Topic outline

  • Purpose statement

    This module describes knowledge and skills required to construct joints. It describes the skills, knowledge and attitudes required for the trainee to construct lengthening joints, construct widening joints and construct framing joints.

    Elements of competence and performance criteria

    Unit 1: Construct lengthening joints

    1.1 Appropriate identification of types of lengthening joints

    1.2 Relevant use of procedures of constructing lengthening joints

    1. 3 Appropriate application of test and final assembling

    Unit 2: Construct widening joints

    2.1Appropriate identification of types of widening joints

    2.2 Relevant use procedures of constructing widening joints

    2.3 Appropriate application of test and final assembling

    Unit 3: Construct framing joints

    3.1 Appropriate identification of types of framing joints

    3.2 Relevant use of procedures of constructing framing joints are applied

    3.3 Appropriate application of test and final assembling.

  • Introduction

    Joinery is a part of woodworking that involves joining together pieces of wood or lumber, to produce more complex items. Some wood joints employ fasteners, bindings, or adhesives, while others use only wood elements. The characteristics of wooden joints - strength, flexibility, toughness, appearance, etc. - derive from the properties of the materials involved and the purpose of the joint. Therefore, different joinery techniques are used to meet differing requirements. For example, the joinery used to construct a house can be different from that used to make puzzle toys, although some concepts overlap. In British English usage it is distinguished from carpentry which relates to structural timber work.

    Both of these types of construction utilise a combination of woodwork joints, adhesives, and fittings such as nails and screws.

    • Learning Unit 1 Construct lengthening joints

      LO 1.1 Identify types of lengthening joints

      LO 1.2 Construct lengthening joints

      LO 1.3 Assemble part of lengthening joint


    • Learning Unit 2 Construct widening joints

      Widening Joints are used to make wider boards by joining narrower one edge to edge. Whichever jointing method is chosen, care should be taken to ensure the curve of the Annular Rings is reversed on adjacent boards as shown.

      As timber dries out, its Annular Rings will tend to try and straighten. Reversing their direction in this way minimises the degree to which the widened board will cup or warp.

      Note: Although now almost universally replaced by MDF, solid timber window sills would be positioned 'heart side up'. This ensures that if there is any movement as the Annular Rings tend to straighten, the sill would 'bow' upwards in the centre rather than 'cup' and hold moisture.

      To avoid this problem almost completely, choose boards which have been sliced radially from across the centre of the tree, and whose Annular Rings are therefore close to being at right angles to each face (these boards are known as Quarter Sawn and Rift Sawn - they are much sought-after and will be hard to find!)

      It is important to ensure joining surfaces are straight and square and to arrange boards such that their Grain goes in the same direction - this is so any subsequent planing and finishing is made easier. Check for Squareness by balancing one board on top of another and testing with a straight edge.

      Some planing will be needed after jointing to ensure the finished boards surfaces are flat, so choose boards somewhat thicker than the required finished size to start with.

      This unit has the following learning objectives:

      • LO 2.1 Identify types of widening joints
      • LO 2.2 – Construct widening joints
      • LO 2.3 – Assemble parts of widening joints

    • Learning Unit 3 – Construct framing joints

      LO 3.1 – Identify types of framing joints

      LO 3.2 – Construct framing joints

    • Reference(s)

      https://en.wikipedia.org/wiki/Woodworking_joints

      http://wiki.dtonline.org/index.php/Widening_Joint

      https://baubeaver.de/en/woodworking-joints/

      https://www.britannica.com/technology/joint-carpentry