Introduction Sentang, known by its scientific name Azadirachta excelsa, is a light hardwood species native to Malaysia. It features a pale straw-colored sapwood with a moderately defined reddish-brown heartwood. Sentang's versatility, moderate density, and ease of workability make it an ideal choice for a wide range of applications.
Key Characteristics
Density: Sentang has a moderate density of 560-770 kg/m³ when air dry, making it a light hardwood. Plantation-grown Sentang tends to have a slightly lower density, especially in younger trees.
Durability: It is classified as non-durable, requiring preservative treatment for outdoor or exposed uses.
Machining: Sentang is easy to work, with excellent finishing qualities. It performs well in boring, planing, and shaping, making it suitable for intricate designs.
Strength: Classified under Strength Group C, Sentang provides moderate strength suitable for furniture and interior applications.
Applications
Sentang wood is widely used in:
High-Class Joinery: Ideal for custom joinery due to its fine finish and workability.
Furniture Manufacturing: Its moderate hardness and smooth finish make it a popular choice for furniture.
Interior Finishing: Suitable for panelling, partitioning, and mouldings in residential and commercial spaces.
Plywood and Flooring: Used in the production of plywood and for interior flooring applications.
Ornamental Items: Perfect for crafting decorative items due to its fine texture and ease of shaping.
Drying and Shrinkage
Air Drying: Sentang seasons quickly, with minimal defects like twisting or end-checking. It takes approximately 2-4 months to air dry depending on thickness.
Shrinkage: With very low shrinkage rates (0.5% radial and tangential), Sentang maintains its shape well after drying, making it ideal for stable construction and joinery.
Conclusion Sentang wood is an excellent material for high-end joinery, furniture, and interior finishing projects. Its workability, moderate strength, and minimal shrinkage ensure both durability and aesthetic appeal.
INTRODUCTION
The Standard Malaysian Name for the timber of Azadirachta excelsa (Meliaceae). Other vernacular names applied include limpaga (Sabah), which is also applicable to some other members of the family, and ranggu (Sabah and Sarawak), which is also applicable to Koordersiodendron pinnatum (Anacardiaceae). Only one species has been recorded in this country. The sapwood is straw-coloured or pale red and is moderately sharply differentiated from the heartwood, which is reddish brown.
Also known as Neem (India); Bawang kunyit, Kayu bawang, Mimba, Nibwak and Surian bawang (Indonesia); Azadirachta (Papua New Guinea); Danggo and Maranggo (Philippines); Sadao-thiam and Thiam (Thailand); and Sau dau (Vietnam).
DENSITY
The timber is moderately hard and moderately heavy with a density of 560-770 kg/m3 air dry. It is classified under Light Hardwood in Malaysia. However, sentang from the plantations may have lower density, e.g. 5-year-old sentang (340-600 kg/m3) and 8-year-old sentang (482-648 kg/m3).
NATURAL DURABILITY
The timber is non-durable.
TEXTURE
Texture is slightly coarse and uneven, due to a tendency towards a ring-porous structure.
STRENGTH PROPERTIES
The timber falls into Strength Group C (Burgess, 1958).
MACHINING PROPERTIES
It is generally easy to work, taking a good finish. The boring properties are rated as good and planing and shaping as moderately good. Tests in Sabah showed that the timber peels well without pretreatment.
AIR DRYING
The timber seasons fairly rapidly, with only slight twisting and end-checking as the main sources of degrade. 13 mm thick boards take approximately 2 months to air dry, while 38 mm thick boards take 4 months.
SHRINKAGE
Shrinkage is very low with both radial and tangential shrinkage averaging 0.5%.
USES
The timber is suitable for high class joinery works, furniture, interior finishing, panelling, mouldings, partitioning, plywood, flooring and ornamental items.