17. Wood processes

Question 1

What can wood processes be grouped into?

Answer 1

• addition
• forming
• wasting

Question 2

What are the addition processes?

Answer 2

• traditional wood joints
  
  • dovetail
  • comb
  • housing joint
  • half lap
  • dowel joint
  • mortise and tenon joint
• component joining
  
  • knock-down (KD) fittings
  • modesty blocks
  • barrel nuts and bolts
  • cam-lock connectors
  • wood screws
  • coach bolts

Question 3

What is a dovetail joint?

Answer 3

• have multi-directional strength
• once glued, impossible to pull apart
• can be cut by hand using a dovetail saw
• can be machined with a router and jig, requiring much less skill

Question 4

What is a dovetail joint used for?

Answer 4

drawers

Question 5

What is a comb joint?

Answer 5

• two pieces being joined interlock
• two pieces create an increased gluing surface area
• very strong

Question 6

What are comb joints used for?

Answer 6

box construction

Question 7

What is a housing joint?

Answer 7

• groove cut across one piece of timber
• end of second piece inserted into groove
• either glued into position to make it permanent or left without glue to allow it to be taken apart or adjusted

Question 8

What is a housing joint used for?

Answer 8

• framework construction
• cabinets
• shelving

Question 9

What is a half lap joint?

Answer 9

• simple joint
• made by cutting a ‘step’ in the end of each piece of timber
• very easy to mark out and cut with a tenon saw
• large gluing surface area so strong

Question 10

What is a half lap joint used for?

Answer 10

• simple frames
• boxes

Question 11

What is a dowel joint?

Answer 11

• made by marking the position of the dowels on both pieces of timber (positioned like a butt joint)
• holes drilled for the dowels
• wood glue is put into the holes and the dowels hammered into position
• two pieces clamped together until the glue is dry

Question 12

What is a dowel joint used for?

Answer 12

flat pack furniture

Question 13

What is a mortise and tenon joint?

Answer 13

• make a square or rectangular hole (mortise) in one of the parts to be joined with a mortise machine, router, or by drilling and cutting with a chisel
• second piece is cut using a tenon saw or band saw to make the tenon
• glue is spread into the mortise
• two pieces joined and clamped together until dry

Question 14

What is a mortise and tenon joint used for?

Answer 14

• frame constructions for tables
• chairs

Question 15

What are knock-down (KD) fittings?

Answer 15

• used to manufacture flat pack furniture
• relatively easy to use with a limited number of simple tools
• wide range of standardised KD fittings that are interchangeable
• can be used on a wide range of products

Question 16

What are modesty blocks?

Answer 16

• small, rigid polymer blocks
• have moulded holes that take screws that are used to join the block to panels
• could be used on cupboards and storage units

Question 17

What are barrel and nut bolts?

Answer 17

• use a cross dowel that is fitted into one of the pieces to be joined
• bolt inserted through the other piece of timber and tightened into the cross dowel
• often used in bed frames

Question 18

What are cam-lock connectors?

Answer 18

• consist of metal dowel that is screwed into one of the pieces
• cam is a disk that fits into a pre-drilled hole
• when disk is rotated with a screwdriver, the collar on the dowel locks into the cam and pulls both pieces tightly together
• used in flat pack furniture

Question 19

What are wood screws?

Answer 19

• used for screwing two pieces of wood together where the thread is needed only at the bottom
• the top part is drilled with a clearance hole that the screw pushes through
• bottom piece of wood has a pilot hole (thinner than the thread) so that the thread bites into the timber

Question 20

What are coach bolts?

Answer 20

• used to join wood pieces together
• under domed head of bolt is a square piece that digs into the wood when tightened, preventing the bolt from rotating
• used for fitting door locks or in street furniture such as wooden benches

Question 21

What are the wood forming processes?

Answer 21

• lamination
• steam bending
• machine processes
  
  • turning
  • milling
  • routering

Question 22

What is lamination?

Answer 22

• bonds material together
• uses wood veneers of thin manufactured board, which can be glued together and bent over a former so that when dry they form a thicker board in the shape of the former
• held while drying by clamps or a vacuum bag
• usually parts need to be trimmed to final size

Question 23

What is steam bending?

Answer 23

• combined heat and steam make strips of wood pliable so they can be shaped over a former
• wood is placed into a steam box where it will absorb the steam
• the wood is then bent over a former and clamped until it dries
• quicker than laminating and less wasteful

Question 24

What is turning?

Answer 24

• machines wood on a lathe
• three turning methods
  
  • turning between centres
  • turning on a faceplate
  • turning in a chuck

Question 25

What is turning between centres?

Answer 25

used to machine a spindle such as chair or table legs

Question 26

What is turning on a faceplate?

Answer 26

used to machine items such as domes or bowls

Question 27

What is turning on a chuck?

Answer 27

• used to grip item as it is machined
• e.g. drilling the end of a spindle or holding the base of a small bowl to allow access to the inside surface

Question 28

What is milling?

Answer 28

• used for small size, basic jobs such as rough prototype or roughing out a small hole or channel
• slow process and milling machines don’t have as large a work area as CNC routers
• can be operated manually or by CNC

Question 29

What is routering?

Answer 29

• used to machine slots and holes in wood, or to make decorative mouldings on the edges, for example on a table top
• can be manual plunge routers or CNC