Why Timber Defects Have No Place in the Trade
No matter how long you've been in the timber industry, you will have come across them. The little moments of hesitation, the tuts and winces as your stock is inspected, sometimes inch by inch, sometimes by just a cursory glance before they turn to you in despair and ask pointedly if you have any ‘clean’ timber.
The causes of such dissatisfaction? We know them as ‘defects’, although here are several reasons why we should not.
Following our recent article on timber sustainability, this article will cover several types of wood ‘features’ (rather than defects), how to deal with them, and suggestions on how our market audience might be gently nudged into thinking differently about what, initially, is what makes natural wood so inherently beautiful.
What are timber defects
Defects in timber are simply abnormalities or irregularities in wood. These irregularities occur because trees are living things and grow in an organic way; because of this, they are subject to factors that affect the appearance and texture of their timber, ranging from limb injuries to fungal wars. While these growth patterns, scars, marks and texture are present in every tree (with severe ones possibly calling the structural integrity and strength of the timber into question), these very defects contribute to the beauty and value of various precious woods and construction hardwoods, such as spalted ash and pippy oak.
Despite the damaging effect of referring to what makes wood inherently so wood-like as ‘defects’, the practice is widespread and showing few signs of slowing down. This is in spite of the efforts of timber traders across the world to educate their audiences that, as a natural material, wood is bound to feature aesthetic irregularities that should be celebrated, not shunned.
Why ‘clean’ timber is overrated
For one thing, customers after completely unmarked timber end up waiting for much longer! For another, while you can cut around defects and irregularities, this leads to a lot of wastage, which is never good and something which as an industry we try to limit as much as possible.
Happily, fixing wood defects is not only possible but often easy, especially with the advent of modern fillers and epoxy resin. All you need is a little time and patience.
Types of wood defects and how to deal with them
Some wood defects occur naturally as the tree grows and develops, some are scars sustained from injuries and natural forces, and yet more are the results of being a battle or feeding ground for beetles, birds and fungi.
Here some of the most common types of defects:
Warps and twists - Warps and twists in timber pose logistical problems to people who work with them, but can be fixed by milling
Knots - Dark, hard rings at the base of a severed branch. Usually consisting of small cracks, knots and knotholes, these are some of the simplest defects to fix, even if they are a hole that goes all the way through the board. These holes can be filled with epoxy or more adventurous materials, such as metal, to transform the knot into a feature.
Bark pockets and inclusions - A small, protruding piece of bark. These can be considered unsound but can equally be fixed in several ways. Clear all the bark to avoid inconsistencies in drying speeds and moisture content, then patch or sand the surface depending on your preferred aesthetic.
Splits - A rupture or separation in the wood that can make the entire piece of wood unsound. This is especially the case with ring shakes (or heart shakes), which run parallel to growth rings and are only detectable after drying.
Stains - A discolouration of any colour that can be caused by a variety of factors, including bacteria and fungi.
Rot - Soft, spongy areas of wood typically caused by fungi. Wood affected by dry rot is generally weaker or differs in colour to unaffected wood of the same species, although occasionally patterns such as spalting (which comes in all shapes and colours) are actually prized for their scattered beauty. Rot defects are difficult to deal with even for the most skilled woodworkers. According to Gary Goby, fixing them explicitly calls for epoxy thinned with acetone, left to cure for three days and repeated as necessary.
Burls - Deformed growth patterns caused by an injury sustained in the tree's early life. Typical burls include irregular projections, around which growth continues to occur, forming twists, swirls and knots in the wood fibre. These can result in patterns of spectacular beauty.
Insect damage - The tracks left by burrowing wood-destroying insects can be time-consuming to deal with but in minimal numbers do not typically affect the structural integrity of the wood (with the exception of termites). Again, epoxy that is thinned using a blowtorch may be used to fill all the small holes. Some coloured glues also dry well, ready to be sanded as desired.
Epoxy resin can and will fix many non-severe defects, filling up any cracks, indents and gaps where smoothness and strength is desired. Experienced woodworkers will sometimes use contrasting materials to address defects, choosing to celebrate the anomaly and draw out its beauty rather than hide it.
Some wood defects may also be sustained during the process of conversion, when timber is cut, milled or sawn for specific woodworking or construction purposes. These include torn or diagonal grain, chip marks, machine marks (burns, chips or gouges) and indentations of all shapes and sizes. These defects tend to be superficial and affect the appearance more than the integrity of the timber, with the exception of diagonal grain.
Final thoughts on wood defects
The presence of so-called ‘defects’ doesn't have to mean a piece of wood is unusable or in any way defective unless explicitly stated by your supplier. If you're willing to work with it, a small effort fixing imperfections can not only turn them into great focal points in your final product, but also support all our efforts in limiting timber waste as much as we can.
WL West Timber is a family-owned sawmill & timber merchant in West Sussex with over 155 years’ industry experience. We provide a wide range of air-dried oak and kiln-dried oak timber products and supplies. We also build and install custom projects for our customers.
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