Seal knots with dewaxed shellac before applying a top coat. Brush on two coats of a two-pound cut. Without this seal coat, small bubbles may appear in your finish above the knots. The bubbles are called “bleed-through,” and they’re caused by oils in the knots reacting with the finish. Pine knots are the worst offenders. Shellac is the most effective barrier to these oils. When its wax has been removed, shellac can be used under any finish.
(Note: Source information may have changed since the original publication date.)
Woodworker’s Supply, woodworker.com, 800-645-9292, Wizard Tint (concentrated dye), 2 oz., #913-567 medium walnut, #913-588 ebony, $17 each; System Three slow-set epoxy #119-423 resin, 1 qt., $26, #119-435 #2 slow-set hardener, 1 pt., $17.
WoodFinishingSupplies.com, woodfinishingsupplies.com, 866-548-1677, Zinsser’s SealCoat shellac (dewaxed, 2-lb. cut), $8/qt.
This story originally appeared in American Woodworker March 2004, issue #106.
March 2004, issue #106
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