Sim, H.C. & Mohd Arshad Saru
Furniture Testing - FRIM Experience
Lim, N.P.T. , Korai, H. & Imamura, H.
Properties Of Particleboard Made From Acacia mangium
Abdul Rashid Abd. Malik
Fire Retardant Treatments For Timber
Wong, A.A.H., Hong, L.T. & Ling, W.C.
Controlling Sapstain In Sapwood Timbers With Common
And Novel Anti-Sapstain Preservative : Relevance To Sarawak
Jenang, K. & Inoue, M.
Effect Of Incising Technique On Preservative Penetration Of
Refractory Timber Species
Choong, E.T., Roliadi, H. & Chin,Y.H.
Wood Properties Of The Dipterocarpaceae
Sugawa, T. & Salang, A.T.
Microscopic Structures Of Dipterocarp Timber Found In Sarawak
Imamura, H. & Jenang, K.
An Overview Of Transparent Coating For Exterior Use
Ismail Bin Sulaiman
New Developments In Kiln Schedules For Some Sarawak Timbers
Ling, W.C.
The Durability Of Sarawak Timbers In Soil Contact
From these studies, it is concluded that Penyau (Upuna borneensis)
is the second most durable timber after Belian and not Selangan batu
(Shorea spp.)
as previously thought. CCA was found to be the most effective wood
preservative for tropical use. From analysis of the performance of treated
timber, it is concluded that the required retention for CCA treated timber
use in tropical ground contact should be revised from the current value of
16 kg/m3 to at least 20 kg/m3 and that Creosote and
other preservatives cannot give long term protection.
Duju, A. & Kuroda, N.
The Relationship Between Basic Density And Mechanical
Strength Properties Of Some Sarawak Timbers
The linear relationship between basic density and the strength properties
were found by linear regression. Coefficients of determination ranging from
0.85 to 0.94 were obtained for both green and air dried conditions. There
is a strong correlation between MOE and MOR for both green and air-dried
conditions.
The results of the study indicated that basic density can be used as a
strength indicator for mechanical stress grading of Sarawak timbers.
Inoue, A. & Siti Hanim Sahar
Formaldehyde Issue In Wood-Based Panels
Wong, T.C., Fujiwara, K. & Chan, C.S.
A Diagnostic Approach To Bandsaw Maintenance
Hashim Haji Bojet & Jimbat, T.
Current And Future Development Of Timber Industry
(Primary Processing) In Sarawak
Peter, C.S K., Siew, K.Y. & Foo, E.P.L.
A Wood-Waste Combustion Kiln For Small And Medium Sawmills
In Sarawak
Imamura, H., Lim, N.P.T. & Wong, T.C.
Some Prospects Of Woodwaste Utilisation In Sarawak -
A Perspective
Wong, A.H.H., Singh, A.P., & Ling, W.C.
Major Decay Types Recognised In An Extremely Durable
Timber Species Belian (Eusideroxylon zwageri) From East Malaysia
Siti Hanim Sahari & Inoue, A.
Bonding Properties Of Bonded-Wood Products Made In Sarawak
Daud Sulaiman
Management Of Safety And Health In The Timber Industry
Analyzing any accident, and you may find that the root of the problem is
poor safety and health management. This paper will try to highlight the
duties of employers according to OSHA '94:
Kuroda, N. & Ling, W.C.
Measurements Of Moisture In Wood
Foo, E.P.L. & Tan, J.L.
A Guide Of The Use Of Use Of Electrical Resistance-Type
Timber Moisture Meter
Furniture testing to evaluate the capability of a piece of furniture
to perform its intended functions is an important step in the designing
and manufacturing of furniture. More than 200 units of locally made
furniture have been tested by the FRIM Furniture Testing Laboratory (FTL)
since its establishment in 1989. Majority of these furniture required
modifications to satisfy the requirements of commonly referred-to
standards. Poor selection of material, poor gluing and weak joints, design
errors such as wrong dimensioning and specifications are among the common
faults detected.
Single-layer particleboards of targeted densities 600, 700 and 800 kgm-3
made from 0.6 mm thickness flakes of 10-year old Acacia mangium with
10% urea formaldehyde (UF) and melamine urea formaldehyde (MUF) resins were
found to satisfy the stipulated minimum requirements of Type 18 Japanese
Industrial Standard JIS A 5908-1994. Bending strength under air-dry and
wet conditions, and bonding efficiency were also found to increase with
board density irrespective of resin type used. As for the three-layer
particleboards aimed at 700 kgm-3 density using the same resins
(12% surface and 7% core), board properties also met the requirements
of Type 18 board. Boards made with MUF resins (Type M and P ) exhibited
better bending strength (air-dry) and bonding efficiency properties when
compared to that made with UF. Similarly, thickness swelling of Type M
and P boards were better than that of Type U boards. The conclusion drawn
from this preliminary evaluation is that 10-year old Acacia mangium
is a suitable raw material for particleboard manufacture.
At present, several types of fire retardant chemicals are available for
timber and timber products. The chemicals can be applied on timber either
by impregnation process or surface coating. Some fire retardant treatment
reduces the spread of flame rating of timber to Class 0. Some fire retardant
coatings also improve the fire resistance ratings of timber and timber-
based products. Timber treated with fire retardants can meet the
requirements as specified in the Building Regulation and therefore
provide alternative to non-combustible materials. Test methods for
evaluating the fire properties of timber and timber building components
are also described.
A major challenge befalling the Malaysian timber preservation industry
concerns the selection of suitable anti-sapstain wood preservatives to
adequately protect sapwoods and decay-susceptible heartwoods of commercial
timber species using the dipping or vacuum-pressure treatment against
blue-stain and mould attack. Sapstain permanently discolours the wood thus
posing a particularly undesirable biodeterioration problem in such humid
environments. The search for safer, yet effective, anti-sapstain chemicals
prevails, despite the widespread use of sodium pentachlorophenate (NaPCP)
normally applied as mixtures with Borax. PCP is a cost-effective fungicide
but can pose a serious threat to health and the environment. Many
alternative anti-sapstain chemicals are making in-roads in Malaysia and
their efficacy are actively evaluated in comparison with that of NaPCP/Borax.
The relative efficacies of some of these formulations are briefly discussed, and
there is a role for rigorous efficacy tests to aid commercialisation of these novel
preservatives in Malaysia. Ultimately, using safer anti-sapstain chemicals for temporary
protection, many of the currently lesser-utilised, low durability timber species of
Sarawak would eventually find greater value in the international trade, equivalent to
the status achieved for rubberwood in Peninsular Malaysia.
The large number of refractory timber species occurring in Sarawak requires
that the species should be conditioned prior to treatment to improve their
treatability. Incising is considered as one of the most effective and
cheapest methods of improving treatability of the wood. Although incising
produces a rough surface, increases the cost of treatment slightly and
results in some loss of strength, these disadvantages are more
than compensated by increased protection and hence durability, as a result
of improvement in preservative penetration. In addition, incising reduces
the amount of checking and splits that can develop during seasoning.
Wood properties of commercially important Dipterocarpaceae, which include
anatomical features, dimensional stability, dryability, mechanical and
chemical properties, durability and treatability, and gluability, are
discussed. Different species cause variations in anatomical features,
chemical properties, and specific gravity. High specific gravity may
result in low dimensional stability, poor dryability and poor gluability,
but tends to positively affect mechanical properties and durability.
Favorable durability can also be due to high extractive content in certain
species. Extractives to high dimensional stability and decreased wood
permeability, causing treating difficulty. A knowledge of wood properties
is essential to maximize the utilization potential of the Dipterocarpaceae.
The tropical rainforest of Sarawak is largely dominated by trees from the
family of Dipterocarpaceae, which are commercially important to the timber
industry, and a major revenue earner for the State of Sarawak. Information
on the microscopic structures that are both important to their properties
and identification have been established in order to have a better
understanding of the Dipterocarp trees for effective utilisation.
The durability of transparent coating material for exterior use has always
posed a serious problem both for the manufacturers of coated wood products
and end-users alike. Coating durability is influenced by a combination of
factors, namely, the type of coating material, coating techniques and the
fundamental behaviour of the substrate on exposure to the exterior. The
durability of a coat of paint for outdoor use can be enhanced by adopting
suitable coating technique, applying ultraviolet light resistant coating
material and stabilizing the wood dimension. In addition, relevant research
findings and current research work in coating technology in Japan are also
highlighted.
Kiln drying schedules for eleven species of timbers from Sarawak were
determined using the method developed by the Forestry and Forest Products
Research Institute (FFPRI) of Japan. Degrades obtained from each "Quick
Drying Test" are graded and these are used to derive an initial kiln drying
schedule from the charts developed by Hisada et al. This rough schedule is
later improved using the "Optimum Schedule Test". These new schedules were
found to be more refined than those currently recommended. The initial
drying schedules for an unknown species can be determined within a week.
In 1976, a field trial based on ASTM D1758 was established in Bako National
Park. The following year, a second site was established at Oya Road, Sibu.
Both preservative treated and untreated timber of dimensions 19 x 19 x 457mm
were put to test and all specimens were inspected at 6 months intervals and
graded for fungal and termite attack. Since establishment, a total of 50,000
specimens have been installed. The present study is confined to performance
of timber species installed between October 1977 and October 1989 at the Oya
Road site. Data on the performance of timber treated with CCA and creosote
were compared with untreated timbers.
Basic information on mechanical properties for promoting effective
utilization of Sarawak timber species as construction materials were
tabulated. The relationship between basic density and compressive strength,
MOR and MOE of small clear specimens were investigated.
Formaldehyde-based resins has been widely used for many years throughout
the world in the manufacture of wood-based panels. Since formaldehyde is a
highly reactive substance and has harmful effects on human being,
formaldehyde has become a hot issue in advanced countries. There are slight
variations of regulations and guidelines on formaldehyde emissions among
advanced countries. A few methods are currently being used in measuring
formaldehyde emission such as dessicator method and perforator method.
Some methods of reducing formaldehyde emission include the use of low
formaldehyde emission (LFE) urea formaldehyde adhesives or formaldehyde
free adhesives eg. Phenol, addition of formaldehyde scavengers in urea
formaldehyde ahhesive, modification of bonding conditions and post-
treatments on the wood-based panels.
The need to improve preventive maintenance of sawmill machinery in Sarawak
is explained. A diagnostic approach to bandsaw machine maintenance is
introduced together with fault-detection methods and tolerance
recommendations.
The design of a 25-tonne brick wood-waste combustion kiln for drying common
furniture-grade timbers like Dark Red Meranti, White Meranti, Nyatoh and
Alan batu is described. It has advantages over other types of kilns in that
it is relatively cheap to build and simple to operate and maintain as it
requires no boiler. 2-inch thick green sawn timbers can be dried to 10 - 12%
in 20 to 35 days depending on species and initial moisture content.
The bulk of woodwaste produced from Sarawak's timber industries
are not effectively utilised as compared to the situation in Japan where a
broad range of utilisation is continually enhanced by research and
development efforts. However, prospects are good, particularly in the
designed Timber Processing Zones, economic exploitation of woodwastes
can be effectively realized in Sarawak.
Belian (Eusideroxylon zwageri) is highly regarded among the naturally
durable Malaysian hardwoods, and is therefore favoured for use in
ground-contact as untreated poles, posts and railway sleepers.
Sampling of Belian heartwood poles in Sarawak revealed only surface
biodeterioration after 20 years in service, with evidence from microscopic
studies to suggest an unusual form of fungal decay, possibly white rot,
giving a false impression of "soft rot" decay (termed here as "pseudo-soft
rot") as seen in the transversed section by transmission electron microscopy.
Previously published works by Swedish and New Zealand studies on decay of
belian heartwood samples from Sabah have confirmed the presence of
widespread bacterial decay caused by tunnelling bacteria. Other commonly
associated bacterial decay types, i.e. bacterial erosion and cavitation,
observed in other timbers, are not found in the decayed tissues of belian
samples. Electron micrographs are provided to illustrate the micromorphology
of bacterial fungal decay patterns in Belian. The wood is found to be very
resistant in fungal decay tests, is rated moderately resistant against the
Australian termite Mastotermes darwiniensis, but is very resistant
under Sarawak conditions. However standing trees are found to colonised by
termites and brown rot. These studies serve to illustrate that even the
remarkable durable belian (and other durable Malaysian timbers) is
not entirely immune to biological deterioration, dispelling the widely
held belief that belian heartwood is indestructable, although the wood
which is impermeable to preservatives, can be used in a severe decay
hazard environment (soil-burial).
Several types of bonded-wood products were collected from various wood
industries throughout Sarawak and their bonding properties tested in
accordance to the Japanese Agricultural Standard (JAS). A general view
on the bonding properties of our products is discussed and factors
affecting the bonding properties are outlined. Suggestions are also
given to overcome the problems that are regularly encountered in
gluing wood.
The Occupational Safety and Health Act, 1994 (OSHA '94) is a legislative
framework to promote, stimulate and encourage high standards of safety and
health at work. It covers every industry, including forestry. This Act
shifts the responsibility for safety and health from the government to the
employers and employees themselves, based on our version of Lord Roben's
philosophy which says :
THE RESPONSIBILITY TO DO SOMETHING ABOUT SAFETY AND HEALTH AT THE PLACE OF
WORK LIES WITH THOSE WHO CREATE THE RISKS AND THOSE WHO WORK WITH THE RISKS.
This short paper describes the wood-moisture relationship and reviews
the current measuring method of wood moisture content. Fundamental aspects
of moisture measurement, types of moisture meters, the need for non-
destructive measurement of moisture content, its effect on product quality
and production process and the reasons for setting up a database of physical
properties of Sarawak timbers for measuring moisture content of wood
non-destructively are discussed.
This paper describes the operating procedures of timber moisture meters
with respect to accuracy, temperature compensation and continuous mode of
operation for kiln. The factors affecting moisture meter readings are also
explained. The calibration of both Techtron DCR 7-T and GANN hydromette
HT-75 electrical resistance-type timber meters were determined for seventy
seven groups of timber and the calibration results are tabulated in the form
of a species moisture content correction chart.