section 5B Flashcards
Two main types of timer finish
rough sawn - Unplanned rough wood for exterior tasks where finish isn’t important
Planed all around (PAR) - mechanically planed on all sides and finish can be easily applied. used for furniture and internal features
what is seasoning?
The process of drying wood as high moisture content can cause uneven evaporation of wood and cause faults like cupping twisting bowing.
two types of seasoning
air drying - planks are stacked and air is allowed to circulate - slower and less effective and efficient kiln drying - more expensive but more effective as it uses more heat and pressure
manufactured board
- two processes n examples
lamination - wood layers is bonded together using an adhesive, plywood examples
compression - wood shredds to fibre and pulp is compressed together at high pressures and
veneer and two tvpes
a thin layer of natural timber placed on cheaper woods
rotational- a tree trunk is turned on an industrial machine and knife cut
Advantages of manufactured boards
cheaper and environmental better - low grade recycled wood is used
no defects(warping twist cupping bowing or nots) available in large sheets which saves energy joint sheets together
large variety of smooth finishes veneers and laminates
disadvantages of manufactured board
- Will blunt tools
- Edges must be covered and treated
- Dust particles may be hazardous adhesive particles can be hazardous
sustainable timber production
unsustainable production causes desertification and deforestation and global warming provenance(the supplier or retailer being able to prove the wood is sustainable) has to be sought after. Organisations like the forest stewardship council help this
manufactured board stock thickness and sizes
thickness start at 3mm and increase in intervals of 3,,
lengths start. available in full sheets of 2440mm by 1220mm
veneer stock thickness
available in thickness ranging from 0.4 to 4.5mm but typically 1.5mm
plank stock width and lengths
lengths start at 1.2m and increase in 0.3m to 4.8m
widths increase in 25mm
dowels and mouldings
some wood can be bought in designs called mouldings. an example is an architrave or skirting boards
dowels are cylindrical rods used for joining pieces of woods
3 holes used for woodscres
pilot hole - for main body of screw with threads to be inserted
shank hole - for shank of screw ( a non threaded part that creates a gap between wood)
countersink hole - some screws are countersunk and need a special hole to lie in line with wood
what are nails and pins and their difference
threadless versions of screws used to permanently fix pieces of wood together. pins are typically thinner than nails and have less pronounced head so are more permanent and harder to remove
types of nails and pins
panel pin - thin diameter and head to hide in material
tack - big head to attach upholstery to carpet
round wire nail - all purpose nail which gets galvanised
what is rebating a hinge and types of hinges
door hinges need to be rebated by cutting groove into door.
butt hinger
piano hinge
flush hinge
drilling factors to consider
type of bit used, so right shape and size is cut
depth of cut
feed rate, as too high right can put too high pressure on part but too Low can cause chip clogging
speed - too high speed can cause scorching
two types of drills
pillar drill - good for accuracy and power
cordless drill - high adaptability and portability
types of drill bit
wood drill bit
twist drill bit
countersink bit
wasting, abrading, sanding tool
wasting tools - a smoothing plane or chisel
abrading - file or surfer(cheese grater like blade)
sanding - glass paper by hand or sanding machines
wood turning technique
a wood lathe is used to spin materials and special chisels calls scraper gouge and parting tool are used
bending
wood can be bent by increasing the moisture content to get cool shaped and held in place. a steamer box is used to increase moisture in wood fast
knockdown fitting
used with flat pack furniture as temporary fixing that joins pieces together with screws that are easily dismantled
flatpack furniture advantages and disadvantages
flatpack furniture is mostly made of manufactured board so :
a : easy to transport
low cost compared to traditional
easy to disammeble
easy tp assemble with experience :
d: need too be constrctured
prone to moisture and chip damage
2 purposes of finish
aesthetics - make grain stand out,
match with other materials
apply a sheen
protection - fungal rot, waterproof , tougher, easy to disinfect
tanalising
sinking wood preservative into rough sawn timber by using pressure in a vacuum for deeper and longer lasting protection
types of wood finishes
wood preservative - protects wood from rot and needs regular reapplication
oil - soaks into wood and protects from moisture and enhances grain but need reapplication
stain - colours wood, no protection
wax - rubbed into wood with cloth and enhances grain
