Chapter 2 - Finishes and Finishing Processes Flashcards
Self-finishing
The term given to a material that has an acceptable finish after processing. i.e. plastics with well finished moulds, stainless steel, copper, brass and some woods.
Self-coloured
The term given to a material that has an acceptable colour after processing. Plastics have colour added prior to processing so can be considered self-coloured
Applied finish
Refers to coatings that are applied to the surface of the material for protection and/or decoration
Burr
A rough edge created following a cutting process
De-burring
The process of removing burrs from the edge of material that has been cut.
Varnish
A hard transparent finish that is applied to wood, e.g. yacht varnish is applied to products that are intended for external use; while synthetic varnishes such as polyurethane varnishes are used internally.
Natural barriers
Protective layers close to the surface of a material that protects the material from corrosion, decay or degradation. E.g. the oxide layer that is present on non-corrosive metals such as stainless steel or copper.
Blueing
A method of finishing steel products that involves heating the product to around 300 degrees Celsius, followed by quenching in oil. It is the oil that gives the material a characteristic blue finish.
Electroplating
The use of the process of electrolysis to coat a base metal with a second more decorative material. E.g. silver plated cutlery.
Anodising
An electrochemical process that is used to make the surface of aluminium more durable. In addition, coloured dyes can be added for a decorative finish..
Painting
The process of applying paints. E.g. brush painting, spray painting. The term applies to all types of paint including oil based, gloss paints, acrylic paints etc.
Electrostatic Spray painting
An electro static charge is set up between the object to be painted and paint particles making a secure bond between paint, material and product surface.
Powder coating
This process uses an electrostatic charge to coat the metal product. Once coated, the product is baked in an oven to produce a smooth high gloss finish
Plastic dip coating
A method of finishing a metal based component. The component is heated to above the softening point of the polymer, which is in the form of a fine powder, then dipped into the polymer. The polymer adheres to the heated metal which begins to cool and so the polymer solidifies into a protective layer.
Wood preservative
Applied to timbers that are exposed to general weather conditions and which do not have any other means of protection. Preservatives prevent moisture entering the structure of the material, thereby reducing the risk of wet rot.
