4.1. Natural Defects

Try these first

1. 1.

   What is a knot in wood?

   Hint

   Think about where branches grow.

2. 2.

   Name one type of shake.

   Hint

   Consider the pattern around the pith.

3. 3.

   What are knots primarily caused by?

   • Insect damage
   • Branch growth
   • Improper seasoning

   Hint

   Think of where branches normally attach.

4. 4.

   True or False: Loose knots are more desirable than tight knots.

   • True
   • False

   Hint

   Consider the stability of the wood.

5. 5.

   Given a 2x4 beam containing tight knots and loose knots, calculate which one would be preferable for a load-bearing structure and why.

   Hint

   Consider how knots affect strength.

6. 6.

   Assess a piece of wood that has both a star shake and a heart shake. Discuss how these shakes could affect the wood's use in construction.

   Hint

   Evaluate which shake is more severe in terms of potential failure.