Material and Manufacturing Videos Growing collection of videos giving insight into the world of manufacturing

Contents:

• Ceramics
• Composites
• Silicone Rubber
• Thermoplastics
• Products (multiple processes)

Ceramics

Stages of clay

Clay throwing (on a potter's wheel)

Handbuilding

Commercial Slipcasting

Sculpting

Composites

Fibreglassing process (hand-laminating)

Large-scale fibreglassing (e.g. boat-building)

Vacuum-bagging process used on GRP

Solid Surfaces (e.g. Corian, Hi Macs etc)

Concrete and Gypsum

Silicone rubber

Silicone (not to be confused with the element 'silicon'), is a synthetic rubber used widely throughout the world. Being a thermoset and synthetic - it's curing is not reversible and it cannot be recycled. There are many types of silicone rubber, and some types require processing in industrial settings (not available at NTU). Here are some terms that may crop up during your research:

'RTV' - stands for 'room temperature vulcanising'. RTV-1 silicones have a single component (see video below for more details). RTV-2 silicones have 2 components that need to be mixed together. Both types of RTV cure into a rubber at room temperature and do not require any additional heat or pressure. An example of an RTV-1 silicone would be silicone bathroom sealant. Various RTV-2 silicones are stocked in Alternative Materials. Speak to Emily if you'd like to see samples of these.

'HTV' - stands for 'high temperature vulcanising'. Is used to describe any rubber that needs heat in order to reach full cure. Example of HTV's include: HCR and LSR (see below)

'HCR'- stands for 'high consistency rubber'. HCR is one type of HTV silicone with a thick gum-like consistency that needs heat in order to reach it's full cure and become the final rubber. It is often used to create maxillofacial and body prostheses. It is too thick to injection-mould, so it is often pressed into moulds. Tougher, more durable products can be made with HCR than from RTV-2's or LSR's. See video

'LSR' - stands for 'liquid silicone rubber'. This can be confusing because many RTV-2 silicone are also liquid in their consistency. LSR is often injection-molded to produce large volumes of rubber parts for commercial products and the medical industry. It needs heat and pressure to fully cure, so takes longer to injection-mould than thermoplastics. A common example of an LSR product would be a silicone ice cube mould.

Catalyst types: Platinum, Tin, Peroxide, Acetoxy or Oxime - Silicone rubber may be cured by a platinum-based addition cure system, a tin-based condensation cure system, a peroxide cure system, or an oxime cure system. For the platinum-based cure system, the curing process can be accelerated by adding heat or pressure. Catalyst type does not dictate a silicone's final properties such as colour, shore hardness or tear strength. Some types might lend themselves to certain manufacturing processes over others. Some catalyst types are not exclusive to types of silicone, for instance there are both platinum-curing HCR's and peroxide-curing HCR's, but curing by way or acetoxy or oxime are exclusive to RTV-1 (1 component) silicones.

How colour is mixed into HCR

LSR injection moulding process

Thermoplastics

Thermoplastics: overview

Overview of thermoplastic forming processes

Extruded Acrylic

Cast Acrylic

No commentary on this video - molten acrylic is poured between 2 plates of glass. Beforehand, the plates of glass are sealed round the edge with dictate the thickness of the final sheet.

Other cast acrylic processes (embedding, sandblasting, external and internal laser etching)

Vacuum-forming

Blow-moulding

Strip heating (bending plastic along a straight line)

Rotocasting / Rotational moulding

Compression moulding

Vinyl records

Youtube short of making process

Brothers Make - Guide to reforming HDPE (full process tips)

Products (multiple processes)

Trainers (traditionally-made)

Crocs (one-material designs)

3D-printed shoes