while to dry, so I do as many before me have done and dry wall screw the foam together. I've also used Weldbond and Liquid Nails. They both work.
Another suggestion about anchoring the foam; I use Galvanized
dry wall screws, screwed and glued into the bottom of the foam and bury the head of the screw.
This grabs both the foam and the ground giving the screw a little more hold to keep everything in place.
Since I do not have a steady hand anymore I couldn't keep the wire at an even depth while using the Tippi and needed a Depth Gauge to help out.
My solution was to make my own gauge from wood scraps and super glue. The terminals do not get hot enough to melt the plastic. So I used a small plastic clamp to hold the gauge to the tool.
As you can see It wasn't a complicated thing to make. The smaller piece was made to go between the two terminals keeping the gauge from slipping out of the clamp when moved across the foam surface. A tight fit between the terminals will hold the Gauge best.
With a little practice using the gauge becomes easier. Learning to control the heat is the hardest part. But with practice that becomes easy also. I use a thin strip of wood as a straight edge to make a straight cut. I also use the Gauge when working free-hand to control the depth of the cut.
When I started to make my first try at using the hot wire cutter, it will be referred
to from now as the "Tippi", I laid-out the design on the foam board using a rule and straight edge for guide lines.
I found that I could use a thin strip of 3/4" wide stick to lay out large stone work. Just lay out a row and move the stick down under the last line and make another line. To get the length of the blocks, I lay the stick along one edge and mark every other row, move the stick so the stick lines up with the first marks you made, then mark every other row that wasn't marked the first time, move the stick to the line just made and mark the same rows that were marked the first time. If You have marked things right you now have one set of blocks marked to length. By repeating marking and moving the stick you should have the hight and width of your blocks.
For some styles of stone work this is the only way to go. There are some shortcuts that can be taken for cement or cinder block which will be shown also.
I made my measurements on the foam board.
Using the Tippi with a straight edge and depth gauge I cut the design in foam.
After adding texture to the foam and adding paint it will pass for cement block.
To keep from doing a lot of measuring, I had to come up with a easier way of laying out my work. I bought some Precision Panels a while back and it came to mind that I could use the panels to mark the foam for cutting by laying the panel over the foam, pressing down on the front side of the panel leaving the imprint of the panel on the foam for a pattern to cut by.
The front side of the panel.
Reverse side of the panel.
This is the roller I use to press the design into the foam. I don't know what it is, I bought it for a dime at a yard sale.
Using this method gives a clear pattern to work by, saving time in not having to measure everything.
This shows the three different designs that I prefer to use.
Some things you can do with a Hot Wire Foam Cutter.
There are unlimited designs that you can make with foam board. You are limited only by your imagination. So give it a whirl and see what you can come up with.
The following are some of my experiments into the world of Foam Board
construction types.
I could go into greater detail on making the different styles of stone work. Most of working with foam is a hands on learning process. You see something you like then try to reproduce it in foam. I will go into a general explanation on how to do the different types of stone work.
One type of stone work different from the others takes more explaining in how it is made and I will go into more detail on making it.
Using foam "without" removing the plastic film.
Remember when making this type of stone work to leave the plastic film on the foam board, it is the film that gives the finish to this type stone. This way of making stone lends itself best when making larger stones.
I used a Precision Panel pressed into the foam for a pattern.
After laying out the design. Use the Tippi and burn in all of the lines using a depth gauge.
With all lines burned in go back over all of the blocks with the Tippi wire at an angle putting a bevel on each block. Using the tip of the Tippi wire randomly touch the blocks putting holes through the plastic film.
Now with a propane torch carefully flash the foam.
You should practice using the torch to melt the foam; it takes a quick hand to keep from melting everything. Keeping the flame down low when working with the torch is important so you don't have a complete melt down.
After applying the torch to the foam you can use it in this state or you can remove the remnants of the plastic film remaining on the foam.
Using a pair of needle nose pliers or pair of tweezer remove the film, the black part, pull the film off of the foam base.
The foam now has a completely different appearance. I used the wire cutter to redefine the joints after removing the plastic film.
For all of the following, the plastic film is "removed" from the foam board.
Having the right finish on your project is as important as the type of material you are trying to simulate.
The first time I tried to make a wall I laid out my design used the Tippi to cut it into the foam, and still it looked unfinished.
The surface was flat and I wanted it to have a design of some kind to set it off. I thought about using the Tippi to cut something into the foam. Practiced on a piece of scrap foam and nothing looked right.
Since a wall of this type would be made from Cinder Block or Cement Block it should look like it too. I looked around for something that would give me the desired effect. I settled on an old welder's brush with the steel bristles all bent and broken. I hit a scrap piece of foam with the brush and it gave me the effect I wanted.
I used a new brush one time and all of the holes were in neat rows, so I went back to my old brush.
After making cut stone it needed some thing else, I used the brush to add a few holes to the stone, looked good.
Larger blocks can be used for foundations or bridge supports. I was able to add a texture that looked like concrete by a quick pass with a low flame that melt just the surface of the foam.
Something needed on all layouts are side walks. They are easy to make and can be fastened to the ground by gluing a dry wall screw to the bottom of your sections of walkway. I cut the walkway out with the Tippi and used a ball point pen and a straight edge to make the lines in mine, followed by the wire brush for texture.
I think the next time I make a walkway I will use the torch for the final finish. This will give it a harder surface and be less prone to damage.
This effect was obtained by using a small brush to remove some of the foam as a final step. This has to be done carefully with a very light touch or all of the foam may be removed.
Caution: Never work on anything with the power on. If you make one of these devices be sure that all grounds wires are used and connected. And that the source is grounded also. You can't be too careful with electricity.
Remember you are working with a higher voltage. Check everything twice before turning on power .
As the Tippi Foam Cutter has just an off and on switch and depends on the one using it to control the heat by turning the switch on and off. It's workable but a pain, it is ether to hot or cold.
While at Lowe's, again, I picked up a light dimmer switch to try and control the heat of the cutter.
I used a 4X4 Square electrical box, a switch extended plaster ring, male and female plugs and 4 foot or so of 3-conductor rubber cord. Two Romex wire connectors and a half-hour of time and made a heat control box for the foam cutter and wood burning tool.
Caution: Using a regular work box and plaster ring as I have, the unit will not be waterproof and is not for use in wet or damp locations. All grounds were connected to help insure safe use.
Everything worked fine. A little playing around found the best settings for the heat I wanted.
While make long cuts with a straight edge I didn't need the Depth Gauge as before because the wire didn't get as hot and cut deep into the foam as when full heat was applied.
Since the wire wasn't as hot the cut was just the width of the wire.
Note: During normal use of the tool without the voltage control, the transformer does get slightly warm to the touch. There was no noticeable temperature rise in the Dimmer Switch or the step down transformer in the half-hour I used it.
All in all I'm satisfied with the temperature control unit.
If I find there is a problem with this set up after continued use I will post it here.
The Tippi tool is all right for heavy lines when working with foam, there are times that I wanted to do fine detail work.
Making the grain in wood and other fine details was made possible by using a lighting dimmer switch to control the temperature of the wood-burning tool. By modifying the removable tips that came with the tool I can worked the details into the foam surface.
The wood-burning tool I am using lay under my workbench for Twenty odd years gathering dust till I decided to give it a try.
"Using the Wood-Burning Tool"
Once you get use to setting the temperature of the tool it is easy to use and work with. After finding the right working temperature I marked the dial on the dimmer switch so It will take less time to get the temperature set the next time I used it.
Each time I use my tool, it needs fine tuned for the work I'm doing.
I do my layout on the foam as mentioned before using a ruler and square, or to save measuring every row for stone work I still use different size "Precision Panels" to press the design into the foam as a guide.
With the Tippi foam cutter I had to use a strip of wood as a guide for cutting straight lines so the wire cutter doesn't short out. With the wood-burning tool I can us a metal straight edge.
The tool I have is rated at 20 Watts. The price tag of $5.00 was still on the package. Glad I remembered I still had it.
I reworked the different tips that came with the tool for working at the lower temperatures I'm using. I turned the one tip into almost a needle shape for fine work. Another tip to use the same way I use the Tippi cutter.
The work in the picture above was done entirely with the wood-burning tool. I was surprised how much can be done using just the wood burning tool.
Adding Texture or Grain in the Foam
The foam surface can be left smooth or texture and grain can be worked into the foam. With experimenting and practice you find every day objects that you can use in working with foam. Wire and hair brushes, coarse sand paper are a few things you can use. Each giving a different finish to the foam surface.
It may seem to some people that the texture I put on my foam work is to harsh or over done. My thinking on this is that most of my and your work is not seen close up and details may be lost if they aren't bold enough to stand out.
The two examples below on th left bold and right a lighter touch.
When laying out my work on foam I use the colored pens used for screen projectors that wipe off with a wet cloth. As you can see by the above picture I used a green and red markers. The red was permanent ink and didn't come off.
I used a small, well worn, wire brush on this surface. You must be careful and use a light touch or you may remove to much material. I'm still working on this type of finish trying to get the "Fuzzy" look toned down. Painting may take care of that though.
I put a light coat of paint on the right side and it seems to remove the fuzzy look. More paint will probably give me a better idea of how the finished building will look.
"Painting"
I use Acrylic and Acrylic Latex paints on my foam work. There are several companies that make paint just for Foam.
Even though it isn't just for foam, I use "Red Devil" Acrylic Latex paints on most of my work made with, foam, metal, plastic and wood.
I like a nice neutral color for a base coat, I use the Almond, Red Devil, Acrylic Latex paint. The Almond color covers well even when painting over with yellow.
Tools I use on Foam
To add texture to my foam building projects I have tried just about everything to see what it will do to the foam surface.
After trying different items I settled on those in the picture. The hair brushes are different sizes and stiffness'. The baby brush is soft and I use it to clean up the finished surface of loose material without changing the design.
The blue item, upper left is used for foot care. I use it as a file. It has a convex and concave side and has been a very handy item.
The welding brush is very stiff and is my favorite. The roller is used to transfer the design of the plastic
Precision Panel into the foam surface to save time laying out the work piece design.
The small wooden handled brush is the one I use to add the strata look to the stone work. The wire bristles in the brush are bent from use and give a random look to the work piece. It takes a little practice to learn how much is enough when using it on the work area.
How I put my Buildings together and Anchor them to the Ground
Gluing Buildings together
There are a lot of ways you can put your buildings together, this is my favorite.
Types of Glue
Chris Walas: "I've found Titebond II to be the best all around glue, but it takes a while to dry, so I do as many before me have done and dry wall screw the foam together. I've also used Weldbond and Liquid Nails. They both work."
One problem with most glues that do not set up fast is finding a way to clamp everything together till the glue sets up. When gluing plastic cardboard buildings together I use a glob of hot glue on the joint to hold it together till the glue sets. This doesn't work to well on foam structures as the glue melts the foam.
The picture above shows the way that works best for me.
The main part of the building is made from 5/8" Foam with 1" square blocks of Foam fastened with Titebond glue and 1-1/2" dry wall screws.
I first applied glue to the sides of the 1" blocks in contact with the wall sections, pressing them into position in the corners to spread the glue evenly on each piece, separated them and let the glue set up for a few minutes, then replaced them pressing them into the corners to get a good seal with the glue. Make sure each section is aligned then screw the dry wall screws through the blocks to hold everything together till the glue has set. The screws can be left in place or removed, I left mine in.
Anchoring Buildings to the Ground
Buildings made with Foam are so light that weight has to be added or Anchor the building to the ground.
Some people glue their buildings to a heavy base to keep it in place. Another way is to Anchor the building to the ground. This has been suggested by Chris Walas and others.
Chris Walas: "Another suggestion about anchoring the foam; I use Galvanized dry wall screws, screwed and glued into the bottom of the foam and bury the head of the screw. This grabs both the foam and the ground giving the screw a little more hold to keep everything in place."
