Yr.10. Unit 2. Line Bending

Shaping Plastic

Line Bending/ Strip Wire Heater

Shaping Plastic

Plastics are one of the easiest materials to shape. Thermoplastics, such as acrylic, can easily be bent, pressed or blown into shape at a temperatures around 160°C•Plastics are one of the easiest materials to shape. Thermoplastics, such as acrylic, can easily be bent, pressed or blown into shape at a temperatures around 160°C

​What is a Strip Heater?

• Plastic can be formed (shaped) in different ways

• One of the most popular methods of shaping plastic materials is to fold (bend) it on a 'strip heater'

• Strip heaters use a heating element extending along the length of the heater unit & gives off intense heat when turned on

​How does it work?

• Line bending is a process whereby a peice of plastic is bent along a narrowly defined "line"

• A electrical element is mounted below a narrow opening or channel between two pieces of heat resistant material or metal bars

• The element begins to heat the surface of the plastic sitting above it

• The plastic begins to soften along the line of the heating element and becomes flexible and pliable

​Shaping Plastic

​•Once heated the plastic can be shaped to the correct angle, either by hand or by using a simple former or jig

​Material and Application

​•Line bending products often consist of display stands, plastic boxes, leaflet dispensers, or furniture such as outdoor furniture or acrylic tables. Line bending is used to create simple shapes, where the clean look of the product is a primary focus.

•Whilst line bending is limited to the production of plastic products, a range of plastics can be used to meet product requirements such as acrylic, Rigid Polystyrene & Perspex 

​Advantages

​Dis-advantages

​No additional tooling required

Creates seamless bends, straight bends with small radiuses can be created

Relatively simple process

Plastic can be reheated and reformed if the process is miscalculated, reducing scrap and manufacturing costs.

​Only simple shapes can be created

Former or jig is required shape the plastic

Restriction to the number of bends in a single sheet

Stress bends can occur which can deform the plastic

Additional processes such as cutting may be required.

​Safety

​•Wear safety glasses

•Keep fingers away from heated element

•Take care when handling HOT plastic

•This machine is a fire hazard! Keep away from flammable materials, and never leave the machine unattended when actively heating plastic.

•Inform a member of staff if the machine is damaged in an way

•Do not touch damaged wires

Open Ended

State what safety precautions you would use we

hen operating this machine

Multiple Choice

At what temperature can thermoplastic be formed

• 1000°C

• 160°C

• 560°C

• 330°C

Multiple Choice

Choose an example of the products produced using the line bending process

• Yougurt pots/ Air ducting

• Leaflet dispensers/ display stands

• Bottles/ Lunch containers

• Wires/ Pipes

Multiple Choice

Choose an advantge related to Line Bending/ Strip heating

• Can also be used to heat and bend metal

• No additional tooling required

• Creates complex shapes

• Is completely safe to use because the heating element is in a narrow channel

Multiple Choice

Choose a disadvantage of a Line Bender/ Strip Wire Heater

• You can not reheat the material if you make a mistake

• Users require special training to operate the machine

• You need to wear Personnal protective equipment to use the machine

• Only simple shapes can be formed

Open Ended

State a safety rule associated line bending