What is wood grain?

Shop for Cabinet scrapers

Wood grain is the direction or pattern of fibres within the wood. When scraping, you generally need to follow the direction of the grain with the cabinet scraper to produce a smooth and even finish. Obtaining a smooth finish by scraping across the grain is very difficult, if not impossible.

The basic wood grain types are straight, spiral, wavy, irregular and interlocked.

The grain type can vary depending on the type of wood. For example, walnut and yew can be very complex and swirly. The grain type can also differ due to the unique way in which a particular tree has grown. 

Straight grain

This is when the fibres in the wood run in a single direction. Straight grain is produced from the growth of the tree so that the wood fibres run up and down the length of the wood.

Spiral grain

This type of grain is when the fibres within the wood twist and swirl. As the tree grows, the wood fibres twist, producing the spiral grain.

Wavy grain

This type of grain is produced when the direction of the wood fibres changes frequently.

Irregular grain

Wood grain is described as being irregular when it swirls and twists in random ways.

Interlocked grain

Trunks and branches put on a circle of growth each year. By cutting across the trunk and counting the rings you can find out how many years old the tree is – each ring counts for one year. Interlocked grain occurs when the growth of a trunk or branch twists in one direction for one or several years, followed by a year or more’s growth in the opposite direction. This has the effect of “locking in” different “cylinders” of spiral growth.

Why is the type of grain important?

The direction of the grain is simply the direction of the wood fibres. When using a cabinet scraper, you should follow the lines (wood fibres) as as far as possible. Change the direction of the scraper if the fibres turn in different directions.

Scraping with the grain makes the going easy and results in a clean and smooth finish. Going against the grain when scraping is heavy-going and can damage the wood, causing it to chip or tear out. 

When scraping the grain needs to be sloping upwards and away from the scraper. 

Avoid scraping when the grain is facing downwards towards the cutting edge otherwise the scraper will dig in too far, causing tear-out.

Scraping across the grain means the blade of the scraper will lie parallel to the fibres of the wood. This type of scraping does not always guarantee a clean and smooth surface.

Sometimes, not all fibres are removed and parallel grooves are left in the wood. This means the surface will need to be scraped again until it is even and smooth.

You need to follow the direction of the grain as far as possible, whether the grain is wavy, spiral, interlocked or irregular, or maybe a combination of these. For the best finish, no matter what type of grain it is, you should try to follow it, or risk damaging the surface of the workpiece.