Tgif: Three Things: Three Things That Add Color - Tuesday, May 15, 2018

[kmealy]

Three things  that affect the finished color of a project

 

1. The wood.  You would not expect the same resulting color if you applied the same products to, say, pine, poplar, walnut, maple, cherry, or white oak.   Each wood will impart not only its own natural color, but the grain and porosity of the wood can affect how it  absorbs the upper layers.   I have applied exactly the same stain to ash and red oak, that look very similar in the rough (ring porous woods) and on red oak it comes out a light brown and on ash, a light yellow. 

 

2. The colorant.  The dyes and/or pigments in a stain, glaze or toner will obviously impact the resulting color.   And it may interact with the underlying wood.  For example, if you add a raw umber color, normally a darkish green to a wood like cherry with a lot of natural red, they will neutralize each other and come up with more of a brown result.   If you put raw umber on maple, you are going to see more of that greenish color.

 

3. The finish.   All finishes can add (or omit) color.  Waterborne finishes and lacquers called "water-white" add virtually no color.  These are great if you don't want added color, for example over a pickled finish.  On the other hand, they can look like the finish is washed out.   Shellac comes in different grades from super blond, blonde, lemon, orange and garnet.  Sometimes they are called light amber, amber, natural, or whatever just to confuse us.  Varnishes (oil-based) generally have an amber color.  Exactly what depends on the mix of which oil and which resin.    Soy-alkyd, linseed-urethane, or tung-phenolic are the common combinations and vary from light to dark amber, respectively.

 

So that is why when you are doing test boards on scrap, you need to use the same wood, the same colorant, and the same finish, all the way to completion.

 

Also, the color you get on day one may not the color 10 years down the road.  Woods tend to change color - cherry darkens, walnut lightens, and maple ambers.   Dyes and pigments tend to fade in light, dyes usually more so.  And if you have a colorant with two or more ingredients, one of them might change faster than the others. So an amber might fade to an orange.   On one hand you have the woods going one way and perhaps the colorants going the other, each at their own rate.

[Fred W. Hargis Jr]

It seems to me that the most overlooked point(s) are the ones mentioned in the last paragraph. Folks have talked about how they spent hours trying to color match cherry pieces, I've done that as well...only to have it come out looking like different pieces of wood after a couple of years.

[kmealy]

Just pull off an escutcheon from an old piece and see how it has changed with exposure to UV over the years.

[lew]

Thanks for another great post!