All, IMHO, the finish is there for a very real purpose: to retard the passage of temp/humid, readily into the wood of the case/piano. The reason the "piano finish" was developed was with this reason in mind. The "piano finish" is the best within the "furniture" industry. Having said all that, I maintain that the finish needs to be something more than an Oil finish. I use Tung oil on my very expensive "Main Bench" and it serves me well, as it helps keep glue drips from sticking to the surface and can be rejuvenated from time to time. The rejuvenation process is the clue of why you should not use it for a piano finish. The process of Rejuvenation: Vigorously scrub with hot soapy water and scouring pad. Dry thoroughly, let set for 48 hours. Recoat with several lite coats of Tung Oil, wiping excess off after each application. After final coat, let set for 48hours before use. Well, there it is. You make the decision. IMHO Lacquer or Varnish are the only "proper" finishes. I wouldn't consider the Polyester finishes, because that stuff is extremely Carcinogenic when it's in a liquid state. (according to EPA) Regard, Joe Garrett, RPT, (Oregon)
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