Most economical method of sawing wood is:
Converting Logs to Lumber
After a tree is felled, the log must be sawn into usable planks or boards. The method of sawing is crucial as it affects the cost, the amount of waste, the strength of the timber, and the appearance of the grain pattern on the final product. The choice of method depends on the intended use of the wood and the desired balance between economy and quality.
📝 Detailed Analysis of the Options
(a) Ordinary Sawing
This is the correct answer. Also known as flat sawing or plain sawing, this is the quickest, easiest, and most economical method. The log is passed through the saw, and parallel cuts are made straight through it without rotating the log. This method produces the maximum yield of usable lumber with minimum waste and labor, making it the cheapest option.
(b) Quarter Sawing
In this method, the log is first cut into four quarters (quadrants). Each quarter is then sawn separately with cuts made perpendicular to the annual rings. This produces a beautiful, straight grain pattern and results in wood that is less prone to warping. However, it is more time-consuming, requires more handling of the log, and produces more waste, making it more expensive than ordinary sawing.
(c) Tangential Sawing
This method involves cutting the boards tangentially to the annual rings, at right angles to the medullary rays. It is similar in some ways to plain sawing but is a more specific technique. While it can produce strong planks, it is not typically considered the most economical method overall compared to simple ordinary sawing.
(d) Radial Sawing
Also known as rift sawing, this method involves making cuts radially from the center of the log outwards, almost parallel to the medullary rays. This produces the most stable wood with the straightest grain, which is highly resistant to warping. However, it is the most complex and wasteful method of all, resulting in the highest cost.
📊 Comparison of Sawing Methods
| Method | Cost & Speed | Waste | Resulting Quality |
|---|---|---|---|
| Ordinary Sawing | Lowest Cost, Fastest | Minimal | Prone to warping, mixed grain |
| Quarter Sawing | High Cost, Slower | Moderate | Stable, straight grain, attractive |
| Tangential Sawing | Moderate Cost | Moderate | Strong planks, specific grain |
| Radial Sawing | Highest Cost, Slowest | Maximum | Most stable, straightest grain |
💡 Study Tips
- Ordinary = Economical: Think "ordinary" means simple, fast, and cheap. It's the most straightforward way to get planks from a log.
- Quality Costs More: Methods like quarter and radial sawing produce higher quality, more stable wood, but this comes at the cost of more time, labor, and waste.
- Visualize the Cuts: Imagine a round log. Ordinary sawing is just slicing it from top to bottom. Quarter and radial sawing involve turning the log and making more precise, angled cuts, which naturally takes more effort.