The timber is a Heavy Hardwood with a density of 800-880 kg/m3 air dry. The timber is moderately durable under exposed conditions.
Tên gọi khác: Chò Chai
The Standard Malaysian Name for the heavy, red to red-brown timbers of the genus Shorea(Dipterocarpaceae). Vernacular names applied are too many to be listed here except for the more common ones, viz. balau laut merah (Peninsular Malaysia), balau merah(Peninsular Malaysia), damar laut merah (Peninsular Malaysia), membatu (Peninsular Malaysia), red selangan batu (Sabah and Sarawak), selangan batu merah (Sabah and Sarawak), semayur (Sarawak), seraya (Peninsular Malaysia) and seraya batu(Peninsular Malaysia). Major species include S. collina, S. guiso, S. inaequilateris, S. kunstleri and S. ochrophloia. The sapwood is pink, purple-brown or grey-brown and is fairly distinct from the heartwood, which is light to deep red-brown.
Also known as Balau merah and Gisok(Indonesia); Chò Chai (Vietnam); Chan, Lantan and Teng-tani(Thailand); Guijo (Philippines); Mai si khao (Laos); Selangan merah (Brunei).
AIR DRYING
The seasonig properties of some of the species tested are summarised below:
|
Species |
Time to air dry (months) |
Remarks |
|
|
13 mm |
38 mm |
||
| S. guiso |
4 |
6 |
Fairly slow drying; moderate end-checking; slight cupping, splitting, surface-checking, insect attacks and staining. |
| S. kunstleri |
4 |
6 |
Fairly slow drying; moderate end-checking; slight splitting and surface-checking. |
| S. ochrophloia |
3 |
5 |
Fairly slow drying; moderate end-checking; slight splitting and surface-checking. |
KILN-DRYING
Kiln Schedule G is recommended.
Kiln Schedule G
|
Moisture Content (%) |
Temperature (Dry Bulb) |
Temperature (Wet Bulb) |
Relative Humidity (%) (approx.) |
||
|
° F |
° C |
° F |
° C |
||
|
Green |
120 |
48.5 |
115 |
45.0 |
85 |
|
60 |
120 |
48.5 |
113 |
45.0 |
80 |
|
40 |
130 |
54.5 |
123 |
50.5 |
80 |
|
30 |
140 |
60.0 |
131 |
55.0 |
75 |
|
25 |
160 |
71.0 |
146 |
63.5 |
70 |
|
20 |
170 |
76.5 |
147 |
64.0 |
55 |
|
10 |
180 |
82.0 |
144 |
62.5 |
40 |
SHRINKAGE
The shrinkage of red balau is summarised below:
|
Species |
Shrinkage (%) |
Remarks |
|
|
Radial |
Tangential |
||
| S. guiso |
1.6 |
3.6 |
High shrinkage |
| S. kunstleri |
2.2 |
3.3 |
High shrinkage |
| S. ochrophloia |
1.4 |
3.2 |
High shrinkage |
