Seasoning Timber Flashcards
How can you store timber?
Ivan K
Horizontal racking
Vertical racking
What are some common problems that occur without seasoning natural timber?
Ivan k
Warping, cupping, bowing, twisting
What is conversion?
Ivan K
Wood conversion is the process where a newly felled tree is cleaned up and cut into workable lumber
What is seasoning timber?
Ivan K
Seasoning of timber is the process by which moisture content in the timber is reduced to required level. By reducing moisture content, the strength, elasticity and durability properties are developed. A well-seasoned timber has at most 15% moisture content in it.
How is timber season seasoned?
Ivan K
There are two main ways of seasoning timber, Natural (Air) and Artificial (Kiln) drying. Both methods require the timber be stacked and separated to allow the full circulation flow of air, etc. around the stack. The temperature and humidity are gradually changed (usually reduced) to a state similar to the environment for the final use of the timber.
What is of Converting Wood by Slab Sawing?
- Harry de Ferry Foster
The cheapest, first cut made into a tree which is tangential across the whole tree width.
What is Converting Wood by Radial Sawing?
- Harry de Ferry Foster
Most expensive cut of a tree, as the log must first be sawn into quarters first. The resulting wood is less prone to warping or movement.
What is Converting Wood by Blauk sawing?
- Harry de Ferry Foster
Blauks of timber have surrounding sapwood removed, but are large, full cross sections of a tree.
What are the two main types of cut by which wood can be Converted?
- Harry de Ferry Foster
Wood may be cut tangentially or radially when converting wood into timber.
When is the best time to cut down a tree for conversion?
- Harry de Ferry Foster
Winter, or a slow growing season - this is because there is less sap at this time.
Why are stick placed between boards when seasoning timber?
- Humphrey Marsh
To enable air to circulate between them.
When artificial Kiln Seasoning timber, why is steam introduced?
- Humphrey Marsh
It soaks and penetrates the wood, which allows for greater temperature and humidity control.
Why is Rough Sawn timber sold as nominal sized?
- Humphrey Marsh
because the timber is cut with little precision, and so can vary in measurements by some millimetres. Hence the timber is sold as ‘nominally’ 25mm thick, for example, and may arrive at 23mm or 28mm thick.
What are the two types Of storage of timber in workshops storage?
- Humphrey Marsh
Horizontal and Vertical racking
What are the advantages of natural air seasoning?
- Humphrey Marsh
It is cheap and requires little skill compared to kiln seasoning.
What does hygroscopic mean?
- Krystian Shanahan
the ability to give out or take in moisture.
Timber and some polymers are hydroscopic
What are the two forms of processed timber that are available after conversion?
- Krystian Shanahan
Rough sawn or planed
What are the two options when buying planed timber?
- Krystian Shanahan?
Planed all round (PAR) and planed both sides (PBS)
What happens to damp wood in dry air?
-Oscar Lawson
It shrinks
What happens to dry wood in damp air?
-Oscar Lawson
It swells
What does reducing the wood’s moisture to less than 20% do?
-Oscar Lawson
It increases the strength and stability of the wood, making it more immune to rot and decay.
What is plywood?
-Oscar Lawson
An odd number of layers of wood (typically 3 or 5) stacked so that the grain is going in the perpendicular directions on each layer
What is chipboard?
-Oscar Lawson
Compressed fibres of wood that are tightly packed and glued together, or Impregnated with adhesive resin.
If the wood is dried incorrectly what can occur?
Warping, such as cupping, bowing, or twisting.
How much water content can unseasoned wood have ?
up to 50%!
What effect does seasoning the wood have?
It makes it easier to machine, more stable, and less likely to warp
Where in a tree is heartwood found?
-Lucas M
The centre
When are trees usually felled?
-Lucas M
When they reach maturity and in the winter (or off season) when there is less sap due to slower growing.
What is the slab method of sawing (converting) timber also known as?
-Lucas M
The Plain or through and through method.
What is the cheapest and quickest way of converting timber?
-Lucas M
Slab / plain / through and through method.
After converting timber what are the two forms wood is available in?
-Lucas M
Rough sawn or planed
For timber, what does PBS stand for?
-Ssnehnil G
Planed both sides
For timber, what does PAR stand for?
-Ssnehnil G
Planed all round
What are the four standard sizes of available timber?
-Ssnehnil G
Plank, Boards, Strips, Squares
What are the top five most common manufactured boards?
-Ssnehnil G
MDF, Plywood, Blockboard, Chipboard, Hardboard
Manufactured board sheets typically come in what dimensions?
-Ssnehnil G
2.4m x 1.2m
What are the two ways of storing timber in a storage room / workshop when they’re ready for manufacturing?
Torsai K
Vertical stacking and horizontal stacking
What are the two main ways of seasoning?
Torsai K
Air seasoning and artificial kiln seasoning.
What type of wood seasoning uses steam?
Torsai K
Artificial kiln seasoning.
in a lumber mill, what are the largest bandsaws used for?
-Alfie Turner
for the first slab sawn cut of each tree.
What conversion method is the cheapest?
-Alfie Turner
The Slab sawn method
When does damp wood shrink?
-Alfie Turner
in dry air
When does dry wood swell?
-Alfie Turner
in damp air
Why are trees felled during winter?
Nathan P
There is less sap due to the slower growth.
What is Conversion?
Nathan P
The process of sawing a log into marketable timber
What is the cheapest, quickest method of converting timber?
Nathan P
Slab/Plain/Through and through
What time of year is there less sap in trees?
-Oscar Mabon
Winter
What saws are used to cut the wood in the conversion process at a lumber/timber mill or sawmill?
-Oscar Mabon
Large bandsaws or circular saws.
What type of warping is radial sawn timber less prone to?
-Oscar Mabon
radial sawn timber is less likely to cup or twist
What happens to Unseasoned ‘Green Timber’ if used in manufacturing?
Caspar Tyser
It twists badly and joints open.
Reducing the moisture to less than ……. increases the strength and stability of wood, making it more immune to rot and decay.
Caspar Tyser
Reducing the moisture to less than …20%…. increases the strength and stability of wood, making it more immune to rot and decay.
What are placed between the boards in Natural Air seasoning to enable air to circulate between them?
Caspar Tyser
Sticks
