1. Choose 2 machines that you used in the fabrication of your desk tidy. With these machines in mind, outline WPH&S considerations that must be adhered to when using these machines. Include photographs of your chosen machines (OnGuard may be an excellent resource for this question).
Safety procedures
· Wear safety glasses or a face shield.
· Wear hearing protection that is suitable for the level and frequency of the noise you are exposed to in the woodworking area.
· Wear protective footwear when required.
· Ensure the blade is tracking correctly and runs freely in and against the upper and lower guide rollers.
· Use band saw blades that are sharp, properly set and otherwise suitable for the job (e.g., the right tooth pitch; tooth form; blade width).
· Hold stock firmly and flat on the table to prevent the stock from turning and drawing your fingers against the blade. Keep hands braced against the table.
· Keep your hands on either side of the blade - not in line with the cutting line and the blade.
· Do not stop a band saw by thrusting stock against the cutting edge or the side of a blade immediately after the power has been shut off.
· Do not remove sawdust or cuttings from the table by hand or with compressed air. Use a stick or brush.
· Do not leave a saw running unattended. Turn off the power and make sure the machine has stopped running before leaving the area.
REFER TO PICTURE FOR DIAGRAM
Electric belt sander-
· Always wear safety goggles and a dust mask
When sanding, especially sanding over-head.
· The machine is not suitable for wet sanding.
· Do not use sanding paper larger than needed.
Extra paper extending beyond the sanding pad can also cause serious lacerations.
· The dust bag shall be equipped with the tool.
It shall be emptied frequently. To connect dust bag, insert the adapter of dust bag to the dust-collection opening on the rear end of the sander.
WARNING
· Do not throw sanding dust on an open fire
because materials in fine particle form may be explosive.
WARNING
· A suitable breathing respirator must be worn
while sanding lead paint, some woods and metal to avoid breathing the harmful/toxic dust or air.
REFER TO PICTURE FOR A DIAGRAM
2. The material you are using for your desk tidy is called Polymethylmethacrylate (ACRYLIC). It has specific properties and uses. Choose 2 other common polymers and in table form give their industrial name, common name, properties and uses.
Poly (styrene)
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Nylon 66
| |
Industrial name
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Polystyrene
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polyamide
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Common name
|
Styrofoam
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Nylon 6/6
|
Properties
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» Density – 1.05g/cc
» Dielectric constant – 2.4 to 2.7
» Thermal conductivity – 0.08 W/(m.K)
» Young’s modulus – 3000-3600 Mpa
» Tensile strength – 46 to 60 Mpa
» Melting point - 240°C
» Water absorption – 0.03 to 0.1
|
» Glass transition temp – 50°C
» Melting temp - 255°C
» Amorphous density at 25°C: 1.07g/cm3
» Crystalline density at 25°C: 1.24g/cm3
» Molecular weight of repeat unit – 226.32 g/mol
|
uses
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· Imac computer cases
· Drinking cups
· Model cars
· Styrofoam
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· Fabric for clothing
· Shock absorbers at high temperatures
· Intricate peices
|
3. Extrusion, injection molding, compression molding, vacuum forming and laminating are examples of common manufacturing processes used with polymers (Plastics). Choose one process and with the use of diagrams and bullet points outline the process.
COMPRESSION MOULDING
1. Material placed in open, heated mould cavity
2. Mould is closed with a top force or plug member, pressure is applied to force the material into contact with all mould areas.
3.
Heat and pressure maintained until molding material has cured
Heat and pressure maintained until molding material has cured
REFER TO PICTURE FOR DIAGRAM
4. Extension Work - Using processes acquired from your math’s lessons, calculate the amount of acrylic sheet that your FINAL desk tidy represents. Show all calculations; answer needs to be in square metres.
Working out:
10cm x 11.5cm x 2 = 230cm²
20cm x 16cm x 2 = 640cm²
24cm x 20cm = 480cm²
30cm x 24cm = 720cm²
20cm x 19cm = 380cm²
20cm x 7cm = 140cm²
26cm x 19cm = 494cm²
Total= 2444cm²
= 0.2444m²
My total amount of acrylic sheet that is used to make my desk tidy was 0.2444m²
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