Wood finishing

Wood finishing refers to the process of embellishing and/or protecting the surface. The process starts with surface preparation, either by sanding by hand (typically using a sanding block or power sander), scraping, or planing. Imperfections or nail holes on the surface may be filled using wood putty or pores may be filled using wood filler. Often, the wood's colour is changed by staining, bleaching, ammonia fuming and a number of other techniques. Some woods such as pine or cherry do not take stain evenly, resulting in "blotching". To avoid blotching, a barrier coat such as shellac or "wood conditioner" is applied before the stain. Gel stains are also used to avoid blotching.

Once the wood surface is prepared and stained, a number of coats of finish may be applied, often sanding between coats. Commonly used wood finishes include wax, shellac, drying oils (such as linseed oil or tung oil), lacquer, varnish, or paint. Other finishes called "oil finish" or "Danish Oil" are actually thin varnishes with a relatively large amount of oil and solvent. Water-based finishes can cause what is called "raising the grain" where surface fuzz emerges and requires sanding down.

Finally the surface may be polished or buffed using steel wool, pumice, rottenstone and other polishing or rubbing compounds depending on the shine desired. Often, a final coat of wax can be applied over the finish to add a slight amount of protection.

French polishing is not polishing as such, but a method of applying many thin coats of shellac using a rubbing pad, yielding a very fine glossy finish.

Different tools used to apply wood finishes include rags, rubbing pads, brushes, and spray guns. The processes involved and the terminology for the materials used are quite different in Britain than the processes and terms used in the USA. For instance, the process of replicating the look and feel of traditional French polished wood is more commonly done in the UK by "pulling over" precatalysed lacquer, within 24 hours of spraying, whereas in the US a "rubbed" finish is more common.

"'=Comparison of different clear finishes as used in America=

Wood varnish is a great way to make your work look nice. Choosing a clear finish for wood involves trade-offs between appearance, protection and durability, safety, ease of application, reversibility, and rubbing qualities. The following table compares the characteristics of different clear finishes. "Rubbing qualities", a term of art, indicates the ease with which the finish can be sanded between coats. It does not indicate a method of application such as brush or rag.

1 - accentuates visual properties due to differences in wood grain.

Automated Wood Finish Application

Manufacturers who mass produce products implement automated flatline finish systems that run a on a conveyor belt that first begin by being sanded, then dust is removed, and the wood finish is applied via spray gun. The material then can enter an oven or be sanded again depending on the manufacturer’s setup. The material can also be re-entered into the assembly line to apply another coat of finish depending on the manufacture.

References

* Michael Dresdner (1992). "The Woodfinishing Book". Taunton Press. ISBN 1-56158-037-6
* Bob Flexner (1994). "Understanding Wood Finishing: How to Select and Apply the Right Finish". Rodale Press ISBN 0-87596-566-0

See also

*Wood stain
*Refinishing
*Distressing

Wood Finishing Articles & Essays

* [http://www.diyinfo.org/wiki/Wood_Finishes DIYinfo.org's Wood Finishes Wiki] - A practical and extensive guide to finishing wood around the house
* [http://www.frenchpolishes.com/application_information/shellac_polish_application.htm Shellac Application] Article by Smith & Rodger
* [http://www.wood-finishes-direct.com/ Wood finishing products] - Project Guides and products available for wood finishing
* [http://www.homesteadfinishing.com/htdocs/ChoosingFinish.htm Choosing a Finish] Article by Jeff Jewitt
* [http://www.harpgallery.com/library/antiquefurniturefinishes.html Finishes on Antique Wood Furniture] - Many different finishes have been used to beautify and protect wood furniture through the centuries.
* [http://www.popularwoodworking.com/features/finish5.html Finishing for First-Timers] Article by Bob Flexner.
* [http://www.antiquing-furniture.com Painting Furniture] Learn how you can antique paint furniture
* [http://www.popularwoodworking.com/features/finish2.html Oil Finishes] Article by Bob Flexner on oil and oil-varnish blends
* [http://www.harpgallery.com/library/refinish.htm To Refinish or Not to Refinish (Antique Furniture)] - Collectors and experts have debated the question for many years.
* [http://www.furniturerestore.net/images/antiques_roadshow.pdf Antiques Roadshow and Refinishers] Refinishing considered harmful, or not?
* [http://www.thewoodshop.20m.com/finishing.htm Homeshop finishes that work] An article comparing and contrasting many popular finishes that can be applied by a DIY'er.
* [http://www.therealhobbithouse.com/essay2.htm To Refinish or not to Refinish?] "Hobbithouse Refinishing" -- An essay providing guidance for the antique furniture owner with regard to refinishing, restoration and preservation.
* [http://www.advancedequipmentsys.com/system1.html Advanced Equipment Systems] - Examples of Automated Finishing Systems