Glossary of Finishing Terms
Manufacturers have a variety of names for what are essentially the same type of product. While there will always be something new or different on the market, the following descriptions may help you understand some key finishing terms.
* = Optional step in addition to application of sealer and specified topcoat(s).
Acrylic Lacquers
A high-quality clear system for finishing furniture, cabinets and a wide variety of wood and novelty items. They are water white in color with excellent nonyellowing qualities. Available in both solvent-type and water-reducible products.
*Aniline (Acid) Dyes
Synthetic colors which dissolve in the solvent for which they are formulated, i.e., water, alcohol, or oil. Many woodwork finishers refer to nearly all dyes as “aniline” even when this is not chemically true.
Binder
The part of the vehicle which does not evaporate. It binds the pigment particles together, stays on the surface, and forms the film of the finish.
*Bleaching
The chemical process used to remove color or whiten solid wood. This process may be used to lighten an extremely dark wood or to whiten a lighter colored wood. Most woods do not turn completely white when bleached.
Blushing
The whitish, cloudlike haze that occurs in fast-drying finishes, especially lacquer, when they are sprayed in very humid conditions. Blushing is most often due to moisture (water vapor) trapped in the film or to bits of resin precipitating out of solution.
Catalyst
Chemically, an ingredient added to a product to provide additional performance characteristics, such as faster drying, chemical resistance, or increased hardness of the finish.
Catalyzed Lacquer
A modified nitrocellulose-based coating with a catalyst added for enhanced performance.
Catalyzed Vinyl
A catalyzed coating with a vinyl resin base. Extremely tough and resistant to most chemicals.
Conversion Varnish
A catalyzed alkyd-based coating that is tough and resistant to household chemicals.
Coat
The final protective film of a finish system. There are various top coats with different properties.
Danish Oil
The general name for any number of wipe-on coatings based on tung or linseed oil, with solvents and resins added to enhance both drying and performance.
*Distressing
May be either of a mechanical or chemical nature to give special effects. *Filler: Used to advance the final build and smoothness of the finish. Filler may be neutral or a contrasting color to accent the pores. The use of filler alone may not completely fill all pores and is generally limited to horizontal surfaces of ring-porous woods such as elm, oak and ash. Close Grain species such as cherry, maple, birch and poplar seldom require filler. Few vertical surfaces benefit from the added labor of a filled finish.
*French Polish
A mixture of shellac and alcohol rubbed on with a cloth pad, usually to a high sheen.
*Glazing
An added step for achieving color uniformity and depth, and for highlighting the wood’s grain pattern. It also is used for tortoise shell, marble effect, or antiquing.
Gloss
Also referred to as sheen, a surface shininess or luster. *Hand-Rubbed Finish: The name given to an effect that is created by the manual process of applying a combination of abrasives and lubricants, after the final topcoat has dried, to smooth, flatten or dull that topcoat.
Metamerism
An apparent change in color when exposed to differing wavelengths of light; the human perception of color.
*Mirrored Polish Finish
Requires several steps of wet sanding, mechanical buffing, and polishing.
*NGR Stains
Non-grain-raising (NGR) stains are dye solutions that do not contain pigments. Spray application gives an overall transparent color to the wood, offering a high degree of clarity. Some fading may occur over time.
Orange Peel
The description of a coating which does not flow out smoothly; exhibiting the texture of an orange.
Overspray
The dry, pebble-like surface caused when sprayed finish begins to dry in the air before it hits the surface.
*Penetrating Dyes
Deep color, fast-drying stains often carried in solvents as a liquid or as a gel. Some water-soluble versions are available.
Penetrating Oil
An oil-based material designed to penetrate into the wood. It usually requires reapplication from time to time.
*Penetrating Oil Stains
Almost always a thin liquid mixture of oil and thinner with a dye added for color.
*Pickling
A white or light-colored pigment in either an oil or water vehicle. When wiped or brushed on to an open pore wood, the white stays in the pores and is usually wiped off the surface, either entirely or partially depending on the effect desired. Similar to the application of Filler.
*Pigmented Oil Stains
Almost always an oil-based liquid with pigments (not dyes) added.
Polyester
A very high-solids-content coating consisting of two components that require special care in handling and spraying. Leaves a deep, wet-looking, clear or colored finish. Limited repairability. Polyurethane: Usually a two-component system that may have a higher solids content than lacquers. Takes somewhat longer to dry than lacquer. A highly durable finish which, as a result, is very difficult to repair.
Sealers
Compounds that provide a sandable coating and a smooth surface for final topcoat application, provide system toughness and holdout, provide moisture resistance, and contribute to build and clarity.
*Shading
A technique that can be used to either highlight contrast, or create a more uniform appearance.
Shellac
A wood finish extracted from the secretions of an Asian insect; fast-drying and usually waxed for additional protection.
Solvent
A substance in which another substance is dissolved, forming a solution. Finish solvents include paint and lacquer thinner, mineral spirits, gum turpentine and denatured alcohol.
*Staining
One of the optional operations in wood finishing, producing the desired undertone color and complementing the wood with proper distribution of color, depth of color and clarity of grain. Selection of type of stain used is governed by desired aesthetic result.
Standard Lacquer
A nitrocellulose-based coating, usually without any additives, that dries by solvent evaporation. Generally easy to repair.
*Toners
Transparent or semitransparent colors used to even the tone of wood.
Varnish
An oil-based finish used to coat a surface with a hard, glossy film.
Vinyl Lacquers
Catalyzed lacquers made with a vinyl resin rather than a nitrocellulose base.
*Washcoats
Thin solutions applied as a barrier coat to wood. They are used prior to wiping stains for color uniformity. Shellac washcoats help finish materials adhere to resin-secreting woods.
*Water-Based Stains
Are made by adding hot water to universal tinting colors, then diluting that solution to the desired strength with cold water. They provide good grain clarity, but raise the grain and are slow to dry.
*Wiping stains
Thin pastes or thick liquids with pigment suspended in a solvent vehicle; applied and wiped with a cloth to remove excess stain.