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Working with styrene
This plastic is inexpensive and versatile.
By Jeff Wilson
Published: Saturday, August 31, 2002
 From left, plain, scribed, board-and-batten, and tiled sheets from Evergreen; telescoping round tubing and channel from Evergreen; girder, square tubing, and quarter-round strip from Plastruct; and square strip and H-column from Evergreen.
I find it handy to have a supply of styrene sheet and strips in my workshop. Evergreen Scale Models (www.evergreenscalemodels.com) and Plastruct (www.plastruct.com) are the two major manufacturers, and their products can be found in most hobby shops as well as through distributors such as Walthers.
Another great source for styrene is a commercial plastic retailer (check the yellow pages under Plastics). These dealers sell sheets of plain and colored styrene up to 4 x 8 feet - handy for building large structures, roads, and other projects. You can also find adhesives, polishing materials, and clear acrylic sheets and shapes.
Plain sheet is available in thicknesses from .005" through .100" and thicker, with .020" and .030" among the most common used in modeling. Sheets are also available with many patterns, such as clapboard and board-and-batten siding, tile, and grooved (to represent individual boards). Styrene is most often white, but clear and colored sheets can also be found.
Strips are available in standard dimensions (with square and rectangular cross sections) as well as in rods, tubing, telescoping tubing, quarter-rounds, I-beams, Ls, and special shapes such as girders. |
 To cut styrene scribe the styrene with a sharp knife, then bend it at the scribe to snap it in a clean line.
The easiest way to cut large pieces of styrene is the scribe-and-snap technique. Score the plastic with a sharp hobby knife. Use a straightedge to ensure a precise cut. Bend the sheet at the mark and it will snap, leaving a clean line. This method works best for straight lines and gentle curves. You can use scissors to cut thin styrene, and tin snips work well for cutting thicker stock.
Strips can be cut with a hobby knife, single-edge razor blade, razor saw, or with a tool such as NorthWest Short Line's Chopper.
Styrene is easy to work with. It can be shaped and contoured with almost any hand tool, including hobby knives, full-size and needle files, scribers, dental picks, and sandpaper or sanding blocks.
Drilling holes is easy using a pin vise. I suggest buying a set of no. 61-80 drill bits, but you can use a pin vise to drill larger holes in plastic as well.
You can use a motor tool to drill styrene, but be sure to use low speeds. Working at high speeds causes heat to build up quickly, and this heat can distort the plastic. You can also use a motor tool to grind styrene using steel router bits of different shapes. Once again, use slow speeds and pause frequently so the plastic doesn't melt. |
 If you apply liquid cement with a brush, capillary action will draw it into the joint.
Plastic solvent cements all work by the same principle: The solvent in the glue melts the top surface of each piece of styrene, bonding them. When the solvent has evaporated, the resulting joint is as strong as the styrene itself (as anyone attempting to disassemble a plastic kit discovers).
I use two types of plastic glue. The first is Testor's Liquid Cement for Plastic Models (no. 3502). This is a thick liquid solvent applied with a needlepoint applicator on the bottle. To use it, apply the glue to one surface, then press it in place.
The second type is liquid solvent applied with a brush. Hold the parts together, then touch a brushful of solvent to the joint. Capillary action will draw the adhesive into the joint. Some liquid cements, such as Tenax, evaporate very quickly; others, such as Testor's no. 3502, evaporate more slowly.
Cyanoacrylate adhesive (CA) works well for joining styrene to other materials such as wood, brass, and resin.
Painting
Styrene takes paint well, and any of the common modeling paints - acrylics, enamels, or lacquers - can provide a good finish. However, be aware that the solvent in lacquers, such as Scalecoat and Accu-paint, can attack plastic. I use acrylics whenever possible because of the ease of water cleanup and the absence of toxic vapors.
The key in getting a good finish on styrene is to make sure that the surface is free of dust, grime, and oil (such as from your fingers from handling). Any of these can keep paint from adhering to the plastic.
Scrubbing the surface with a toothbrush using liquid dish detergent in warm water is generally sufficient to clean the surface.
An airbrush or spray can will generally provide the best, most even paint finish, but brush-painting can also yield good results.
Jump in
Break out some styrene and start with an easy project like a small shed or length of sidewalk. Or, better yet, just try playing with it to see what you can make using this flexible and easy-to-work material.
Jeff Wilson is a former associate editor for Model Railroader magazine. |
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