FRAMING JOINTS Butt joints
A butt joint is a joinery technique in which two members are joined by simply butting them together. The butt joint is the simplest joint to make since it merely involves cutting the members to the appropriate length and butting them together. It is also the weakest because unless some form of reinforcement is used (see below) it relies upon glue alone to hold it together. Because the orientation of the members usually present only end grain to long grain gluing surface, the resulting joint is inherently weak. To overcome their inherent weakness, butt joints are usually reinforced by one of the following methods:-
DOWEL JOINT
holes in each member into which short dowels are inserted with some glue. The joint is brought together and clamped until the glue has dried. BISCUIT JOINTAs its name suggests biscuit joints are secured with pieces of timber that are in the shape of a biscuit and these pieces of timber help to prevent movement and add strength. To construct these joints you need to use a tool called a biscuit joiner which is used to cut the biscuit shaped holes in the wood. Half lap jointsHalf lap joints (or halving joints) are so called because both members of the joint are halved in thickness so that the faces of the finished assembly are flush with one another TEE HALF LAP JOINTThis joint consists of a pin on the end of one piece which fits into a socket in the other piece.
CORNER HALF LAP JOINTIt is used where the pieces meet at their ends to form a corner.
CROSS HALF LAP JOINTIt is used where two members cross each other.
STOPPED TEE HALF LAP JOINTIn this joint the socket is stopped away from the edge and the pin is cut short, so that in the assembled joint the end grain of the piece is not seen
Other half lap joints include: DOVETAIL HALF LAP JOINT MITRED HALF LAP JOINT
SCARFED JOINT Bridle JointsThe bridle joint is another form of framing joint. It is a stronger joint than the half lap joint as it has a larger gluing area.
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