Adhesives and Fixings Flashcards
Polyvinyl acetate (PVA)
Water based adhesive used to bond most woods and wood-based materials together
Fast drying and high bond strength
Not usually waterproof - the glue itself is water soluble
Can be used for furniture joints
Contact adhesive
Uses for bonding large areas such as sheet material
Can be used to join the same and different materials together
The two surfaces to be joined are coated in contact adhesive and left for approx 10 mins or until the adhesive feels ‘tacky’. Then on contact with the other surface, adhesion is instant
UV hardening adhesive
A clear liquid that quickly ‘cures’ to form a bond when exposed to UV light
Contains a photo initiator - as it absorbs UV light it begins to cure and set a solid bond
Can be used to join metal, glass and polymer
Excess adhesive can be wiped away with a cloth prior to UV exposure, thus giving a solid and clean joint
Used in dentistry - it allows glue for braces to cure quickly
Solvent cement
Most commonly a clear liquid called dichloromethane used to join polymers such as acrylic, ABS and PVC
Softens the surface of the polymers to be joined, allowing them to fuse together
Can be used in the plumbing industry to bond non-pressure pipes made from ABS or PVC together
Epoxy resin
Comes in two parts: resin and hardener
Used to join different materials together e.g. Timber to metal, metal to polymer, polymer to timber
Equal amounts of resin and hardener are mixed to form the adhesive, which is then left to set
High strength join
Electrical insulator
Chemical and solvent resistance
Jigs and fixtures
Used to ensure that parts or components can be made repeatedly, more quickly and accurately
A jig both holds the work and guides a tool, eliminating the need to repeatedly mark out the workpieces
A fixture is something that holds work in a given position while a manufacturing process takes place
Adhesives and fixings examples
PVA - polyvinyl acetate
Contact adhesive
UV hardening adhesive
Solvent cement
Epoxy resin
