Extruding

Target Subject: Technology/Engineering

Purpose

To explore the process of extrusion used to produce pipes and wires in industry.

Background information

Tooth paste and frostings are examples of extruded materials. Commercially prepared frosting tubes replicate the process of extruding a softened material such as plastic. The material then hardens into a shape determined by the shape of the opening through which it has been extruded. Using tubes of frosting and different frosting tips students can kinesthetically experience how materials such as plastic are formed in a factory.

Preparation

Before carrying out this activity, as part of a unit on manufacturing processes, the student should examine examples of products produced by extrusion such as wires and pipes.

The students may notice that it is difficult to exert a constant squeezing pressure on the tube.

Materials

• Commercially available tubes of frosting
• Tips of various shapes
• Plate
• Tray

Procedure

1. Select a tip to be attached to the frosting tube after the cap of the tube is removed.
2. Using a constant pressure, squeeze a line of frosting onto a plate.
3. Place a different tip on the tube and squeeze another line or shape on to the plate.
4. Try creating shapes such as circles and triangles
5. Let the shapes dry for at least 25 hours before examining tactually.

Note: the frosting in tubes also makes an excellent “mortar” for holding together materials in small scale construction projects.