Wood anatomy (3) softwood cutting planes

Summary

The video provides an in-depth explanation of the various axes and planes used to analyze the structure of a tree trunk. It introduces the longitudinal, radial, and tangential axes and describes how each axis relates to different planes, including longitudinal-radial, tangential-longitudinal, and transverse planes. The speaker explains how the wood's appearance changes depending on the direction from which it's viewed, highlighting the visibility of ray cells, particularly in softwood, and how these planes influence the patterns seen in wood, such as growth rings and ray flex.

Takeaways

• 😀 The tree trunk has three main axes: longitudinal, radial, and tangential.
• 😀 The longitudinal axis is the growth direction of the tree and is vertical.
• 😀 The radial axis is horizontal and runs outward from the tree's center.
• 😀 The tangential axis is perpendicular to the radial axis and runs along the surface of the tree.
• 😀 Each axis can be used to form two-dimensional planes, such as the longitudinal-radial plane and tangential-longitudinal plane.
• 😀 A longitudinal-radial plane cuts through the tree along its growth direction and radial direction, showing growth rings.
• 😀 A tangential-longitudinal plane cuts along the tangential and longitudinal directions, with the wood appearance varying based on this plane.
• 😀 A transverse plane looks at the wood from the top, showing the growth rings in a circular pattern.
• 😀 The visibility of ray cells in the wood depends on the type of wood: softwoods have less visible ray cells.
• 😀 Softwood typically shows very little patterning in ray cells, often referred to as ray flex.

Q & A

What are the three main axes in a tree trunk's structure?

The three main axes are the longitudinal axis (growth direction), the radial axis (coming out in a direction perpendicular to the growth rings), and the tangential axis (tangent to the radius).

What is the longitudinal axis of a tree trunk?

The longitudinal axis is the vertical axis that follows the growth direction of the tree, running from the base to the top.

How is the radial axis defined in the context of a tree trunk?

The radial axis refers to the axis that comes out from the center of the tree trunk, perpendicular to the growth rings, essentially representing the radius of the tree's cross-section.

What is the tangential axis in a tree trunk?

The tangential axis is tangent to the radial axis, running along the circumference of the growth rings, perpendicular to both the radial and longitudinal axes.

What is a longitudinal radial plane in a tree trunk?

A longitudinal radial plane is a two-dimensional plane formed by the longitudinal axis and the radial axis, creating a flat section that cuts through the tree trunk vertically along the growth direction and radius.

What does a tangential plane look like in a tree trunk?

A tangential plane is a two-dimensional plane formed by the tangential axis and the longitudinal axis. It cuts through the tree trunk in a way that focuses on the growth rings, showing a curved appearance.

What is the appearance of a transverse plane in a tree trunk?

A transverse plane cuts through the tree perpendicular to the growth rings, showing a cross-section that displays the growth rings from the top.

How does wood appear when cut along the radial longitudinal plane?

When cut along the radial longitudinal plane, the wood shows the growth rings running in a radial direction, with ray cells running perpendicular to the growth rings, often visible depending on the wood type.

What is the difference between ray cells in softwood and hardwood?

In softwood, ray cells are less visible and tend to be uniserate (single row of cells). In hardwood, ray cells are often more prominent and can form multi-serate structures (multiple rows of cells).

What does wood look like when viewed along the tangential longitudinal plane?

Wood cut along the tangential longitudinal plane will show the growth rings in a curved pattern, with ray cells less visible in softwood, resulting in a more uniform texture.