Why You Should Purchase Wood Without Knots
When selecting wood for any project, particularly pine and other woods known to have knots, it is important to select pieces that have no visible knots.
12/09/2023
Any type of wood that often has knots, such as engineered pine and laminated pine shelving, should be avoided at all costs, whether you are using that wood to make furniture or decor accessories, or you are using it for exterior purposes such as decking. There are many reasons why you want to avoid wood with knots and here are just a few of the more important ones:
What Are Knots in Wood?
Visible as rings in wood that the grain flows around, knots are formed when a branch falls off from the tree and the tree has continued to grow in height and girth, encompassing the knot. When the tree is cut down and used for lumber, the knots become part of the cut timber that eventually ends up planed (PAR) at a timber merchant or hardware store, made into laminated pine shelving products, or sized for particular use such as decking planks, fencing, etc.
After the wood has been kiln-dried and treated for timber merchants and hardware stores, the knots differ in shape and size, as well as colour, depending on the size of a branch that was originally connected to the tree. Some knots are brownish in colour and still look wet, others are dark brown to back and hard.
Why are knots in wood bad?
Knots are responsible for weakening the strength of a piece of wood and if the piece you are making needs to bear weight, a piece with a knot would not be suitable. Structural timber is selected according to the density of the wood grain and lack of knots to ensure maximum strength and integrity.
Unless you are specifically looking for wood to bring a rustic, country, or cottage feel or are crafting a piece using expensive hardwoods that have knots, consider that these add a distinctive finish to furniture and fittings.
What can you do about knots in wood?
First and foremost, try to avoid buying any wood that has knots as there exists a possibility that as the wood expands and contracts or even dries out a little, the knots may fall out and leave behind a hole in the wood. Not something you want if you have spent a lot of time and money on making a piece. If you have no choice but to purchase a piece of wood that has a knot here are some tips to keep in mind:
- Save this piece for a project that has a rustic style so that the knot becomes a feature rather than a failure. Keep in mind the positioning and consider that the knot may fall out in the future.
- Use epoxy resin to fix any visible gaps around the knot. While this may not fully prevent the knot from falling out it will provide stability of the knot within the surrounding wood.
- Use superglue (cyanoacrylate). Because superglue is super runny it is perfect for running over a wood knot and allowing it to soak into any gaps around the knot and lessen the chance of a knot falling out.
- Purchase a Wood Repair Knot Filler Gun and coloured Thermelt Filler Sticks for small or large knots.
