Origins and Properties of Wood
What is the outer protective layer of a tree trunk called?
Bark
This is a light yellowish wood that is soft and easy to work with
Pine
What property makes metals good for electrical cables?
Electrical conductivity
Are plastics natural or artificial materials?
Artificial
What are the three actions used to work with wood?
Measuring/marking, bracing, sawing.
This is what is generally referred to as wood. It has a darker color and it the hardest part of the trunk.
This type of wood generally comes from evergreen trees. They are generally light and easy to work with.
Softwoods
Are metals good conductors or insulators?
These types of plastics can only be heated and moulded one time.
Thermostable plastics
What are the two types of saws?
Jigsaw/fretsaw and circular saw
This is the act of cutting the trunk of the tree so that it falls to the ground.
Felling
This wood is dark brown with a beautiful grain for which it is highly valued. It is semi heavy and hard but it can be easily worked.
Walnut
This is an alloy of copper and tin.
Bronze
Plastics are made up of large molecules called ______.
Polymers
Metals can be shaped by ______ing and ______ing.
machining and forming
The capacity of wood to absorb or expel moisture according to its location and climate
Hygroscopicity
A metal that is resistant to corrosion and oxidation
Noble metal
When heated to a certain temperature, this type of plastic can be moulded.
Thermoplastics.
______ means shaping plastic after it has been heated.
This means that the wood is easier to cut in the direction of the grains, or fibers.
Cleavability
Pressboard or fiberboard
Steel and cast iron are _____ metals.
What are the 3 types of thermostable plastics
PF, UP, UF (Polyphenois, polyester resins, urea-formaldehyde).
When drilling plastic and the diameter of the hole is more than ____ mm, it is a good idea to perform the operation in two or three steps.
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