Product Design: In-depth knowledge and understanding
(K) APPROPRIATE SURFACE TREATMENTS AND FINISHES THAT CAN BE APPLIED FOR FUNCTIONAL AND AESTHETIC PURPOSES
Metal Surface Treatments
Video on Plastic Coating
Video on Enamelling
Video on Oil Finishing
Black steel is created through a mill process which involves rolling the steel at a high temperature (typically at a temperature over 1700° F), which is above the steel’s recrystallization temperature. When steel is above the recrystallization temperature, it can be shaped and formed easily, and the steel can be made in much larger sizes. Black steel is typically cheaper than bright drawn steel due to the fact that it is often manufactured without any delays in the process, and therefore the reheating of the steel is not required (as it is with bright drawn). When the steel cools off it will shrink slightly thus giving less control on the size and shape of the finished product when compared to bright drawn.
Uses: Black products like black steel bars are used in the welding and construction trades to make railroad tracks and I-beams, for example. Black steel is used in situations where precise shapes and tolerances are not required.
Metal Paint
Metal Primer
Paint easily flakes off of metal if applied directly to the surface. To prevent this,primer is used. It is like paint except it is designed to fill in the microscopic gaps in the material and stick to it. Applied over primer, paint adheres much better, for it easily bonds with the primer.
Surface treatments and finishes
Metal surface treatments and finishing processes: plastic coating, enamelling, oil finishing and black steel, paint and primer.
Plastic coating
Polythene is a common thermoplastic powder which is used for dip coating. Air is blown through the powder which makes it act like a liquid. Before dipping the metal is preheated to 180 degrees and it is then dipped in the fluidised powder and returned to the oven where it melts to form a smooth finish. It is used commercially for products such as dishwasher racks. It is often used on school projects for coat hooks and tool handles.
Surface treatments and finishes
Metal surface treatments and finishing processes: plastic coating, enamelling, oil finishing and black steel, paint and primer.
Enamelling
By Fowler&fowler (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
Vitreous enamel, also called porcelain enamel, is a material made by fusing powdered glass to a substrate by firing, usually between 750 and 850 °C . The powder melts, flows, and then hardens to a smooth, So in technical terms fired enamelware is an integrated layered composite of glass and metal. Enamelling is an old and widely adopted technology, for most of its history mainly used in jewelry and decorative art.
Surface treatments and finishes
Metal surface treatments and finishing processes: plastic coating, enamelling, oil finishing and black steel, paint and primer.
oil finishing and black steel,
Provides a simple protective coating against corrosion with layer of carbon formed over the surface of the steels
paint and primer
Primer coats generally seal a surface that will not receive the final paint directly. After the primer coat the final coat or coats are then applied. Paint generally work best when they are built up in many fine layer rather the fewer thick layers. This is when you see “runs” in paint when too much has been applied in one go.
Timber Surface Treatments
Wood Primer
Wood Sealer
Wood Varnish
Wood Stain
Wood Oil
Wood Polish
Wood Paint
A primer or undercoat is a preparatory coating put on before painting. Priming ensures better adhesion of paint to the surface, increases paint durability, and provides additional protection for the material being painted.
A sealer’s purpose is to "seal" the pores of the wood to give you a smooth, even surface for the top coats of varnish or lacquer. The sealer coat will also prevent the stain from bleeding into successive coats of finish materials.
A Varnish is a transparent, hard, protective finish or film. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent.
A Stain is defined as any transparent or translucent agent used to colour wood. Unlike paint, which has pigment suspended in a binder, the coloring agent in stain is a dye that is dissolved in liquid. Thus, the colour penetrates into the wood fibres, rather than resting on the surface like paint does.
Danish oil is a wood finishing oil, made of either tung oil or polymerized linseed oil.
It can provide a hard-wearing, water-resistant satin finish, or serve as a primer on bare wood before applying paint or varnish.
A Polish is used to protect against abrasions and gives your furniture a shiny appearance. While polish evaporates more quickly than wood wax, it is much easier to apply.
A Paint is not just used for protection of the wood but it is also used for its aesthetic value, sometimes as a way of matching other products in the house or garden.
Varnish is a transparent, hard, protective finish or film that is primarily used in wood finishing but also for other materials. Varnishes are also applied over wood stains as a final step to achieve a film for gloss and protection. Some products are marketed as a combined stain and varnish.
Wood Finishing How-To: Hand-Rubbed Tung Oil Varnish on Walnut
Varnishing
Staining
Preparing and painting wood
Self Finishing Nature of Plastics
Reasons To Texturing Plastic:
Examples of Thermoforming Plastics & Properties
Examples of Thermosetting Plastics & Properties