here is a link to the knifenetwork discussion after a hammer-in at Larry Harley's a couple years ago. there are quite a few more links provided in the thread.

staining figured wood

Had a look at that discussion thread and it is quite different from what I was given as a recipe.
Like I said, I'll share the whole process later.

One big thing with the guy's recipe he's given on that link- the addition of the steel wool means two separate things are going on. One is the acid oxidation of the wood (darkening it) by the HNO3, the other is the creation of a ferro (iron) - tannate complex with the tannins in the wood and the steel wool. It will be more successful with tannin-rich woods such as oak, but much less so with boxwood.

Steel wool can be used as a mordant for dyeing, but that doesn't seem to be what's going on here.

just a few random thoughts...

I am not up on acid staining of wood. I have seen several pictures of Alan Longmire's Maple hawk handles. They have the nicest, most vivid curls and accents of any Maple handles that I have seen.

I have often wondered how Alan achieved this effect.

I copied this for later use.GRIN. THANKS..

Chuck

My take on the acid is it turns the sugars in the wood to carbon. heating with a hair dryer accelerates the process. i have tried the recipe a couple times with muriatic acid and had poor results. i have better luck with aniline dyes thinned with alcohol. working with a low dye content and applying more coats till i get the color depth i am looking for. there are some types of opal that are saturated with a heavy sugar solution and placed into acid to make them appear like black opal.

As I recall from my days in the chemistry lab, nitric acid (HNO3) reacts with proteins to make a golden brown stain. I'd say that is what is happening with the nice figured maple enhancements.

My professors always had a field day examining our hands for evidence of our sloppy lab techniques. It didn't matter how fast you could rinse the nitric acid off your fingers, it was too late - the stains were already there.

PS - this golden brown stain only works with nitric acid.