We are now ready to apply a base for the French polish. This base is what is known as a "spit coat" or "wash coat" of shellac. The purpose is three-fold. First, it provides a bonding surface for the many microscopic layers of shellac that we will be applying to the guitar. Shellac is known as the best wood sealer because of itís high bonding properties. Second, it will help protect the inlays, purflings, and rosette from color contamination due to the oils and dyes in the back and sides of the guitar. Third, this base of shellac will combine with the pumice and natural wood dyes binding them into the pores of the wood. The first job will be to seal the purflings, bindings, and back strip. This will help to keep the oils and natural dyes in the wood from discoloring the inlay work. Cut an ample piece of t-shirt material into about a dozen 4" x 4" squares. Fold a 4" x 4" square of t-shirt material in half and then fold once more into quarters. With your squeeze bottle of mixed shellac, saturate the folded cloth pad until thoroughly wet (use no oil or alcohol).
Let's do the back of the guitar first. Drag the cloth pad over the purfling and bindings following the contour of the guitar. Do only one half of the guitar at a time. This should be done in a single pass without stopping and with no side-to-side movements. If done quickly and accurately, no color will be left in the inlays. Move to the other half of the guitar and turn the cloth over to a clean side, recharge the cloth with shellac and repeat. Having completed both halves of the guitar, refold your cloth to a clean quarter, add shellac, and seal the back strip in a single straight pass. Now refold your cloth pad to the last clean quarter and wet with shellac. In circular motions, wipe the "field" (unfinished areas of the back). By now your cloth pad is well contaminated with color from the wood. Dispose of the cloth and make a new one identical to the first. With a clean cloth, wipe each side of the heel joint with a single pass. Lay the guitar on itís side and seal the bindings and side purflings exactly in the same way as we did the back of the guitar. When the purflings are covered, use the cloth to cover the fields. Take care to fold the cloth to a clean quarter after each pass. Discard the color contaminated cloth as you fill in the field areas. Repeat the entire process for the other side of the guitar.
After completing the sides of the guitar, apply a spit coat to the rosette and the top purflings, refolding the cloth to a new quarter each time. With a clean cloth, coat the field areas of the top. You will have to make a new cloth each time you run out of clean quarters. We will repeat this process three times on the entire guitar. For each pass, we will refold our pad to a clean side. It's a good idea to always make a new folded cloth pad to do the top of the guitar to avoid color contamination.
It will take only about 15 or 20 minuets to spit coat the entire guitar. When the first spit coat is on, take time to examine the purflings. If, by chance, some color was drawn into the purflings you may want to take a small rubber block and sand the contaminated area using olive oil and 400 wet or dry sand paper. If you are adept at using scrapers, just scrape the discolored area and recoat with shellac. After letting the first spit coat dry for about half an hour, repeat the process. Each time that you apply the shellac the cloth pad will stay a bit cleaner. This is an indication that the purflings are becoming well sealed and a good base of shellac is being laid down. After applying three spit coats to the entire guitar, we will take a small artist's brush and again paint all of the purflings to provide additional protection for all of the inlay work since pumicing acts as an abrasive and can burn through the shellac to the purflings. In addition to painting the purflings, you may wish to apply a wash coat to the classical guitar machine slots as well.