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DGITIMBER PROPERTIES

DECORATIVE GLULAM PROPERTIES
TIMBERBOTANICAL NAMEDENSITY kg/m3LAMINATE mmTHICKNESS mmBUTT JOINTSRADIAL SHRINKAGE %TANGENTIAL SHRINKAGE %JANKA kNWORKABILITYDURABILITY (Class)STRENGTH GROUP
American OakQuercus Alba7203035Yes3.0%5.0%6Easy to work. Iron when in contact with damp wood may cause black tannin stain.Moderate (3)SD6
Amercian Black WalnutJuglans nigra6109032No4.5%7.8%4.5Easy to work, planer tear out may be a problem. Glues well.Moderate (3)SD2
American Cherry (Myrtle)Nothafagus Cunninghamii7101935Yes3.5%6.6%5.9Easy to glue, finish and work. There is a tendency to tear out, use sharp tool edges.Moderate (3)SD3-SD4
Baltic PinePinus Sylvestris5004235No2.0%4.5%2.1Easy to glue, finish and work except for the knots.Moderate (3)SD6
Sydney Blue GumEucalyptus Saligna8501935Yes5.0%9.0%9.0Relatively easy to work. Glues well.Moderate (3)SD3
BlackbuttEucalyptus Pilularis90019--3.0%6.5%9.1-Durable (2)SD2
BrushboxLophostemon Confertus9001934Yes & No5.0%10.0%9.5Dulls tool edges due to silica. Works and finishes well.Moderate (3)SD3
Canadian Rock MapleAcer Saccharum7401935Yes3.0%6.0%6.4Easy to work. Take care in nailing.Low (4)SD4
Celery Top PinePhyllocladus Aspelenifolius 6501935Yes2.0%4.0%4.5May not be easy to work with due to wood compression.Durable (2)SD5
Cypress PineCallitris Glaucophylla6801934Yes2.5%3.0%6.6Brittle but will accept nail without splitting. Sanding dust may be irritable to some.Durable (2)SD6
DamanuCallophyllum spp.6003335Yes2.5%4.0%4.6Generally easy to work. Glues well.Low (4)SD6
Damanu Slimline8730Yes
European BeechFagus Sylvatice7002130yes4.0%6.0%6.0Easy to work, glue and finish. Pre-drilling may be required for nailing.Low (4)SD4
European BirchBetula Pubescens6702235Yes3.0%6.0%4.5Easy to work, glue and finishLow (4)SD4
European ElmUlmus Pumula6002535Yes---Works, glues and finishes well. Moderate (3)-
European OakQuercus Petraea6902535Yes3.0%6.0%5.5Easy to work. Iron when in contact with damp wood may cause black tannin stain.Durable (2)SD5
European WalnutJuglans Regia6402235Yes2.0%4.0%5.9Easy to work. Iron when in contact with damp wood may cause black tannin stain.Moderate (3)SD4
Fijian MahoganySwietenia Macrophylla5708740No1.5%2.5%3.6Sharp tools are needed to avoid ‘wooliness’. Glues and nails well. Moderate (3)SD6
Hoop PineAraucaria Cunninghamii5302035No2.5%3.5%3.4Works and glues well.Low (4)SD5
Hoop Pine Panel42-5019No
JarrahEucalytus Marginata8203938Yes5.0%7.5%8.5Works, glues and finishes well. Care when nailing.Durable (2)SD4
Jarrah Slimline4530Yes
Jarrah Panel68-9019No
MerbauInstia Bijuga8304530Yes1.5%2.5%8.6May have gum build up on cutting tools. Saw dust may be irritable to some.Durable (2)SD3
N.G. RosewoodPterocarpus Indicus6153035Yes1.0%2.0%4.7Easy to work, glue and finish.Durable (2)SD5
N.G. Rosewood Slimline8730Yes
NyatohPalaquium spp.6504530Yes5.0%6.5%5.0Dulls tool edges due to silica but usually works and finishes well.Low (4)SD7
Pacific TeakVitex Cofassus 8006333No3.5%6.0%5.0Easy to work. Glues well.Durable (2)SD4
Radiata PinePinus Radiata5003335No3.0%4.5%3.3Easy to works except for the knots.Low (4)SD6
Recycled Red HardwoodMixed species700-9508040Non/an/an/a-n/an/a
Recycled Brown HardwoodMixed species700-9508040Non/an/an/a-n/an/a
Recycled OregonDouglas Fir5608040No2.5%4.0%3.1Care is needed when dressing and nailing.Low (4)SD5
River Red GumEucalyptus Rostrata9006030Yes4.0%8.0%10.0Care is needed when dressing due to its interlocked grain.Durable (2)SD5
RosegumE. Grandis7509032No4.5%7.5%8Works, glues and finishes wellModerate (3)SD4
Spotted GumC. Maculata7909032No4.3%6.1%11Not difficult to work with. Somewhat corrosive to aluminiumDurable (2)SD2
Tasmanian BlackwoodAcacia Malanoxylon6401935Yes1.5%4.0%5.9Easy to work, glue and finish. Sanding dust may be irritable to some.Moderate (3)SD4
Tasmanian Blackwood Slimline6330Yes
Tasmanian OakE.regnans, obliqua, deligatensis700-7503035Yes & No2.1-6.6%8.5-13.0%5.0Easy to work, glue and finish.Low (4)SD3
Tasmanian Oak Slimline 8730No
Tasmanian Oak Panel9019No
Tulip OakArgyrodendron Actinophyllum8504030No4.5%8.5%7.3-Low (4)SD3

Timber availability and manufacturing specifications may vary from time to time.

JANKA HARDNESS

There are two measures of hardness referred to in regards to finished timber products. These are abrasion & indentation resistance.

Abrasion is a direct function of the finish coat/s, their hardness as well as their ability to flex.

The usual measure of the ability of the substrate to withstand indentation is the Janka Hardness Test. This measures the force required to embed an 11.28 mm (0.444 in.) steel ball to half its diameter into the wood, thus forming an indentation with projected area of 1 sq. cm.

The Force is expressed in Kilo-Newtons (kN). 1kN = ~100Kg, thus a figure of 5kN means that it requires 500Kg to make 1sq.cm2 indentation that is nearly half a family car! This is more a critical factor when deciding on a species for timber flooring, (where a stiletto on dance floor can make deep indentations on softer timbers) than for, say, kitchen tops.

Kiln Dried timbers have Janka hardness ranging from c.1.5kN for some species of Spruces and Firs to 15.0kN for some exotic species like Wandoo in Western Australia.

FINGER JOINTS

Where it is difficult to obtain enough long laminates, finger jointing of laminates is necessary. Our finger joints are turned so that a butt-joint is shown on the face rather than the fingers, which will be generally hidden by the adjoining laminates.

DGI has two types of finger joint profiles:

  1. Structural finger joints designed for strength with long fingers and a tip gap to ensure parallel & strong joints. These are used in the structural members such as beams and posts.
  2. Decorative finger joints with aesthetic factors in mind. They have shorter fingers and negligible gaps at the tip.

Advantages of finger jointing laminates:

  • Makes it possible to produce longer than available timber stock, such as structural beams up to 20M long.
  • Improve the mechanical properties of laminates by cutting out timber defects.
  • Improves the appearance of decorative products by reducing the amount of superficial defects.
  • Utilise resources otherwise destined to be too short for quality products.

Below are examples of both decorative and structural finger joints. However, finger joint configurations do change with development in technology. One thing that will never change, is the fact that random sample structural finger joints from daily productions are being tested for its strength and monitored in accordance to stringent Australian Standard.

DENSITY

Density of timber is a measure of weight in kg per cubic metre. The figures provided are based on Air Dried Density where the sample has an average 12% moisture content (MC).

This MC is the average for Sydney, and ultimately all timber will gradually achieve this due to the average environmental humidity prevailing on the mid East coast of Australia. The MC will be lower in Southern states or desert regions, amd higher in tropical areas.

Density is closely related to hardness of the timber.

Generally more dense timbers will have better mechanical properties & will also usually be harder.