Chocolate packaging

MIG Welding

Metal Inner Gas

- Uses a electric curren and not a flame.

- The more ampage you use the more power u get

- The shoud is used to release gas and keep the metal clean

Safety

- Light can burn skin, retena

- Wear mask, light sensative

- Wear a Jacket and gloves

Prep

- Set ampage of welder for the thickness of metal

- Metal must be earthed in order for the circuit to complete itself

Metals

- becoming less commonly used
- Ferrous metals
- Non ferrous metals
- Non ferrous alloys

Ferrous metals
- Iron + carbon
- Rusts and oxidises

Non Ferrous metals
- Dont contain iron

Ferrous Alloy
- mix of metals that contain iron and carbon

Non Ferrous alloy
- Mix of metals that doesnt contain iron

Ferrous Metals
- Brittle, strong inpact strength

Mild Steel
- 0.3% carbon
-rusts easily, cant be hardened or tampered
- car bodies, screws

High-carbon Steel
- Harder than mild steel
- Difficult to work and rusts
- Drills and saws

Cast Iron
- Hard, brittle under compace
- Machine parts, break discs

Manufactured Board and Finishing Woods

Manufactured Boards
Sizes
8 foot x 4 foot, 2.42 metres x 1.22 metres

Plywood
- strong, layered up of different veneers (grains counteract)
- Mareen ply, water proof

MDF
- medium density fibreboard
-wood chippings mashed up and adhesive added and then compressed to form wood
- glue will cause blades to blunt
-cheap

Hardboard
- Usually used for filling gaps
- Weak fibres will separate if it gets wet
- Furniture blacks

Chipboard
-Kitchens, table
-Made of thicker chipping, glue and compressed
- Add coating to make it stronger

Blockboard
-Sections of timber joined together with 2 venners (aesthetic reasons)
- scraps used

Aeroply
- Designed to bend
- used in aeroplanes

Maplex
- "posh" mdf
- used for furniture
- easier to machine

ALL A JOINT MIX OF DIFFERENT MATERIALS!

Veneers- slice of wood
Slice veneering, cutting a thin layer of wood off a sqaured sheet of wood
Rotery veneer, wood is spun so when the blade is put in you get a thin sheer of veneer, like pulling paper off a toilet roll.


Finishing Woods
- water or oil based
- When you varnish you brush a plastic coat onto it
- Must finish when ANY material is used

Plyurethane Varnish
- Plastic based varnish
- Most common
- Glass satin

Wood Stain
- changes the colour
- also a varnish
- no varnish? add it!

Oils
- used for furniture

Preservatives
- Applied to timber outdoors

Paint
- to ismply apply colour to timber

Injected preservative (tranalise = processed)
- Processed= injected with tranalise
- Processed where wood is dried out
- Shed fencing
- Only injected into 5mm of walls of timber, on face
- Legthens life by 4x

Sand Casting

Process involves

-pouring molten meal into a prepared sand mould

-It is then left to solidify

- 2 holes are left either side of the mould

-1 hole is used to put the molten metal in and the other is to let out any gases

-once the mould has solified the sand is then removed and the cast is complete.

Sheet Metal Bending

Used to bend metals

Done using a Press Brake bending machine

Process involves

-Positoning a sheet of steel between a punch and V-shaped die. This punch then moves

down forcing the sheet to bend.

Plastic Extrusion

Step 1 - Thermoplastic powder is placed in the hopper; this powder then falls into the rotating

Achimedean screw. Which in turn pushed the material towards the heated section of the

extruder.

Step 2 - Heaters soften te plastic, forced threw the die by the rotating screw.

Step 3 - On exiting the die, pastic product is the cooled using a water jet.

Step 4 - Further along the transfer table, product is cut for the required legth.

Works like a childs plasticine toy, it pushed the plastic threw the holes

making a long tube. e.g piping