TIMBER INFORMATION SHEET

.

Octomeles sumatrana

IMPORTED TIMBER

C

AVAILABILITY

General Description

TIMBER PROPERTIES

Erima is native to Indonesia, Malaysia, the Philippines, Papua New Guineaand the Solomon islands.

Sawn timber imports reached a maximum volume in 1980, but have sincedeclined. For the Year ended 31 March 1984 they amounted to 791 cubicmetres

Drying

The sapwood is usually Yellow and not clearly distinguish able fromthe heartwood which is commonly brown to grey, occasionally showinga faint purple or pink tinge. The grain is moderately coarse to coarse intexture. Interlocked grain is common, giving rise to a distinct ribbonfigure. When dry the timber has little odour, but when wetted it givesoff an unpleasant smell. Growth rings are indistinct and the timber isnon-sillceous.

Care is required during drying to prevent degradation such as twist,checking and end-splitting. Stacks should be weighted and filletsclosely spaced. Erima is slow drying and requires a mild kiln schedulePartial air-drying under cover prior to kiln-drying will reduce degradation

The heartwood is considered perishable/non-durable. Most of the importedmaterial arrives in the untreated green sawn condition, but erima can betreated by pressure methods and the diffusion process. The u ntreated woodis susceptible to powder-post beetle (Lyetus species) and ambrosia beetleattack

Durability and Preservation

I^I' TEA(* 4;a O, ~

, v

4;:' *\67' st'?-

Physical and MechanicalProperties

Source

Papua NewGuinea

Density at12% MoistureContent

Ikg/in 31

WesternSamoa

SabahIMalaysia)

Some Physical and Mechanical Properties of Erima

HardnessModulusModulus(kN)ofof

ElasticityRupture(GPa)(MPa)

366

232

G

352

38.0

D

Notes

o G = green timber. D = timber at 12% moisture content. R = in radial direction. T = in tangential direction

o Strength values refer to 20mm square clearwood specimens

o References Density and strength values are from Orman. H. R. . Haslett. AN. . and Carter. L. C. "Properties ofWestern Samoan Timbers XIV. orto", e!ess"""tram MIQ. Timber Engineering Report N0 8". Forest Research Institute. N Z Forest Service. Rotorua 1977. Shrinkage values for Sabah f rom Bu rgess. P. F. "Timbersof Sabah", Forest Department. Sabah 1966. Shrin kege values for Papua New Guinea from "Properties andUses of Papua New G uinea Timbers". Forest Products Centre. Papua New Guinea March 1970.

Working and FinishingProperties

56.0

19.0

37.0

G

28.0

6.1

D

52.0

7.7

3.0

G

5.3

3.7

USES

PercentageShrinkage fromGreen to 12%Moisture Content

1.5

D

6.3

Erima is easily sawn except in cross-cutting where considerable breakingout of fibres may occur. Machining often results in a woolly finish, butreduction of the cutting angle can alleviate this problem. The timber doesnot have a good reputation for its nailho!ding and screw-holding ability,but it glues well. It polishes well to a silky or satin appearance and alsotakes paint satisfactorily

1.6

O. 5

R

1.4

08

1.9

I. 7

T

Erima has been used extensively overseas in plywood manufacture inhidden use applications, such as backs and core stock. Also, it makes anattractive sliced veneer and peels smoothly in rotary veneer productionOther uses include mouldings, sarking, panelling, internal joinery, shelving,caskets, packing cases and shutter ing

Erima has been used for weather boards in New Zealand for some YearsHowever, experience of its long-term performance - with or without acoating - in this application is limited, and it is not possible to guaranteesatisfactory performance u rider all conditions. Use of boron-salt-treated,air-dried erima weather boards has been unsatisfactory because of bucklingand nail pull-out. Current indications suggest that quarter-sawn, kiln-driederima which has been treated with copper-ch rome-arsenate preservative Issuitable for use as weather boarding. Better performance of the weather-boards is likely with light-toned surface finishes and horizontal (ratherthan vertical or diagonal) use. Flat- or countersunk-head nails should beused and should be at least 60mm in length as specified in NZS 3604(1984) "Code of practice for light timber frame buildings not requiringspecific design"

43

Compiled byNEW ZEALAND FOREST SERVICEPrivate Bag, Wellingtonto whom any enquiries should be addressed

5186

Printed byBUILDING RESEARCH ASSOCIATIONOF NEW ZEALANDMoonshine Road, Judgeford

An introductory sheet to theTimber Information Series

is available on request.

ISSN 01/25680