In our effort to explain the many influences on lumber color variation and how it influences the elusive color-matching aim, we’ll begin by explaining how grain and sunlight affect lumber color.
Natural Grain Variations
As grain flows over knots or moves to provide stability to a tree in its fight against natural powers, an amazing network of fluid patterns emerges, making each tree — and each board cut from that tree — as unique as a human fingerprint. Faster growing periods will create closely grouped growth rings and greater density, while slower growing periods will lead to more widely spread rings and less dense parts of a tree; often, both types can be found in a single tree, varying annually. Figured grain can be caused by many factors, leading to curvy grain that can be exposed on the face to display curly and even quilted designs.
Grain Via Milling
In addition to the grain naturally produced by the tree itself, humans can influence how grain is displayed by the way in which each board is sawn from a log. A board sawn from the center of a tree will display markedly different coloring than one sawn from the periphery. No matter how a board is sawn, the ends will appear darker than the face.
The kind of parallel grain many woodworkers highly prize can be achieved by milling Rift or Quarter-sawn boards; however, even with those methods, flecks of denser fibers (referred to as Medullary Rays) can show up on the face. Often, parallel grain can make a board appear darker overall, while other times a striped appearance is the result. Quartersawn boards are also infamously prone to tear-out during planing due to the direction of the grain, causing yet another method in which the color of a board can be influenced.
Exposure to the Elements
If you’ve spent any amount of time outdoors, especially over an extended period of time, you realize how harsh the elements can be. Just as our skin can easily become discolored or dried out due to exposure to the sun, lumber is greatly affected by its rays. Over time, any species of lumber will fade to a silvery gray. While color change occurs gradually, and some color variation appears randomly, the highest degree of change occurs when a board is freshly milled.
A freshly cut or planed board has surfaces being exposed to air for the first time; as a result, they begin the process of dumping any extraneous moisture. Chemical changes also take place, leading to color change. Over time, the disparity in color among boards — however extreme they may be at first — will mellow, creating a more homogenous effect. In order to begin the mellowing process before installation, you can simply allow your boards to lay out in the sun for a time; just make sure they’re positioned carefully, since wood can get “tan lines” just like people!
Continue with Part 3.
Read the Series
• Why Color-Matching Lumber Is Nearly Impossible, Part 1
• Why Color-Matching Lumber Is Nearly Impossible, Part 2
• Why Color-Matching Lumber Is Nearly Impossible, Part 3
• Why Color-Matching Lumber Is Nearly Impossible, Part 4
J. Gibson McIlvain Company
Since 1798, when Hugh McIlvain established a lumber business near Philadelphia, the McIlvain family has been immersed in the premium import and domestic lumber industry. With its headquarters located just outside of Baltimore, the J. Gibson McIlvain Company (www.mcilvain.com) is one of the largest U.S. importers of exotic woods.
As an active supporter of sustainable lumber practices, the J. Gibson McIlvain Company has provided fine lumber for notable projects throughout the world, including the White House, Capitol building, Supreme Court, and the Smithsonian museums.
Contact a sales representative at J. Gibson McIlvain today by calling toll free (800) 638-9100.