Hide sapwood with dye
I'm working with a wide piece of walnut that has sapwood on one edge. Is there a good way to stain the sapwood to match the heartwood?
—Ken Johnson, Lancaster, Pa.
Use dye instead of stain to equalize heartwood and sapwood color differences, Ken. Unlike most stains, dye doesn't have pigments that settle into wood pores, thus emphasizing them. You can easily lighten or darken dye for a close color match. For the walnut part shown above, we used TransTint dark walnut dye (Woodcraft no. 128485, $17, 800/225-1153 or woodcraft.com), but you also can use brown mahogany (no. 819064). Mix 1 teaspoon of dye in 1 cup of water, then test your dye color on sanded pieces of scrap sapwood. Add water or dye to the mix to lighten or darken the color until you get a match close to the color of heartwood moistened with a damp cloth. Don't worry about making a perfect color match; wood naturally has slight color variations.
Now, on your workpiece, moisten the adjoining heartwood to preview the color the wood will turn once it's finished. This also blocks the dye from bleeding into the heartwood. Then moisten a towel with dye and press out the excess. Wipe the dye onto the sapwood, working with the grain. To blend the edges of the dyed area with the heartwood, wipe them with a moist cloth. A light sanding with 220-grit abrasive will knock down raised grain.