Commercial processes

Offset lithography:

How it works:

1. Digital files are broken down by colour separation
2. The image is etched onto an aluminium plate for each colour, through a laser
3. Each image plate is then loaded onto a plate cylinder
4. The plate cylinder will dampen the non-image area of each file with water
5. A vegetable oil-based paint solution will then be added successively to the plate to imprint the colour
6. The plate cylinder will transfer the colour to another cylinder which is equipped with a rubber blanket that will print it directly onto the paper

Advantages	Disadvantages
High image quality Suited to higher volume print runs of 1000 runs or more Quick/easy production of printing plates Printing plates last a long time	Expensive set-up costs High running costs for small quantities

Uses: Books, business forms, magazines, posters

Die Cutting:

How it works:

1. A sharp steel blade (die) is pressed into a sheet material
2. The die cuts out shapes in one clean movement
3. Often used with a press machine for speed and consistency
4. Can include creasing rules for folding lines

Advantages	Disadvantages
Fast and accurate for high-volume production Can cut complex and repeatable shapes Clean edges with minimal finishing required Can combine cutting and creasing in one process	Dies must be custom-made – expensive upfront cost Not cost-effective for low-volume production Only works with sheet materials of limited thickness Some material wastage from cut-off sections

Uses: Packaging nets, greetings cards, business cards, labels

Routing:

How it works:

1. Material is clamped into place
2. Cutter is selected and RPM is chosen
3. The material always remains stationary while the machines cutting tool rotates
4. As the cutting moves, it presses against the workpiece and shapes the material

Advantages	Disadvantages
Quick process Low skilled Can be done via CNC	Uses electrcity/needs to be plugged in Handheld router can be dangerous if used improperly

Uses: Cabinets, doors

Turning:

How it works:

1. Begin by placing a circular, square or rectangular shaped piece of metal/wood into the lathes drive area
2. The metal/wood piece is typically secured using a pressure pad
3. Once in place, the lathe is activated to rotate and press the mould against the metal/wood piece
4. The rotational force of the lathe then deforms the metal/wood piece to achieve the same shape as the mould
5. When metal/wood spinning is performed by hand, a worker manually presses the mould against metal/wood piece

Advantages	Disadvantages
Complex designs/shapes can be made Energy efficient Good surface finish Can be computer controlled	Dangerous pieces can be ejected from machine potentially causing harm Some materials are very hard to turn

Uses: Table legs, table lamp, engine parts, handles

Note: Turning machines are different depending on the material being used.

Vertical milling:

How it works:

1. Material is clamped into place
2. Cutter is selected and RPM is chosen
3. The material always remains stationary while the machines cutting tool rotates
4. As the cutting moves, it presses against the workpiece and shapes the material

Advantages	Disadvantages
Visibility - can see machine work Can be CNC controlled and so automated Ease of use Very precise	Uses electricity/needs to be plugged in Expensive to buy machines

Uses: Cutting gears, produce slots, drilling

Horizontal milling:

How it works:

1. Material is clamped into place
2. Cutter is selected and RPM is chosen
3. The material always remains stationary while the machines cutting tool rotates
4. As the cutting moves, it presses against the workpiece and shapes the material

Advantages	Disadvantages
Runs faster than vertical milling Very precise Can run at a higher capacity than vertical milling Durable machine - can do many runs No parting lines from mould	Not good at doing radial cuts Machinery takes up lots of space compared to handheld version Uses electrcity/needs to be plugged in More expensive machinery than vertical milling

Uses: Cuttings gears, produce slots, drilling

Sand casting:

How it works:

1. Make a mould in the sand using to half moulds (cope and drag) making sure the corners are rounded/tapered
2. Fix the cope and drag together with nuts and bolts
3. Pour molten metal into case
4. Let it cool and remove mould
5. Apply finishes

Advantages	Disadvantages
Inexpensive Complex shapes can be produced Large components can be produced	Sand moulds can only be used once Surface finish not always good Labour intensive Slow production rate

Uses: Engine blocks, garden furniture, caterpillar tracks

Die casting:

How it works:

1. Create and lubricate the mould
2. Once mould has been created, molten metal is shot under high pressure into the die
3. When the die is full, the pressure is maintained until the metal has solidified
4. The mould is then removed and finishes are applied

Advantages	Disadvantages
High rate of production Good surface finish Economical Precise parts can be made	High set-up costs Long lead time Limited sizes Must be large scale demand for it to be economical

Uses: Taps, model cars

Injection moulding:

How it works:

1. Plastic granules fed through hopper
2. Heated/melted along the Archimedes screw
3. Plastic injected into the mould
4. Two-part mould "negative" of the product
5. Product rapidly cooled and ejected from mould

Advantages	Disadvantages
Ideal for mass production Low unit cost Precise moulding High quality finish	High initial set up costs Moulds are expensive to create Cannot create large mouldings

Uses: Casings for electric products, containers for storage/packaging

Extrusion:

How it works:

1. Plastic granules fed through hopper
2. Heated/melted along the Archimedes screw
3. Plastic forced into the die
4. The plastic is extruded 'pulled' throug the die and cooled
5. Rollers pull plastic continuously
6. The extruded product is cut to the desired lengths

Advantages	Disadvantages
Low cost relative to other moulding processes Uses thermoplastics which can be remoulded Waste material can be reused Plastic can be manipulated after extrusion before fully cooled (e.g. bends/curves)	Hard to predict die swell (expansion) Can only manufacture certain products

Uses: Collapsible tubes, guttering, straws, gear blanks

Weaving:

How it works:

1. Yarns are interlaced at right angles (warp and weft)
2. Done on a loom – can be manual or automated
3. Produces a structured, strong fabric

Advantages	Disadvantages
Strong and durable Can be produced at scale Holds shape well	Less stretch than other methods like knitting Can fray when cut Machinery is expensive

Uses: Clothing, upholstery, curtains, denim

Dyeing:

How it works:

1. Fabric or yarn is soaked in dye solution
2. Dye penetrates fibres – can be done at different stages (fibre, yarn, fabric)
3. Excess dye is rinsed out and fabric is dried

Advantages	Disadvantages
Large variety of colours Custom shades and tones possible Works on natural and synthetic fibres	Can fade over time Water and chemical use can harm environment Colour consistency may vary

Uses: Clothing, home textiles, accessories

Printing (Screen printing):

How it works:

1. A mesh screen stencil is created
2. To create multi-coloured products, the printer must make multiple stencils for each colour
3. The screen is then placed on the printing press
4. The item or garment being printed is laid down flat onto the printing board, underneath the screen
5. Ink is added to the top side of the screen, and a squeegee is used to pull the ink along the full length of the screen
6. The printed product then passes through a dryer, which 'cures' the ink and creates a smooth, colourfast finish

Advantages	Disadvantages
Low set up cost Can print onto a range of different surfaces Screens are rapidly made using emulsion so efficient for small production runs Screens are reusable so can be used for later batch runs	Slow process High cost per prodcut A different screen is required for each colour Colours can become inconsistent after many runs which leads to low qualitiy print

Uses: Posters, display boards, textile T-shirts

Pick and Place Assembly:

How it works:

1. Automated robotic arms pick up electronic components
2. They place components precisely onto a PCB (Printed Circuit Board)
3. Used in high-speed electronics manufacturing

Advantages	Disadvantages
Fast and highly accurate Handles very small components Reduces human error	High machinery cost Requires trained technicians Not suitable for small-scale production

Uses: Computers, phones, TVs, circuit boards

Flow Soldering:

How it works:

1. PCB is passed over a wave of molten solder
2. Solder bonds components to the board
3. Flux may be applied beforehand to prevent oxidation

Advantages	Disadvantages
Fast and efficient for mass production Good solder joints when set up correctly Can solder many joints at once	Thermal stress may damage components Requires precise machine calibration Setup is complex for small batches

Uses: Electronics manufacturing, consumer gadgets, PCBs

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