Otak Udang

INTRODUCTION

The common Malaysian name for the trees and timber of Buchanania spp. (Anacardiaceae). Vernacular names applied include otak udang (Peninsular Malaysia) with various epithets, kepala tundang (Sabah), kepala tundang tungkai pendek (Sabah), lamak ketam (Kedah) and rengas ayam (Peninsular Malaysia). Major species include B. arborescens and B. sessifolia. The sapwood is lighter in colour but is not clearly defined from the heartwood, which is pinkish brown, often with a grey tinge.

Also known as Charoli (India); Pauhan and Pauhan ambon (Indonesia); Pink satinwood (Papua New Guinea); and Balinghasai (Philippines).


DENSITY

The timber is soft to moderately hard and light to moderately heavy with a density of 465-690 kg/m3 air dry.


NATURAL DURABILITY

The timber is non-durable when exposed to the weather.


TEXTURE

Texture is rather fine and even, with straight or slightly interlocked grain.


STRENGTH PROPERTIES

The timber is reported to be rather weak.


MACHINING PROPERTIES

The timber is reputed to work easily and planes to a smooth finish. Sawdust may cause dermatitis.


AIR DRYING

The timber seasons well.


KILN-DRYING

Kiln-drying of 25 mm thick boards from green to 12% moisture content takes about 3 days. Boards containing tension wood may distort badly.


SHRINKAGE

Shrinkage is moderate to high.


USES

The small size of the tree precludes any extensive utilisation of this timber. The timber has been used for light temporary construction, plywood, match boxes and cheap cigar boxes. Other uses include furniture, light framing, turneries and blockboards.


REFERENCE

  1. Wong, T. M. 1982. A Dictionary of Malaysian Timbers. Revised by Lim, S. C. & Chung, R. C. K. Malayan Forest Records No. 30. Forest Research Institute Malaysia, Kuala Lumpur. 201 pp.