Working with plastic or styrene sheet – top tips

Plastic sheets are sold by a variety of manufacturers, in different colours, and with different thicknesses, though they all respond to the same treatment. There are three stages to working with plastic sheet - the cutting of parts (ensuring that cuts are perpendicular to the surface), the cleaning of parts to ensure a good bond with a solvent adhesive and the gluing of these in their correct location.

Here are some top tips.

For your safety, always use a steel rule when cutting parts with a craft knife. Plastic rules can be cut easily by steel blades. When cutting a straight line, measure across at both ends, pressing the blade into the plastic sheet each time to create an indent. Join the two indents together by placing the rule in one indent at a time and aligning the rule at either end. DCC concepts retail this plastic sheet with millimetre cut guides that facilitates the measuring of components to scale.

Before making your cut, ensure your fingers aren’t in the path of the blade. You must press down firmly on the rule, not the knife. Start at the far end and gently draw the blade along the edge of the rule, applying only a small amount of pressure to the knife, still holding the rule firmly in place. Only cut through half the thickness of the plastic sheet, for which a few passes – more for thicker sheet – will be required. The sheet can be snapped along the cut line, keeping the other edge of the plastic sheet free of cut mounds along its edge.

Plastic sheet components benefit from a clean before assembly to remove cut witness marks or raised edges left by the passing of the knife. Needle files can leave scoring if not held correctly or when excess pressure is used on this soft material. Sanding sticks are widely available from suppliers such as Albion Alloys and make swift work of rough edges. Removing the ‘sheen’ from the surface of the plastic sheet always guarantees better adhesion with glues.

Plastic sheet can be glued using superglue, two-part epoxy resins or a solvent. The last-mentioned is best because it leaves little trace of glue behind and fuses the two plastics together to create a stronger bond. Superglue and two-part epoxy resins leave traces of glue behind and don’t penetrate the plastic surface to the same extent. Work in a well-ventilated space to avoid breathing the evaporated solvent fumes. Devices such as this Proses magnetic clamp provide a useful extra pair of hands for holding parts together at a 90-degree angle.

Need more advice? Take a look at the BRM Techniques page for all our latest guides and advice articles.