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The fretsaw is a general workshop machine. It is used to cut and shape light materials such as perspex, MDF and plywood. Fretsaws are made by different companies and they range in price depending on the quality of machine. The most expensive and probably the best are manufactured by the German company ¡®Hegner¡¯. These can be used to cut very detailed shapes and they are supplied with different types of blade according to the material that is to be cut. Cheaper fretsaws are still very useful and they can cut a range of materials. The materials cut more easily if they are quite thin, for instance, any material thicker than 10mm would be difficult to shape. The general rule is that the thicker the material, the slower the machine operator pushes the work against the blade.

Although fretsaws are common machines they are still dangerous if the operator is careless and if he/she does not keep in mind safe working practices. It is important to use the guard because this is the first line of defence if a blade breaks. Goggles should also be worn for eye protection. The operator should know where the ¡®on¡¯ the ¡®off¡¯ buttons are and be able to use them. The material should be fed into the blade slowly and it needs to be gently held down on the table of the machine as this will prevent it from vibrating. The fretsaw should not be turned off whilst the blade is cutting the material especially if the material is then moved - this could twist the blade and it could be broken or damaged the next time the fretsaw is turned on.

The fretsaw blade can be seen to the right. The blade is always set up in the fretsaw with the teeth pointing downwards. If the blade is set up the wrong way round, with the teeth pointing upwards - when the fretsaw is turned on the material will lift from the table and the blade may shatter.

1. Draw a fretsaw and label the most important parts.
2. List safety factors regarding the use of the fretsaw.
3. Demonstrate the use of the fretsaw to a group of pupils, emphasising safety.