Sealing the Wood
Many problems can be encountered when applying oil and varnish finishes including uneven colour and darker coloration of end grain and soft areas. These problems are caused by the different amounts of finish absorbed into end-grain, flat-grain and softer wood. To ensure an even-looking finish ( little or no blotching) a sanding sealer is often used prior to the application of the finish.
To help control the color variation between end grain and side grain, sand the end grain with finer sandpaper than used on the side grain. Part of the reason for the difference in the color is that the end grain absorbs more finish. Sanding the end grain surface finer cuts down the amount of sealer being absorbed.
Sealing options: Shellac, commercial sanding sealers (cellulose-based dries faster) Deft semi-gloss lacquer (home brew or wiping varnishes and oils can be used over DEFT).
In the original documents, Russ discussed only Deft semi-gloss lacquer. At the time, Deft was the only brushing lacquer available. In 2009, he noted that others had become available, including an excellent brushing lacquer by Watco. These harden and seal the wood and accent the grain without discolouring the wood or leaving the muddy appearance that we get from sealers containing fillers. He used it also as a true low-no-gloss finish or as a base for Tung-varnish-turpentine blend.
Application of the DEFT finish:
1. Sand through 320 as per section 2.
2. Apply a heavy coat of Watco Liquid Finish Wax to accent and slightly raise the grain (also accents surface flaws).
3. Hand sand with 400-grit wet/dry sandpaper, with the lathe OFF, while the wax is still wet. Wipe the surface clean. Continue rubbing until any residual wax has dried – running the lathe helps.
4. With the lathe at 500 RPM, burnish the surface with a piece of grocery bag paper.
5. With the lathe OFF, apply a sloppy coat of DEFT semi-gloss lacquer. Russ uses soft mop-brush (see Craft Supplies Calalog) and sometimes a paper towel. The solids of the semi-gloss act as a grain filler.
6. Wait 1 minute, rotating the lathe occasionally by hand. Then remove all of the DEFT you can with soft paper towels, changing as they become wet and sticky. IF the surface becomes dry, dampen the towel with some thinner and continue rubbing.
7. With the lathe running at 500 RPM, burnish the surface with a clean paper towel (the speed warms the lacquer, helping it flow into the surface.)
With the lathe OFF lightly buff the surface with a gray ScotchBrite pad, fine bronze wool or 0000-steel wool to remove any traces of dried lacquer and circular marks on the surface.
8. If this is the final finish repeat steps 5 to 7 but don’t wait before wiping the surface in step 7. For a bit more gloss, polish the surface with Rottenstone, applied with Lemon oil or mineral oil and a felt pad (lemon oil finish is lemon scented mineral oil). Clean and polish with a soft cloth.
9. Apply 2 coats of a good quality paste wax.