Dowel Joint

Dowel joints are very strong and attractive if they are, like all other joints constructive well. Dowel is also very useful for greatly increasing the strength of weaker woodwork joints such as the butt joint.

This type of joint is secured with an adhesive and a small piece of dowel. Construction also requires nothing more than a drill and some accurate markings.

To achieve perfect markings a special measuring tool can be used to measure the position of the holes for the dowel to be inserted.

The tool is called a dowel centre and they are placed in a predrilled hole to create an accurate mark on the other piece of timber where the next hole will be drilled.

The dowel joint is assembled the same way you would screw a regular joint together only pieces of dowel are glued and inserted into holes instead of screws. By using pieces of dowel over screws the joint becomes much stronger and can be turned into an appealing feature.

Step 1: You need to calculate the size of dowel suitable and then mark where you are going to make the joint.

You can either mark the position of the joint and where to drill the holes with a ruler or you can drill a hole in one piece of timber and use a dowel jig to mark the second piece and this should be a very accurate method if done correctly.

Step 2: The next step is drilling the holes for the dowel but remember to only drill as far as you need to fit your dowel and to use a drill bit the same size as the dowel.

You can drill the holes with a cordless drill or a pedestal drill but the pedestal drill is more accurate so it is usually the best option.

Step 3: Now insert the dowel into one of the pieces of timber and insert the other piece on the other end of the dowel. Bond the joint together with a strong glue and clamps can be used but are not usually needed depending on the size if the timber.

Tip: You can drill a hole all the way through one of the pieces of timber and insert longer dowel but using this method will mean that the dowel will be visible in the back of one of the pieces of timber.

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Mitre Joint

The mitre joint is another one of those woodwork joints that is almost as easy to construct and make as a butt joint. Even though it is similar to a butt joint this joint is marginally stronger and has much greater aesthetics.

The reason why this type of joint is stronger and more appealing than a butt joint is because the ends are cut at a 45° angle and then glued together, this creates better surface area for adhesive to be applied while also concealing the end grain giving it a nice flush look.

The best results for these joints are achieved by cutting the angle of the joint with a drop saw instead of a hand saw, this creates very straight and neat edges.

The mitre joint is very common on picture frames because there is no end grain showing and they don't require much holding strength. Sometimes a frame made from this type of joint is used to attach or cover the edges of wood panelling.

Step 1: The first thing you do is draw 45° line where you want your mitre joints to be.  If you have a drop saw or sawing block you should not need to draw the lines.

Step 2: Now either cut along the lines with a hand saw or drop saw but remember if using a drop saw you can usually adjust it to a 45° angle and if using a sawing block it should have a 45°  slot for mitre joints.

Step 3: After the joints have been cut check them to see if they are accurate and then join the joint together with an adhesive and leave it to dry.  If the joint is not reasonably accurate or if ti is cut at the wrong angle the ends will not fit together properly.

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Plywood

Plywood is another manufactured board that it is made from layers of solid timber veneer that are usually about 3 millimetres thick. Because it is made in layers it is incredibly strong but also light in weight.

The interior layers of these boards are usually made from an inexpensive wood while the outer veneer layers are made from more expensive timber to give the board a nice wood grain appearance.

This type of board is manufactured from layers of veneer that are glued together and compressed under heat, they are then cut into appropriate sizes. With each new layer of veneer added the grain is rotated at 90 degrees each time, this is done to maximise the boards strength and to prevent warping and twisting.

This manufactured board is used as a more affordably option to solid timber or as an alternate to other manufactured boards. You are most likely to see this wood used in places such as school desks, furniture, wood panelling and some flooring although usually only the faces are shown due to the unattractive look of the edges.

Advantages:

• Very strong
• Light
• Resists cracking, bending, warping, and shrinkage
• Can be made from most timbers to increase aesthetics
• Good for wood panelling

Disadvantages:

• Edges of board are unattractive and can't be covered
• Not suitable for many joints
• Still may contain natural defects such as knots due to the sheets of veneer

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