Joints

CROSS HALVING JOINTS

Cross halving joints are probably the most simple of joints to mark out and cut. They are used whenever it is necessary to join two pieces of wood that cross over each other. Sometimes these joints can be seen on the strengthening rails of tables and chairs.
The animation below is a good example of ‘Halved Joint’. In this type of joint one piece crosses over the other part. If you look closely you can easily see that a part of each piece of wood has been cut away so that they both fit together when they are finally glued together. Notice there are different names for each halving joint.
A cross halving joint is a common woodworking joint used a method of fixing two pieces together. It is often used as a joint for furniture and other wood based items. Two pictures below show the joint disassembled and assembled. Complete the two sketches and add shade / color.

Tee Halving, Dovetail Halving and Half Lap Joints

A range of halving joints exist to suit different designs. For instance, the dovetail halving joint shown below can be used where great strength is required. A joint such as this is very difficult to pull apart because of the dovetail shape of one of the pieces. However, marking out and cutting the dovetail halving joint is much more difficult than a simple tee halving. The tee halving and half lap joints can be used where great strength is not required, they are also much easier to mark out and cut.
DOVETAIL HALVING
HALF LAP
TEE HALVING

Bridle Joints

These two ‘BRIDLE JOINTS’ are used when a light frame is needed and strength is not the main requirement. For example, a picture frame. One part of the joint fits into the other part and is glued permanently in position. The angled bridle joint can be used a a substitute for a mortise and tenon joint, again if strength is not important.
ANGLED BRIDLE JOINT
PLAIN BRIDLE JOINT   One of the most common joints used for joining the rails and legs of tables, chairs and other type of furniture is the Mortise and Tenon joint. A large range of mortise and tenon joints exist and the most simple of these is shown below. THE PLAIN MORTISE AND TENON JOINT   The tenon is the part that fits into the mortise. A glue such as PVA or cascamite is applied before the joint is pushed together. Clamps are used to hold the joint firmly together, usually for twenty four hours. This type of joint could be used to join the legs and rails of a table together because they are strong effective permanent joints. If a good glue such as PVA or Cascamite is used the joint would be very unlikely to break apart. Wedged Mortise and Tenon Joints

(The two small thin wooden pieces differentiate common mortise and tenon joints from wedged ones, wedged ones have the two small thin wooden pieces, thats why its called wedged) The wedge is inserted inside  the tenon at the time of building.

DOWELLED MORTISE AND TENON JOINTS

This is another example of a mortise and tenon joint. However, in this example a piece of dowel rod is drilled through the mortise and the tenon. This helps keep the joint together even when it is under great pressure. This is used as a joint on chairs and other pieces of furniture so that the joints do not break apart when extra weight is applied. If a joint of this type is cut accurately, glue often is not needed to hold the parts together. When the dowel rod is 'tapped' into position the tenon is pulled into the mortise, creating a very tight joint.

Below another way in which dowels can be used to form a joint. Modern pieces of furniture are often jointed in this way. It is a permanent method but it is not the strongest joint as the parts can eventually pull apart, especially as the joint becomes old. However, it is a quick  to do and saves precious time. Modern glues that are very strong have meant that this joint is often used to quickly fix parts together.

this wooden nail figure hence makes it a dowelled joint. Holes are drilled on both, the tenon and mortise so they can join each other. Try square and a marking knife will mark out the joints, chisel can break the surface of the wood, waste wood removed with the handle of the chisel. DOUBLE MORTISE AND TWIN MORTISE JOINTS tenon has two heads in double, tenon has a c type cutout in twin, yahoo (link points to image) search image if needed,  however, such detail shouldn't prove to be necessary. Stronger because of more area for glue to be apllied. DOVETAIL JOINTS The ‘DOVETAIL JOINT’ is very strong because of the way the ‘tails’ and ‘pins’ are shaped. This makes it difficult to pull the joint apart and virtually impossible when glue is added. This type of joint is used in box constructions such as draws, jewellery boxes, cabinets and other pieces of furniture where strength is required. It is a difficult joint which requires practice. There are different types of dovetail joint and when cut accurately they are very impressive and attractive. The Lapped Dovetail Joint This type of dovetail joint is often used for drawers where the joint can only be seen from one side. The joint is very strong as are all dovetail joints. This type of joint is sometimes used as the joint for book cases and cabinets. Finger Joints This a good example of a ‘finger’ or ‘comb’ joint. It is ideal for box constructions and is suitable for use with natural woods such as pine and mahogany or even manmade boards such as plywood and MDF. The joint is strong especially when used with a good quality glue such as PVA (woodworkers adhesive) or cascamite. http://technologystudent.com/joints/dove2.htm reference to cut and mark out doubletail joints. (its fairly obvious pencil, try square, tenon saw, coping saw (removes waste wood), chisel to finish the joint and its done).