Shaping Techniques Flashcards
Milling Machines
Used to remove material one layer at a time, can be set to produce a specific size or shape
Can be set to a specific cutting speed or depth
Also used to make a surface flat, and can be used to create a very accurate finish
Lathes are for turning materials
Wood lathes and engineers’ lathes are used for turning wood and metal, the material is held at one or both ends, then a bit or tool is pressed into the material as to cut it. Longer materials can be secured at both ends to prevent wobbling and damage to the material
3D printing
Addative process involves adding a material instead of taking it away. 3D printing works by printing layers of moltern plastic until the shape has been formed. You can design these via CAD machines and then use the 3D printre to create the model
Metal sheet presses
Press forming involves placing the metal between two moulds, and then applying large force to bend and shape the material.
The materials are usually in a malleable state when this happens.
Machines such as punches and die cutters do a similar job but to cut out areas instead of bend the metal
Casting
The process of casting involves moltern mterial being poured in to a mould and then being left to set before being removed from the mould.
Patterns are needed for this manufacturing process, an exact replica of the product is placed in material, and then removed (or vapourised in lost mould casting) before the moltern material is added.
Moulds are often made in two halves so they can be easily removed from the cast.
Die casting
Used to mould metals and thermoforming plastics
Material is melted and poured into the mould (or die) which is the shape of the product
The material is then left to solidify and can be removed from the mould
Some plastics can be cold-poured and solidifies as part of a chemical reaction
When the product is removed, you may have to trim the excess material off of the edges
Bending materials
Sheet metal folders are used to shape metal sheets of softer metals. The outline is marked on sheet metal that is then passed through the the machine, and bent at angles to create the desired shape, corners can then be joined by rivets or other techniques such as welding, souldering or brazing.
Laminating wood involves sticking thin layers of wood together and then gluing them in a Jig and left to solidify, so that they stay bent once they are removed from the jig. This has many uses such as rocking chairs and roof beams
Line bending is used to bend acrylic, it can be done with a line bender or a strip heater, the material is heated on 2 bars, once the plastic is soft, it can be bent and then allowed to cool and retain its shape
Heating metals for bending
Thicker metals needed to be heated, then bent and allowed to cool. This makes the material soft enough to bend, but may need to be repeated several times as the metal can become hard again, in a process known as work hardening.
