Product Design Glossary

This pages privdes a list of commonly used Product Design Terms :

  • 2D – Two-dimensional. Usually used in context of CAD or image.
  • 3D – Three-dimensional. Usually used in context of CAD or rendering. A 3D rendering is a 2D image generated from a 3D CAD model
  • Aesthetics -The look and feel of a product.
  • Animation – Visualisation comprised of moving images, usually created from 3D CAD. Allows a ‘movie’ of the design without needing physical samples.
  • Anthropometrics – Study of measurements of humans. Used to inform ergonomics.
  • Assembly -A collection of parts and sub-assemblies.
  • Bevel -See Chamfer.
  • Bill of materials -A table of components used in an assembly and values associated with them. Eg Quantity,Weight, Material.
  • Blend -See Fillet.
  • Brief -The documentation defining the specifications and standards which the final design outcome must meet.
  • CAD -Computer Aided Design.
  • CMF – Colour, material, finish.
  • Cavity -The part of an injection moulding tool which forms the outside of a part.
  • Chamfer -An angled cut at a corner or edge.
  • Coil -A spring like curve defined by pitch height and revolution.
  • Component – Part or sub assembly within an assembly.
  • Concept -A vision of how a product could be, often explained with hand sketches and rough models.
  • Constraint – See Relation.
  • Core -The part of an injection moulding tool which forms the inside of a part.
  • Crosshatch -A pattern of parallel lines applied to an area on a drawing such as section-views.
  • Cut -A feature which removes material from a part.
  • Cycle time -The time it takes to mould one part
  • Detail view -A portion of a view on a drawing, usually larger scale than the view it originated from.
  • Dimensional tolerance -See Tolerance.
  • Direction of pull -The direction a mould tool opens in relation to the part it makes.
  • Draft -The angle measured between a face and the direction the mould tool opens.The bigger the draft, the easier a part can be manufactured.
  • Drawing -2D representation of a 3D part or assembly. Used to fully and clearly define requirements for manufacture.
  • Edge -Outer boundary of a feature.
  • Ejection points -Areas on a part which are used by ejector pins to push the part out of a mould tool.
  • Engineering drawing – See Drawing.
  • Ergonomics -Designing a product around the physical properties of its user.
  • Exploded view -A view of a product with all its components separated, usually to show how it is assembled.
  • Extrusion -A linear projection of a shape which either adds or removes material within the projected shape.
  • Face -See Surface.
  • Fastener – Component which mechanically joins two or more objects together. Eg Screw, Staple, Nail.
  • Feature – An individual shape contained within a part.
  • Fillet -A rounded corner or edge.
  • Flash -Excess plastic on a part found when the mould tool did not seal properly when the part was being moulded.
  • Flow marks -Visible marks left on a part by the moulding process.
  • Gate -The point from which molten plastic is forced into the mould. Gates often leave a visiblemark where the part is cut from the moulding machine.
  • Hatching – See Crosshatch.
  • Helix – See Coil.
  • Hem – Sheet metal edge that is folded over. Eg closed, double or tear-drop hem.
  • Hole table -A table listing hole sizes and locations on a drawing
  • Injection point – See Gate.
  • Intellectual property (IP) – Characteristics of a design the owner may wish to protect from unauthorised use. Strategies include trade secrets and formal, legal IP protection such as utility patents & design registration.
  • Interaction design – The consideration and design of the way users will interact with a product.
  • Interference -The area in which two or more parts obstruct each other when positioned in an assembly.
  • Knit lines – During the injection moulding process, when the flow of material splits, a line where the material meets back up again is often visible.
  • Line of draw – See Direction of pull.
  • Loft – A part feature created by transitions between two or more profiles.
  • Lug – A small extrusion.
  • Manufacturing tooling – See Mould tool.
  • Mate -Geometric relationships between components in a assembly. Eg Perpendicular, Tangent, Coincident.
  • Mould tool – Tooling used to produce plastic parts, usually made from hardened steel or aluminium.
  • Mould flow analysis – Computer simulation which predicts how molten plastic will fill a mould tool during the injection moulding process. It can be used to identify potential manufacturing issues.
  • Multi-cavity mould -A mould with multiple copies of the same part.
  • Nesting -Placing components within one another to reduce cost when being rapid prototyped.
  • Part – A 3D object made up of features. In an assembly it can be referred to as a component.
  • Parting line – The line around a part where mould pieces come together. There is often a visible line left behind.
  • Prototype – Functional model of the proposed design.
  • Rapid Prototyping (RP) – Various technologies for producing a prototype directly from 3D CAD data which produce a result far more quickly (typically within a couple of days) than traditional model-making.
  • Recess – An indentation into the body of a part.
  • Rendering – A product image generated either from a computer model, or by hand.
  • Research – May be undertaken at different times in a project, for different reasons. Common types are user research, competitor research, and research into materials and process.
  • Revolve – A feature created by revolving a sketched profile around a centreline.
  • Rib – A reinforcing feature of a moulded part.
  • Round – See Fillet.
  • Screw boss – A feature designed for a screw to be fixed into.
  • Section view – A drawing view created by cutting through another drawing with a section line.
  • Short shot – A part that wasn’t completely filled with resin, causing missing features.
  • Shrink – When a part is reduced in size as it cools after moulding. The shrink rate will be adjusted for based on material selection.
  • Sink marks – Unwanted depressions in the surface of a part which occur in thick sections of a part.
  • SLA – See Stereolithography.
  • SLS – Used to create components with realistic movement
  • Spline – A smooth 2D or 3D curve defined by a set of control points.
  • Sprue – The passage through which liquid material is introduced into a mould during casting or moulding. Material in the sprue will solidify and need to be removed from the finished part.
  • Stereolithography – A rapid prototyping technology used to create components with a realistic look.
  • Sweep – A feature created by moving a profile (section) along a path.
  • Tangent – Two lines or bodies which have point in the same direction where they meet.
  • Third angle projection – The convention used for displaying drawing views used in the UK.
  • Title block – A table located in the bottom right corner of a drawing which contains sections for providing quality, administrative and technical information. Eg Drawing number, material, finish.
  • Tolerance – The amount that part dimensions can be wrong by without affecting the performance. Each dimension can have its own specification for tolerance.
  • Undercut – A feature that cannot be moulded using a simple open and close mould tool because it would prevent the tool from re-opening. Side action features in the tool would be required.
  • Warp – A distorting of part dimensions as the part cools. The addition of ribs can help prevent this.
  • Weld lines – See Knit Lines.