Keledang


INTRODUCTION

The Standard Malaysian Name for the heavy timbers of Artocarpus spp. (Moraceae). Vernacular names applied include bangkong (Peninsular Malaysia), keledang (Peninsular Malaysia) with various epithets, terap hutan (Sabah) and various other localised names too numerous to list here. Major species include A. anisophyllus, A. dadah, A. heterophyllus, A. integer, A. kemando, A. lanceifolius and A. rigidus. The sapwood is light yellow to yellow-brown, sharply defined from the heartwood, which is brown or orange-brown and turns to dark brown on exposure.

Also known as Keledang (Brunei); Aini, Chaplash, Kathal (India); Keledang, Kelembi, Selangking, Tambang and Tempunik (Indonesia); Hat mi, Mai nang and Mi nang(Laos); Myauklok (Myanmar); Ham, Hang and Kapiak (Papua New Guinea); Anubing (Philippines); Del, Jak and Kanangonna (Sri Lanka); Hat, Kha Num Pan, Khanun and Ma Hat (Thailand); and Mit-nai (Vietnam).


DENSITY

The timber is a Medium Hardwood with a density of 500-945 kg/m3 air dry.


NATURAL DURABILITY

The timber is moderately durable (A. integer and A. lanceifolius) to non-durable (A.dadah, A. heterophyllus and A. rigidus). Specimens of A. lanceifolius treated with 100% creosote were buried at the graveyard test site at the Forest Research Institute Malaysia (FRIM) and after 35 years, 70% of the specimens were destroyed.    


PRESERVATIVE TREATMENT

The treatability of A. lanceifolius is classified as easy.   


TEXTURE

Texture is moderately coarse to coarse and even with interlocked to deeply interlocked grain.


STRENGTH PROPERTIES

The timber falls into Strength Group B (Engku, 1988b), or SG 5 (MS 544:Part 2:2001).


Strength Properties of Keledang

Species

Test Condition

Modulus of Elasticity(MPa)

Modulus of Rupture(MPa)

Compression parallel to grain (MPa)

Compression perpendicular to grain (MPa)

Shear strength(MPa)

A. lanceifolius

Green

14,200

86

45.2

-

14.5

Air dry

15,500

107

58.8

-

12.5

A. rigidus

Green

11,600

78

38.6

4.07

9.2

Air dry

12,200

93

47.5

4.90

9.9


MACHINING PROPERTIES

It is difficult to resaw and cross-cut. Planing is easy to moderately easy and the planed surface is smooth to rough in some tangential boards due to picking-up of grain.


Machining Properties of Keledang 

Species

Test Condition

Sawing

Planing

Boring

Turning

Re-sawing

Cross Cutting

Ease of planing

Quality of finish

Ease of boring

Quality of finish

Ease of turning

Quality of finish

A. lanceifolius

Green

difficult

difficult

easy

heartwood: smooth; sapwood: picking up of grain

easy

smooth

-

-

Air dry

difficult

difficult

easy

smooth

moderately easy

smooth

easy

slightly rough

A. ridigus

Green

difficult

slightly difficult

moderately easy

tangential: smooth; radial: rough due to grain pick-up

difficult

rough

-

-

Air dry

difficult

difficult

moderately easy

smooth

difficult

rough

-

-


NAILING PROPERTY

Nailing property is good.


AIR DRYING

The timber dries moderately slowly. 13 mm thick boards take 3 months to air dry, while 38 mm thick boards take 4 months. The timber dries with minor defects like slight surface- and end-checking. Some insect attacks were noted in A. rigidus during drying.


KILN-DRYING

Kiln Schedule F is recommended.


Kiln Schedule F

 Moisture Content (%)

Temperature (Dry Bulb)

Temperature (Wet Bulb)

Relative Humidity (%) (approx.)

F

C

F

C

Green

120

48.5

111

44

75

60

120

48.5

109

43

70

40

125

51.5

109

43

60

30

130

54.5

109

43

50

25

140

60.0

115

46

45

20

155

68.0

124

51

40

15

170

76.5

136

58

40


SHRINKAGE

Shrinkage is low, the average radial shrinkage from green to air dry is 0.9% and the tangential shrinkage is 2.2%.


DEFECTS

The logs of keledang are generally free from defects, with the exception of some that have heart shakes and small areas of spongy heart. A few pin hole galleries in the sapwood of the logs of A. lanceifolius have been recorded.


USES

The timber is highly prized as a high-class coffin timber and much of the supply is diverted to this use. The timber is also suitable for medium construction, beams, posts, joists, rafters, door and window frames and sills (internal use only), columns (light duty), staircase (balustrades, carriages, risers, tread, bullnose, round ends, winders and stringers), decorative works, flooring, decking, plywood, furniture, panelling, mouldings, joinery, cabinet making, packing boxes and crates as well as ship and boat building (keels, keelsons, framework, masts and spars).


REFERENCES

  1. Engku Abdul Rahman Chik. 1988b. Basic and Grade Stresses for Strength Groups of Malaysian Timbers. Malayan Forest Service Trade Leaflet No. 38. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 13 pp.
  2. Lopez, D. T. 1984. Malaysian Timbers - Keledang. Malaysian Forest Service Trade Leaflet No. 91. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 9 pp.  
  3. Menon, P. K. B. 1986. Uses of Some Malaysian Timbers. Revised by Lim, S. C. Timber Trade Leaflet No. 31. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 48 pp.
  4. MS 544:Part 2:2001. Code of Practice for the Structural Use of Timber: Permissible Stress Design of Solid Timber.
  5. 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.