Back to Course

JSS3: BASIC TECHNOLOGY - 1ST TERM

0% Complete
0/0 Steps
  1. Materials & Processing - Timber I | Week 1
    6 Topics
    |
    1 Quiz
  2. Materials & Processing - Timber II | Week 2
    4 Topics
    |
    1 Quiz
  3. Processing of Materials - Metals | Week 3
    5 Topics
    |
    1 Quiz
  4. Processing of Clay, Ceramics and Glass | Week 4
    5 Topics
    |
    1 Quiz
  5. Methods of Producing Plastics & Rubber | Week 5
    2 Topics
    |
    1 Quiz
  6. Drawing Practice - Isometric Drawing | Week 6
    4 Topics
    |
    1 Quiz
  7. Oblique Projection | Week 7
    2 Topics
    |
    1 Quiz
  8. Orthographic Projection | Week 8
    4 Topics
    |
    1 Quiz
  9. Perspective Drawing (One - Point Perspective Drawing) | Week 9
    4 Topics
    |
    1 Quiz



Lesson Progress
0% Complete

Topic Content:

  • Defects in Timber
    • Natural Defects
      • knots, shakes, etc.
    • Artificial Defects
      • bow, crook, cup, etc.

What are Timber Defects?

Timber defects are faults or irregularities in wood, caused either naturally or during the processing of the wood, which reduces the value or quality of the timber. Defects in timber can be Natural or Artificial.

Natural Defects:

This is a result of faults, or problems, that occur during the plantation period of timber, which later affect the durability, strength, quality, and market value of timber.

There are different types and they include;

1. Knots:

A knot is a defect that occurs at the branch of a tree. If a branch falls from a tree it may leave a knothole on the tree.

Tree knots

2. Shakes:

This is the complete separation of parts of a stem in a living tree. it occurs because of stress variation in the stem. There is the ring shake, cup shake, star shake, and heart shake.

Timber Shake

 

You are viewing an excerpt of this Topic. Subscribe Now to get Full Access to ALL this Subject's Topics and Quizzes for this Term!

Click on the button "Subscribe Now" below for Full Access!

Subscribe Now

Note: If you have Already Subscribed and you are seeing this message, it means you are logged out. Please Log In using the Login Button Below to Carry on Studying!

Responses

Your email address will not be published. Required fields are marked *

error: Alert: Content selection is disabled!!