Replies

1. 
   P3Driver | Jan 15, 2007 04:49am | #1

   In the October 06 issue of Woodworker's Journal, Michael Dresdner answers this question this way; "Coatings that cure through solvent evaporation, such as shellac, lacquer and water based coatings, will all work.  Of these, an exterior water based polyurethane is...best."

      He also says that for a more durable finish, "Seal the case with one coat of Zinsser SealCoat, a dewaxed shellac based sealler that is compatible under oils and will act as a barrier to the antioxidant (naturally contained in Cocobolo).  When the SealCoat is dry, apply serveral coats of exterior oil-based polyurethane."

2. 
   Rich14 | Jan 15, 2007 05:11am | #2

   Roth, The best finish for true rosewoods like cocobolo and other oily woods is lacquer. Cocobolo can be particularly difficult, even more so than brazilian rosewood. You CAN use shellac as a sealer, but I've had the best results with vinyl sanding sealer paired with the same manufacturer's matching lacquer product (either nitrocellulose or CAB Acrylic. Nitro imparts an amber tint and yellows with age, CAB Acrylic is water white and will not yellow. There are many good products, but I have used Sherwyn Williams most. Using a pore filler is a personal choice. I like some pieces finished with the pore structure open, others completely filled so the surface can be rubbed out to a glass-like final appearance. Pore filler is applied after sealing. I stain it "walnut" with dye stain (any dark, slightly-reddish brown tone is good). Cocobolo polishes like stone and deserves really careful preparation. I final sand to 320 or 400 if I am going to keep the finish thin, which I like to do. The finish is then rubbed out all the way through automotive rubbing compound (red) then polishing compound (white) and swirl remover. If the finish is going to be thicker, it's not necessary to final sand much past 220-320. Then, final rubout is the same. Unfortunately, it's hard to predict which samples of cocobolo will retain their fresh-sanded vivid color and which will turn uniformly dark brown over time. Rich