Parallel and minor axis Pitch circle diameter Angular dimension Internal screw threads External screw threads Tolerances Common Asymmetrical Symmetrical Functional Non-functional tolerance tolerance tolerance tolerance tolerance The Common The The Symmetrical A dimension that A dimension that method shows Asymmetrical method shows is essential to is not essential the upper limit method shows the nominal size the function of a to the function of the size the nominal size and the component or of a component placed above the plus the upper symmetrical or space. lower limit. and lower limits tolerance of the tolerance. expressed as a plus and minus. 3D CAD terms 3D CAD is an important aspect of Graphic Communication and you will be expected to demonstrate skill in using it throughout the Courses. You will be required to answer questions 3D CAD in your exam. You may be using terms pertaining to a specific software platform, however, you should know these generic terms for 3D CAD. These terms can be found in the Course Assessment Specifications for the Graphic Commuication Courses. Candidates and centres should note that these are not the only terms to be covered at these levels. At National 4 and 5 Extrude Revolve Subtract Assembly The term used when a A profile that is Used in conjunction Multiple components 2D profile is pulled rotated around an with features to combined to create a into a 3D shape. The axis. describe material model. term add or subtract being removed from a must be used to 3D model. describe the function of the extrude. Fillet Chamfer Shell Materials A rounded edge A straight edge Used to remove Apply a material to a applied to a corner. applied to a corner. material from the CAD model. This can Can be applied in Can be applied in inside of a 3D model. be used for either the sketch or either the sketch or illustration or to
Parallel and minor axis Pitch circle diameter Angular dimension Internal screw threads External screw threads Tolerances Common tolerance Asymmetrical tolerance Symmetrical tolerance Functional tolerance Non-functional tolerance The Common method shows the upper limit of the size placed above the lower limit. The Asymmetrical method shows the nominal size plus the upper and lower limits of the tolerance. The Symmetrical method shows the nominal size and the symmetrical tolerance expressed as a plus and minus. A dimension that is essential to the function of a component or A dimension that is not essential to the function of a component or space. 3D CAD terms 3D CAD is an important aspect of Graphic Communication and you will be expected to demonstrate skill in using it throughout the Courses. You will be required to answer questions 3D CAD in your exam. You may be using terms pertaining to a specific software platform, however, you should know these generic terms for 3D CAD. These terms can be found in the Course Assessment Specifications for the Graphic Commuication Courses. Candidates and centres should note that these are not the only terms to be covered at these levels. At National 4 and 5 Extrude Revolve Subtract Assembly The term used when a 2D profile is pulled into a 3D shape. The term add or subtract must be used to describe the function of the extrude. A profile that is rotated around an axis. Used in conjunction with features to describe material being removed from a 3D model. Multiple components combined to create a model. Fillet Chamfer Shell Materials A rounded edge applied to a corner. Can be applied in either the sketch or A straight edge applied to a corner. Can be applied in either the sketch or Used to remove material from the inside of a 3D model. Apply a material to a CAD model. This can be used for illustration or to