![]() ![]() Lacquer is usually applied by spraying, so the process outlined here will focus on this method of application. Small changes are often initiated in the finishing process to either improve the process itself or the finish. For most craftsmen finish application is not a fixed, static process anyway, but is rather an ever-evolving, changing one. Rather than list and compare these variations to the entire process, we will outline – step by step – one specific process that will yield a very acceptable final finish, even for a first-time semi-skilled finisher. While these processes and finishing sequence are generally followed by most finishers, the details of the individual processes used in these factories or small shops can vary greatly – yet still yield the same highly desired thin, glass-like final finish on the completed instrument. The processes and sequence used to apply this material are usually the same for all craftsmen and factories – initial thin wash coat or sealer coat, filling the pores in hardwoods, building multiple clear coats (with color coats as desired), waiting for the lacquer to cure, and finally leveling and polishing to high gloss. Nitrocellulose lacquer has been used to finish musical instruments for decades. For these builders solvent-based lacquer is problematic. While most guitar builders prepare for or accept the space, equipment and safety requirements needed to spray lacquer effectively, there is a small but growing number of amateurs and professionals working to eliminate hazardous and toxic materials from their homes and shops. Strong ventilation of the spray mist while spraying, and of the curing instrument after spraying, is a must. Intermittent exposure to lacquer thinner vapors is a potential health risk, so it is necessary to wear a vapor mask and to avoid skin and eye contact as well when working with lacquer or lacquer thinner. The main drawback of lacquer thinner solvent based finishing is the hazardous nature of the evaporating solvent itself. This finishing system is also well supported with a full spectrum of pigments and dyes for coloring, as well as abundant pore filling, sealing, spraying, sanding and buffing products.Īlthough nitrocellulose lacquer can be applied by brush (with the addition of retarder ), it is best applied, as intended, with proper spray equipment and some kind of ventilation hood or booth. It is hard and durable, yet flexible, and can easily be buffed to a beautiful high gloss when cured. The resulting cured lacquer film is excellent for musical instruments. Solvent-based lacquer has been so extensively used in the guitar and furniture industries that all of its application and cured film properties are very well known and available. This feature makes the finishing process and any touch-up or repair easier and more controllable compared to most other finishing systems. Lacquer thinner solvent is strong enough to dissolve subsequent coatings together, and it can easily dissolve a cured lacquer finish as well. This strong solvent base is lacquer’s best advantage and primary disadvantage. Lacquer thinner is a volatile, “hot”, solvent containing a combination of hydrocarbon and chemical solvents – including naphtha, xylene, toluene, acetone, various ketones, and others. The lacquer film forms and cures as the solvent evaporates. This finishing material is made of nitrocellulose combined with other resins (to promote flexibility, durability, etc.) dissolved in lacquer thinner solvent. (Until very recently solvent-based nitrocellulose lacquer was simply referred to as “lacquer” in the musical instrument business.) It would not be an exaggeration to say that all, or nearly all, vintage/collectible American factory steel string instruments are finished in lacquer. musical instrument factories for steel string guitars, archtop guitars, banjos and mandolins since the 1920’s. Solvent-based nitrocellulose lacquer has been the dominant finish used by U.S. ![]()
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