I recently got a ton of white oak (literally – 2500 lbs, 3ft+ trunk split by hand with a small axe and wedges, oh my aching back). I’ve been making a bunch of treens (wooden tableware) and doing some playing with color: black (with a vinegar/iron wash) and tan (household ammonia fuming) on sap wood (left of the line) and heart wood (right), all from the same tree.
- White oak branch, all sap wood, no color[ing].
- Ditto, but fumed for about a week.
- A sap wood scoop, blackened. The handle has two wash coats, the scoop has one. It has been sanded back (to adjust color), soaked in BLO and varnished.
- A spoon full of half & half. Two uniform coats, rinsed with water after the last coat had dried. No other changes. The heart wood turns much blacker.
Heart wood (to the right):
- One heart stick, one end blackened and the other fumed, then split lengthwise to see how deep the color change is. Not very.
- A “virgin” chunk of all quarter sawn heart. The medial rays are starting to show.
- Two half blackened chips: Top is heart, bottom is sap.
A note on the vinegar/iron wash: Put vinegar in a jar, add bits of iron (eg degreased steel wool, detritus from the grinding wheel, etc), let sit for while. A vile looking black solution forms, with scum on top. You can screen, but I didn’t. I apply with a tooth brush and sand when dry (to smooth the raised grain and remove undissolved iron bits). The color change is almost immediate. The solution keeps for months and months. Oh yeah, expect your hands to get just about as black and it doesn’t just wash off. Wear gloves.