What You Need To Know: Pinless Moisture Meter

Carpenters at some home industries or even medium-sized factories may rarely use pinless Moisture Content (MC) meter in their wood processing facility.

Wood Density: An Overview

Density is mass per unit volume, and wood density relates to the amount of wood and its substance without water or air inside.

What Cause Rusty Hinges On Your Furniture

Problem of rusty hinges are often invisible when you buy a new outdoor furniture while it's packed. Usually you will see it after you unpacked it...

EUTR 2013

The European Union Timber Regulation (EUTR) has been effective since March 3, 2013 to prevent the use of illegal wood in the products sold within the European market.

Wood Physical Properties

Wood has unique physical properties compared to other materials. Those bring advantages and characteristics that cannot be found in other types of materials.

14 September, 2021

Different Logs Cutting Methods Used At The Sawmills

To get timber or flat boards you have to cut a round log. And to do so there are several methods to get the most of it on its grain appearance, best quality of timber or to get the best yield. Using bandsaw is quite common at larger sawmills, and smaller sawmill or logs normally using circle saw.
Some manufacturers prefer to buy sawn timber (dried or not dried), or not invest a sawmill facility in their factory. But larger manufacturers normally will install sawmill in-house for them to have better control on their yield and material cost and to have timber dimension just as they need.

There are mainly 3 ways to cut logs:

Plain Sawn
The most commonly used by sawmills and the best yield can be achieved. It is the most efficient way and works for any shape of logs (round or oval). The cutting is just one or two direction along the log from one end to another. And it can be done by a vertical or horizontal bandsaw machine.
The timber grain mostly from tangential side, less straight and more curvy (U-shape) and the wood shrinkage is bigger on its width side.

Quarter Sawn
This method produces less yield and less efficient. The log is sawn into 4 quarter in the middle, and cut into boards several ways along the logs (see the figure). The grain appearance is a mix between radial and tangential. You can have more straight grain timber using this method.

Rift Sawn
The least yield and the most inefficient sawing method. It produce a lot of waste but the quality of the timber is the best among other methods. Riftsawn cutting angle are mostly around 40-60 degree direction, aiming only radial cuts. It results straight grain timber and very low wood shrinkage ratio.

Some people find straight grain more attractive. And as it is less efficient, it becomes more expensive compared to timber with curvy (U-shape) grain.

05 September, 2021

Wood Physical Properties

Wood has unique physical properties compared to other materials. Those bring advantages and characteristics that cannot be found in other types of materials.

Wood Color
Wood color is very important for decorative use of the product. Dark or lighter colors will determine which wood species to use for product's exposure or finishing type to use. At certain wood species, such as Acacia, Teak, or Mahogany, the sapwood color is lighter than the heartwood. Wood color will be darker than its original color when it's wet.

Odor and Taste
The odor and taste of wood is influenced by the natural resin content in it. Teak wood, for example, has a very unique odor because of its natural oil content. This odor and taste is usually only found in timber that freshly split or cut. After a while the odor and taste will fade.

Wood Grain
Wood is formed from thousands of pores that are composed during the growth of tree. The shape and pattern of timber grain depend on the method of sawing. The grain direction in the radial cut tends to be straighter, and the tangential cut direction tends to be more wavy. The growth rings also determines the shape and direction of the wood grain.

Wood Density
Wood density is related to the amount of wood and its substance in wood without water or air. This refers to the amount of wood per unit, divided by the volume of wood. Wood density is measured in kg/m3 or grams/cm3. Refer to the article about Wood Density: An Overview for more detail.

Wood Hardness
The cross section of wood has higher hardness level than the other side (tangential or radial) because of the direction of the wood grain or pores. And wood with high density can also be interpreted as hard wood.

Moisture Content
Trees have pores which one of the functions is to channel water and food sources from the roots to other parts of the tree to grow. These pores allow wood to expand or shrink according to the water content. The moisture content in the wood is affected by the humidity of the environment around the wood.
If the environment humidity is high, the moisture content in the wood will increase, and will make the wood expand. If the humidity of the environment is lower, the moisture content in the wood will also decrease and it makes the wood shrink. The level of wood moisture content will reach its equilibrium point between 8-12%. It's also called Equilibrium Moisture Content (EMC).

Wood Shrinkage
Wood can have a shrinkage, if the dryness of the wood is below the EMC. The wood will shrink and change its shape. In an extreme shrinkage situation, the size of the wood can change by up to 8%.

Thermal and Electrical Conductivity
Wood has the ability to transmit heat and electricity with relatively very small power, especially when the wood is dry under its EMC. Electricity and heat are basically easier to move through water, and if the wood moisture content is very high, then the conductivity of heat and electricity will be higher.

03 September, 2021

Wood Shrinkage Explained

A basic knowledge you must know before doing some wood works. Wood shrinkage is one of wood physical properties. It plays important roles in the utilization of wood. Wood is hygroscopic, it has the ability to absorb and release moisture. The shrinkage occurs at perpendicular to grain (cross-section dimension), not at longitudinal to grain.
As a rough rule-of-thumb, wood shrinkage is about 8% tangential direction, 4% radial direction, and 0.1% longitudinal direction from fresh cut/green to ovendried condition. Higher density (heavier) wood generally shrink more than lower wood density (lighter).

Wood shrinks because it loose moisture (water content) as it dries. The shrinkage at tangential cut is bigger than shrinkage at radial cut.

A fresh cut wood from trees initially contents high moisture because a living tree moves water from root to branches and leaves. Wood adapts its environment moisture by either releasing or absorbing moisture. But the normal environment is not enough to release wood moisture into its Equilibirum Moisture Contents (EMC). Most wood manufacturers use kiln to dry the timber. It uses heat and ventilation system to control the chamber humidity to release wood moisture contents.
Sawmills use different cutting method to achieve the maximum yield of timber or to get the best quality of timber toward shrinkage.

One way to avoid cumulation shrinkage (on wood flooring for example), determine the timber position and estimate wood shrinkage direction based on cutting method.
Under certain condition, wood shrinkage will create gap between timber or pressure of deformation.

25 August, 2021

8 Most Common Types of Wood Corner Joints

From traditional carpenters to the most modern machineries are using these common woodworking joints as furniture construction or other wood products for corner connection. You can find it in every single wood products at home.

1. Butt Joint
This joint is very simple just to connect the other wood end to the width or thickness side of the other piece. No need further works, just a smooth cut and to reinforced it by glue, nails, or screws.
Butt join has low strength, it is typically used for frames or trim that don't make the structure of product. 

2. Miter Joint
People use this joint when they do not want to see the wood end at the joint. It has better advantage compared to Butt joint, and gives bigger surface to apply glue on the connection. The strength is still low so it needs reinforcement by adding nails, screws, or staples. 

3. Half-Lap joint
It is a common join when another piece need overlap the other piece to support. Mostly the overlapped piece will have smaller dimension on top of the main piece. This join is commonly used for rails under the bed, open kitchen rack, or main frame of roof top.

4. Bridle joint
Very common joint used in the furniture frame and other frames products. It give nicely artistical impression but requires precise and high technique of woodworking. The line at the joint must be clean and accurate to have a good grab and sufficient surface for the glue.
This joint is more suitable for indoor products with less exposure to extreme weather.

5. Tenon and Mortise joint
This joint similar to Bridle joint at a piece (the tenon), and there is a hole (not go through) at another piece called mortise. The advantage of this joint compared to Bridle joint that the wood edge is hidden. It gives 2 impacts on the construction, bigger amount of glue can be applied and better appearance of the joint.
Traditional carpenter used to choose this joint instead of Bridle join because even if the mortise dimension is not precise enough, it will not be visible and even it gives additional space for more glue amount. 

At some automatic machine, the tenon will be rounded and bevelled.

6. Box joint
Some also call this finger joint and mostly applicable for wide timber joints. Basically it's an extension of Bridle joint to adjust the width. Esthetically this joint has a nice looks, and technically simple to do and strong. Very suitable for drawer box construction or other wide board made of solid wood or plywood.

7. Dovetail joint
Dovetail joints is similar to Box joint with a little different angle. It works better for hard wood, higher density wood. Even without additional glue as reinforcement, this joint have a strong bond and wood pieces are irremovable at one direction against the tail angle.
This construction consists of interlocking pins and tails in trapezoidal shapes. This joint exposed typically shows the expertise of craftsmanship.

8. Dowel joint
Dowel joint used to be popular because its simplicity of process just by a drilling machine. As it does not give enough strength at certain position and the work to produce the dowels are not anymore efficient nor practical. The wood dowel is normally specially crafted that it will expand when applied with glue and make the joint tightened.
For knock-down system furniture this joint still the favorite for the convenience of customer assembling.

16 August, 2021

EUTR 2013

The European Union Timber Regulation (EUTR) has been effective since March 3, 2013 to prevent the use of illegal wood in the products sold within the European market, especially in EU member countries. Now, after the Brexit, the UK is likely to make its own regulations regarding the distribution of illegal timber. Let us recall what are the problems caused by illegal logging activities for humans.

There are 3 main things, the first one is the economic problem. Illegal logging causes most of the parties to lose their economic income and the legitimacy of those who carry out illegal logging activities is doubted. The second is the environmental problem, where illegal logging activities result in a reduction in the area of forest land that functions very vitally to the changes of weather and the living creatures in it.

And the third is the social problem, its relationship with the lives of local communities around the forest and the potential for conflict with certain parties. That is why the European Union seeks to stop illegal logging activities in the country of origin of the timber.

Who get the direct impact of this new regulation? The target of this regulation is companies that intend to sell wood products to EU countries, means only companies with retail networks in Europe are directly affected. However, these companies will systematically give the same requirements to the exporter and it also means that furniture factories are required to have compliance with these regulations. Products included in this regulation are most of furniture products made of wood or other products made of wood (paper, kitchen utensils, decorations, etc.).
However, it does not include products that use recycled materials such as wooden pallets, bamboo and rattan. Paper with printed images or writings is also not included.

If you have a furniture factory, it is recommended to create an internal policy to purchase raw material with clear and clean traceability documents showing the logs are coming only from managed forests. It does not mean you have to buy certified wood from certified forests (FSC, PEFC, etc) but the document must show that the material are legally purchased. This is a part of the obligation to undertake DDS (Due Diligence System) for a factory as one of the 'operator' who place wood products into the market.

A DDS contains three elements:
1. Access to the information
Factory (operators) is adviced to have evidence of the information required but it is not obligatory; it suffices that they have access to it and are able to provide it upon request by the competent authorities (e.g. their supplier sends the necessary documents when so requested).
2. Risk Assessment
This step requires operators to evaluate, based on the information they have collected, if their products have been produced in compliance with the laws of the harvesting country. The following questions (risk assessment criteria) must also be replied:
3. Risk Mitigation
Factory to take risk mitigation measures to minimise that risk effectively. Measures may range from requiring additional information or documents from suppliers and/or third party verification to shifting to more reliable sources.