Columbia PureBond
W O O D   W O R K S
October 2010   Vol. 9
Columbia Newsletter
Appearances Can Fool You!

One of the most common misconceptions regarding the use of wood for decorative purposes revolves around the anticipation that aesthetic appearance, especially color and grain, will be similar not only from piece to piece but also from log to log.  This perception is even greater for wood veneer cut by the same method such as plain sliced, quarter sliced, or rotary cut.  In order to avoid the headaches and heartaches that almost always result from this ingenuous line of thinking, let us now examine more reasonable prospects and how those may be achieved.

One picture (or sample) requires a thousands words
Veneer Samples
One of the major contributors to the confusion that leads to unmet expectations with respect to decorative wood panel products is the use of the photograph, artistic rendition, or sample. These examples have great educational value on a generic level, and I am certainly not opposed to them as long as everyone in the communication chain realizes the limitations they represent. It is important that we understand that a single photograph or small hand sample of a random piece of wood without accompanying words of edification is just not sufficient to create reasonable expectations for the overall appearance of a larger volume of wood for a given project. 

Likewise, artistic renditions, frequently ages old, used to illustrate a general grain appearance for a particular cutting method, again without a thorough explanation can not be considered a reliable means of predicting actual final appearance. The fact is that wood appearance can vary greatly from tree to tree, and it is similar only in a broad sense from within the same tree.  A single photograph or small hand sample of wood can offer the holder only the most general depiction of the look and feel of a given species. It tells you exactly what THAT particular piece of wood looks like, and absolutely NOTHING about the appearance of any additional wood of that species, even from the same tree. It positively does not and indeed can not provide a reasonable expectation for inherent variation in appearance that must be expected for any given application requiring wood from any source.
So, how can wood from the same tree look different?

Plywood ceiling
Birch Ceiling
Growth rates, drought, heavy
rainfall periods,wild fire, nutrition or lack thereof, competition for sunlight, freedom from competition from sunlight (thinning of the timber stand), disease, injury, insect infestation, fungal assault, impact of heavy limbs on grain configuration, and even location on slopes versus flat land are some, but definitely not all the possible contributors to variation in color and grain within a single tree. Carry that over to different trees of the same species, even from the same geographic location, and it should become clear that to expect every piece of face veneer to look the same is just not reasonable.
But all veneer cut by the same method should at least have the same grain appearance, right?

Sorry, but no.  Even cuts designed to produce a predictable grain pattern such as the straight alignment of the growth rings typically resulting from quarter slicing or rift cutting are subject to variation. Because the diameter of the growth rings are wider at the base of the tree and narrower further up from the stump, they will have a slight taper to them. In most cases this will produce a deviation from parallel to the edge of the board or sheet of veneer, a trait called slope.
Red Oak PS Book1
Red Oak PS Book
Red Oak PS Book 2
Red Oak PS Book
Additionally, due to stresses induced by limbs, growth on hillsides, interlocked grain, or growth interruptions caused by any number of contributors, the grain direction may abruptly change or flare in a different direction, particularly close to the stump, producing a characteristic called sweep due to its resemblance to the bend in a broom's straws as they flex across a floor. Plain slicing, the method most likely to produce cathedrals, that classic inverted "V" shape common to wood cut on the tangential plane, may sometimes produce rather straight grain absent of cathedrals (often sold as false rift or quarters), or at times, even the variegated uncontrolled look of rotary cutting.  


And please don't assume that a particular cutting method will NOT produce characteristics it is designed not to produce. True rift cut or quarter sliced veneer, actually quite rare in today's environment, is just as likely to produce slope and sweep as are false quarters, even though the perception is that it does not. The reality is that any excessive slope and sweep developed in true rift and quartered veneer must be downgraded, in effect greatly increasing the cost of the remaining veneer that meets a given specification.

Certainly the color should be the same color, shouldn't it?

This is one of the most perplexing characteristics of wood. The color of most sapwood is roughly similar, even across various species.  However, even within a given species, or even the same tree, there will be slight to significant color variation. For heartwood, color is so dissimilar between species that it is often used as a macro tool for identification, but within a given species the range of color of heartwood can vary wildly. The angle of the cut can exacerbate these color variations, as well.
Birch Nat C RC
Birch Natural RC
Birch SAP C RC
Birch SAP RC
Quite often I hear a complaint that the color of the face of a panel used for inserts in 5-part doors does not match that of the stiles and rails.  When you consider that dimension stock used for the frame are sawn from lumber that itself was sawn from a larger log before being kiln dried under lower heat over a gradual period, while veneer is traumatically sheared (sliced or peeled) from a log then introduced into a dryer at temperatures reaching 500 F or higher for relatively short periods of time, it should be easy to see that even process variations could contribute to color differences. Couple this with the fact that the two came from different trees, likely from different geographic regions, and it should become clear why there is usually some color difference. 

On a side note, I have observed on many occasions a stile and rail door with dark stiles and light rails to the point it looked like the two came from different parts of the world. However, a rotation of the frame 90 left or right resulted in the darker components suddenly becoming light, while the lighter components took on the darker appearance, even though all 4 components were cut from the same strip of stock. This clearly demonstrates how even the angle of the lighting can affect color.

So, does this mean I can't get wood that is close in color and grain for a given project?

Of course not! I frequently use a tongue-in-cheek expression to explain how one goes about ensuring their expectations are met:  "All I need are three things:  communication, time, and money."

What I mean by that from a serious perspective is:

1.    Communication. You need to tell us exactly what you need in terms we both understand. This includes how and where the panels will be used, the number of panels, whether they are to be used in proximity to each other, what grain appearance is needed, what color is expected, the type of matching within the panel, between components in the panel, or between different faces from the same log, glue type or fire rating that may be required, and any other specifics you can include. Here is where samples and photos come in.  What do the samples intend to show?  Are flitch samples from individual logs required? Can we use different logs as long as we select for color and grain? How close will the color and grain be if we choose that route? Can we produce samples that will show that reasonable range?  Who will agree to what the samples represent?  Where and under what conditions will control samples be retained?  The list could go on!

2.    Time. Remember, the more specific the requirements, the more likely the wood will have to be accumulated as faces that meet the specifications are encountered. Most veneer mills process thousands to millions of square feet weekly from many species and grades, so finding your specific look will take time, and the amount of time will depend on the extent of the specifications.

3.    Money. Please understand that the higher the expectation, the tighter the specification, and the more time, labor, sorting, packaging, care, raw material, and waste will be involved. These factors drive up the total cost, all commensurate, of course, with what is necessary for your given project. No one wants to charge an unfair price, but anyone qualified and willing to take the necessary measures to ensure your expectations are met should be able to collect fair pay for their efforts.  Whatever sting that may be felt from the sticker shock of some of these highly specialized products will quickly wane in the face of a breath taking finished appearance that makes your clients want to come back for more!

Parting Words

Wood is one of our most precious raw materials.  It adds beauty, warmth, protection, and comfort to our lives.  Here's to making sure we do our part to ensure it does all that in a way that meets our every expectation!

All my best!
Ang Signature
CFP Bold
In This Issue
Appearances Can Fool You!
One Picture Requires 1000 Words
Wood From the Same Tree Looks Different
What About Grain?
What About Color?
Can I Get Similar Veneers?
What is Wood Works?
Wood Works Newsletter
CFP University
This is a  service of CFP University and Ang Schramm to provide the Columbia community with tips, solutions and insights. Email Ang if you have ideas for more Wood Works subject matter. Feel free to forward to colleagues and customers that might benefit from the information.
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This information is offered in good faith for general purposes only. It is believed to be accurate and has been compiled from sources believed to be reliable. It is offered for your consideration, investigation, and verification.  Columbia Forest Products makes no warranty of any kind, expressed or implied, concerning the accuracy or completeness of the information and data herein. Furthermore, Columbia Forest Products will not be liable for claims relating to any party's use of, or reliance on information and data contained herein, regardless or whether it is claimed that the information and data are inaccurate, incomplete, or otherwise misleading.