Styrofoam is lightweight, easy to color and is a perfect material for many arts and crafts projects. It is not at all difficult to cut it into whatever shape you need, but you have to choose the right tool according to your needs. You can do this manually using a pastry cutter, knives or box cutters. You can use an electric knife or hot wire bow to get a crisp, clean cut. Whether you want to create a handcrafted element of your cosplay costume, custom Christmas tree decorations or stage designs, you can cut the styrofoam as you wish in no time!
Steps
Method 1 of 3: by hand
Step 1. Use a straight cutting blade
Tools with blades, such as knives, box cutters, scalpels, or hacksaws, are perfect for shaping Styrofoam, especially if you don't need to make curved incisions. To get a clean cut, run the cutting edge over an old candle before proceeding.
When applying the wax to the blade, make sure it is white to avoid transferring the color to the plastic
Step 2. Use dental floss to cut the styrofoam panels
This commonly used item is a perfect tool for straight cuts. Lay the panel on a surface, taking care to leave the wire under it; align the latter with the area to be engraved and place a hand on the panel. To cut, pull the far end of the thread towards you.
Step 3. Thanks to the pastry rings you can obtain particular shapes
If you have a relatively thin panel of plastic material (no thicker than 5cm), you can use a cookie cutter; just press the cutting edge onto the panel until it pops up on the other side. The styrofoam pieces will have the shape of the mold you used.
Method 2 of 3: with Electric Tools
Step 1. Use an electric knife to shape the thicker pieces
If you have to "saw" several pieces at once or cross a very thick panel (several centimeters), the best tool to use is an electric knife, which allows you to make straight cuts, but also cuts with gentle curves.
Step 2. Use a foam jigsaw for the larger pieces
This tool is the best solution when you have to cut out large polystyrene "bricks", such as those used to pack televisions or other large appliances; however, it is also the most expensive tool, with a price ranging between 120 and 350 euros.
- Typically, just turn on the hacksaw and rest it on the block you want to shape, being careful to keep your hands at a safe distance from the blade. Consult the manufacturer's manual to find out the specific directions for use of the model in your possession.
- When opting for power cutting tools, wear a mask and safety goggles; electric blades can generate a "polystyrene dust" similar to sawdust, but which irritates the lungs if inhaled.
Step 3. Use a hot wire headband to get well defined lines
This tool melts the material thanks to a hot thread, leaving the edges smooth; it is particularly effective for curved lines or for modeling polystyrene.
- Slowly apply steady pressure as you run the yarn along the cutting line you want; if you move it too fast, you can break the thread.
- Use extreme caution when using such a headband, as the wire is hot and can cause severe burns.
- Hot wire bows are excellent tools, because they generate very few polystyrene crumbs and allow you to make clean cuts.
Method 3 of 3: Make the Various Cuts
Step 1. Follow the project instructions
Sometimes you have to make curved cuts first, in other cases straight ones; you can proceed as you prefer, as long as you respect the instructions on the work plan.
If you are making a project designed by yourself, for which you have established the instructions yourself, you can start independently with curved or straight cuts; remember that it is your craft work and therefore there are no rules
Step 2. Make smooth back and forth motion when using a blade
Maintain constant and firm pressure throughout the process to minimize the risk of breaking or crushing the material; by doing so you also reduce the formation of crumbs and polystyrene dust.
Step 3. Cut out notches in the center of the styrofoam
If you have to make a depression in the material, start from the center; draw a line around the portion you want to remove and choose the appropriate tool, which also allows you to reach the depth and angle of the curvature you want.
- The knife lends itself to the creation of a recess with vertical walls; choose the right length blade and cut along the line you drew.
- In some situations you can do a better job with a round sanding tool.
Step 4. Practice canals using a bladed tool
In this case you should use a serrated knife or an electric one, as they ensure the best results. Trace the outline of the canal delimiting also its depth and consequently insert the blade into the plastic material; when the extra piece is loose, remove it.
You can use this technique to make channels that go through the piece of styrofoam or run along its surface
Step 5. Divide the Styrofoam balls by cutting them in the middle
You can get two hemispheres by drawing a line along the equator with a ballpoint pen; in some cases there is already a line made by the manufacturer. Use a sharp blade, hot wire bow, or electric knife to make the incision.
