Simulating walnut sapwood?

[Sam Marrocco]

I have a quantity of nice walnut that is nearly entirely heartwood. It seems that most woodworkers desire this even, darker wood for finishing. I, however, like the nice contrast of a streak of bright sapwood through the piece.

Can a someone suggest a method of adding a “splash” of sapwood type color through the existing dark walnut? I’m planning on finishing with a tiny bit of heavily diluted orange dye to warm it overall then an oil based topcoat.

[Jim Becker]

If the walnut you have was steamed, then there probably is some sapwood there, but steaming turns the whole thing the same ruddy brown. They do that to increase yields within the special rules for grading walnut. Non-steamed KD or air dried has a huge variation in color for black walnut. You could experiment with bleaching to see if you can get a sap-like edge, but I wasn't successful with that on a cherry piece I built a while back despite my best effort. So the best solution going forward would be when you are sourcing walnut for projects, make sure it's non-steamed.

As to finishing, I always do something to warm walnut up, especially since I typically use a waterborne topcoat for most projects. BLO and wax-free shellac is my typical first two steps. If you are using an oil based finish, then the warming is basically built in. Dying can enhance the effect, but be sure you absolutely test your process on scrap of the same walnut before you proceed on your actual project including at least one top coat as that can affect final color.

[John TenEyck]

If you send me those sap free boards, Sam, I'd be happy to replace them with ones having some great sap streaks in them.

My only suggestion would be to bleach those areas you want to look like sapwood. You have to use the 2 part bleach. Put it on with an artists brush only to the areas you want to bleach; repeat as needed. No clue if it will work, but I have seem people bleach walnut nearly white so it is possible.

John

[Jamie Buxton]

Two-part bleach may well do what you want. However, my experience is that it soaks into the wood to spread sideways, and wicks under masking tape. So keeping it exactly where you want it may be a challenge. I thought about, but never tried, the following sequence: mask the parts you want to bleach, then apply your finish to the part you want to keep unbleached, then remove the masking tape and apply bleach. The idea is that the finish on the part you want to keep unbleached will reject bleach better than masking tape.

[George Yetka]

I too like the natural contrast of the sapwood, especially with things lie end grain cutting boards

Somehow I ended up with an all sapwood piece of 6/4 x 10 x about 8' Ill trade ya. I don't think you'll ever be able to do anything and have it look natural. I would say depending on what your doing with it find away to add a contrasting wood.