Episode 27 Fuming and Ebonizing

Fuming White Oak

On today's show I talk about changing the color of your wood through ammonia fuming and ebonizing with steel wool and vinegar. How the tannins do their job and how you can pump up the tannic acid with an additional coat to the wood.  Fuming White Oak produces an immediate darkening that will go all the way to black if exposed to ammonia long enough.  This is because of the high levels of tannic acid in White Oak.  Fuming White Oak just lets it do what it does naturally.  But other species with lower amounts of natural tannins may need some help and this is where the wash coat of tea or tannic acid can produce that same effect.  

Ebonizing uses Iron Acetate to react to the same tannins in the wood and create a similar effect to fuming.  Both are color fast treatments in that we are chemically changing the wood and not applying pigment to the wood.  Though if one were to go through the process of fuming White Oak or ebonizing it and then leave it outside exposed to the elements, even then it would eventually turn gray.

Protecting the Color of Wood

I then spend some time talking about keeping the color of wood when it is freshly milled.  All wood species undergo some kind of color change from freshly milled and will darken.  Exposed to the elements they will all turn a silvery gray color.  So how can you keep the Purpleheart purple and the Cocobolo rainbow colored?

Feedback

• Daisugi is a Japanese method of forestry that is similar to Coppicing discussed in episode 25.

emails

• Tommasso asks how to keep the color of Purpleheart or Walnut
• Shawn wonders whether loggers use the branches of trees they fell
• Matt wants to darken his wood and asks about ebonizing vs fuming and how they work.
• Jeremy wonders why the slab market is forecasted to dive.