Blog
Star Rapid’s blog aims to share our hard earned knowledge on manufacturing and product development. We hope these articles help you to optimize your product design and better understand the world of rapid prototyping, rapid tooling, 3D printing and low-volume manufacturing.
Top 7 Advantages to Using CNC Machining for Rapid Prototyping
Rapid prototyping means building a physical model of a new product design as quickly and as economically as possible. Some prototypes will be used merely as cosmetic mock-ups or scale models, while others must meet more demanding performance criteria. Prototypes are...
Why Small Dimensions Are A Big Deal in Manufacturing
Precision manufacturing means consistently producing parts that have dimensions with very fine tolerances, usually measured in microns or 10-6 meters. This is entirely possible when using good CAD/CAM digital equipment and modern, high-speed cutting tools. But there...
6 Great Innovations That Came from the Future
There have always been visionaries able to forecast the future by tracing the arc of the present. Many of them were also great storytellers, and their work has appeared in popular books, films and television shows where it continues to inspire generations of...
What’s New in Personal Flying Machines
Humans have envied the flight of birds for thousands of years and we've been trying to replicate it for just as long. But it turns out that making a personal flying machine is a very difficult engineering challenge, which has kept this dream frustratingly out of reach...
The Top 5 Design Tips for Medical Products
As we all know, devices used in medicine and healthcare must meet the highest standards of performance and reliability. This is as it should be, but medical products are more than merely practical tools or appliances. Although there are many different types and...
The Six Benefits of ISO 13485:2016 For Product Developers
What is ISO 13485:2016? ISO 13485:2016 is a quality system management standard. It's similar to ISO 9001, but has a few more stipulations to help companies meet the more specialized demands that come with making medical components and healthcare related products....
Why Micro Molding Is Ideal for Small Medical Products
Micro molding is a specialized form of plastic injection molding for making parts on a very small scale. How small? Finished components can easily weigh less than 1 g and measure smaller than 1 mm in cross-section. How can this help you? To understand the many...
Six Reasons To Use Vacuum Casting For Medical Products
Virtually all new products intended for the medical industry start out as prototypes. Prototypes are used for proof-of-concept, engineering testing, certifications, benchmarking and as design models. And for this purpose, vacuum casting is the ideal rapid...

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- 2K MoldingA type of injection molding in which two resins with different properties are processed sequentially in separate cavities of a single tool.
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- 3D PrintingAlso known as additive manufacturing, this refers to the production of a solid object by sequentially building up 2D layers of printing substrate.
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- A-SideThe A-Side is often the cosmetic side of the part. This side of the part is usually formed by the cavity or A-plate of the mold tool.
- Additive Manufacturing, AMAlso known as 3D printing, additive manufacturing involves the building of a three-dimensional object by the controlled deposition of two-dimensional layers of substrate. May also involve continuous, non-layering processes. Compare to subtractive manufacturing.
- AddSub®Star Rapid's exclusive hybrid service. This combines the flexibility of additive manufacturing with the precision of traditional subtractive production methods.
- Angle PinA strategically placed inclined pin, designed to retract a sliding core in a plastic injection mold tool.
- AnodizingOne type of surface passivation. An oxide layer on the surface of a part is created by replacing some of the surface molecules with ions from an electrolyte bath.
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- B-SideThe B-side is often the inside or non-cosmetic side of a molded part. This side is usually formed by the core or B-plate of the mold tool in injection molding or pressure die casting.
- BaffleFlat or corkscrew shaped blades of metal inserted into the coolant channels of a mold tool to create a return coolant circuit within that channel.
- Ball Nosed EndmillIn machining, a ball nosed endmill has a semi-circular cutting edge of a single radii.
- Barrel (Molding Machine)Cylinder housing the screw and check ring of a plastic injection molding machine. The barrel is also heated to help melt the plastic resin within.
- BossesProjections or protrusions in cast or injected molded parts.
- BubblersTypically thin, hollow tubes that are fitted into drilled holes of an injection mold tool to supply coolant in narrow or hard to reach areas.
- Build PlatePlatform used in additive manufacturing upon which the layers of the part are built.
- Bull Horn GateA type of submarine gate which gates on a face formed by the parting line.
- Bullnose End MillSimilar to a standard endmill, these cutting tools have radiused corners of a known size.
- Bump OffA shallow undercut area of a molded part that is able to be formed without lifters, sliders or handloads.
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- CADComputer Aided Design. The use of computer software to create 2D and 3D digital models of an object in preparation for manufacturing.
- CAMComputer Aided Manufacturing. Producing objects with computer controlled machine tools using digital data.
- Cascade GatingA type of sequential gating using hot runners, in which a series of gates are automatically activated in succession to fill a mold cavity.
- CavityDepression in a die casting or plastic injection mold tool, usually on the fixed or non-moving side of the mold. Typically forms the outside, convex and cosmetic face of the part.
- Check RingFitted on the end of the screw inside the barrel of a plastic injection molding machine, the check ring acts as a non-return valve allowing correct holding pressures to be reached and maintained.
- Chip SizeThe size of the metal chips that are created during CNC cutting operations.
- Clamp ForceThe amount of pressure applied between the 2 platens of a molding machine.
- CMMCoordinate Measuring Machine. This is a precision CNC controlled measuring device. Using special probes this machine can access and measure part features to a very high degree of accuracy on multiple axes.
- CNCComputer Numeric Control. The precise control of automated machine tools via digital instructions derived from CAD/CAM software.
- Cold SlugSemi solidified plastic material formed at the nozzle opening, blocking the flow of material during plastic injection molding.
- Cold Slug WellA trap placed opposite the sprue in an injection molding machine. Designed to capture a cold slug so that it does not interfere with the subsequent production cycle.
- Compression MoldingType of molding in which the substrate is compressed between two mold halves, to be cured under heat and pressure into the final shape.
- Conformal CoolingThe cooling of a mold tool using internal channels created via 3D printing.
- Cooling TimeA waiting period for die casting or plastic injection molding, allowing the part to solidify within the mold so that it can be safely ejected from the tool without deformation.
- CopolymerA polymer derived from two or more monomers.
- CoreOne half of a typical plastic injection or die casting mold tool. This is the moveable, convex half which in turn forms a concave part surface.
- Core PinA separate, removable insert in a plastic injection mold tool. Used to form a hole, aperture or other feature requiring high precision, or in areas requiring molded features difficult to access by other means.
- Cusp HeightIn machining, the raised areas between adjacent passes of cutters.
- Cycle TimeProduction time required to complete one finished part in a molding operation and prepare for the next injection.
- Cyclic CoolingAn approach to mold temperature control that allows rapid switching between hot and cold circuits.
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- Date MarkingIndexable inserts used to mark the date an item was injection molded.
- DatumA reference point on one or more faces, surfaces or features of a part, from which all other dimensions are calibrated.
- DebossedLetters, logos or other graphic marks molded into a finished part, set below the surrounding surface.
- DelaminationSurface defect of an injection molded part due to the presence of contaminants within the machine.
- Dial IndicatorA visual readout using a rotating dial mounted on a precision measurement gauge.
- Diaphragm GateA variant of the edge gate, a diaphragm gate is used to gate around the full circumference of an internal hole on an injection molded part.
- DielectricInsulating fluid such as de-ionized water, used during electrical discharge machining (EDM).
- DimensionsDimensions are measurable sizes of part features using standardized units.
- DistortionA malformation of an injected molded part due to poor design or process control errors.
- DMLMDirect Metal Laser Melting. A type of powder bed 3D metal printing using a laser to fully melt and bond successive layers of metal powder on a build platform.
- Draft AngleAn angle applied to the design of a surface or side wall of a molded part, allowing it to be removed from an injection mold tool without damage.
- DryerHeated chamber used to remove excessive moisture from plastic pellets of raw material before injection molding.
- DWGFrom "drawing". A common CAD file format.
- DXFDrawing Exchange Format. A common CAD file format.
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- Edge GateIn injection molding, edge gates fill the mold cavity at a location along the split line, usually leaving behind a rectangular witness mark.
- EDMElectrical Discharge Machining. The removal of material from a workpiece using high-powered electrical current.
- EjectionThe forced removal of a cast or injected part from a mold tool.
- Ejector BladeSquare or rectangular pins of different dimensions strategically placed in the mold to push out or eject the formed part during plastic injection molding
- Ejector PinRound pins of different diameters strategically placed in the mold to push out or eject the formed part during plastic injection molding.
- Ejector PlatesTwo-part platen system holding the ejector pins for plastic injection molding tools.
- ElectrodeA sacrificial conductor, usually of copper, which discharges high powered electrical current to erode the surface of a workpiece.
- EmbossedLettering, logos or other features raised from the surrounding surface.
- End MillA cutting tool used in conventional milling. End mills have a flat cutting surface and sharp corners. See ball nose cutters, bull nose.
- EngravingEtching text, logos or other graphical features into a part face with an ultrasonically vibrating stylus.
- EtchSelective patterning or erosion of the surface of a part or mold tool to create a textured effect.
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- Family MoldA multi-cavity mold that creates two or more dissimilar parts for a single assembly.
- Fan GateOne type of edge gate in a plastic injection mold tool design, wider at the parting line of the tool halves.
- FDMFused Deposition Modeling. A variant of 3D printing using plastic filament which is heated to the melting point and ejected from a nozzle in successive 2D layers onto a build platform to create a finished 3D shape.
- FixtureA clamp, vise or other device to hold a workpiece securely while it is being machined.
- FlashIn plastic injection molding, a thin residue of waste plastic extruded from between the halves of a mold tool along the parting line.
- Flow FrontThe leading edge of molten plastic as it works its way through the mold cavity during injection. The front will be the first part to contact the solid walls of the cavity and hence to cool and solidify first.
- Food SafePlastic which has been approved for use in food storage or preparation.
- Forced EjectionEjecting a finished part from a plastic injection mold tool using undercuts instead of ejector pins.
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- G-CodeDigital instructions, usually derived from a 3D CAD file, which control the precise tool path, speed and other customized parameters of CNC equipment.
- Gas TrapPockets or voids in a plastic injection mold tool that trap gas during an injection cycle, caused by insufficient venting.
- GateA channel in a mold tool allowing molten material to flow from the runner to the cavity.
- Gate Freeze Off TimeDuring a plastic injection molding cycle, the amount of time typically available for molten resin to fill a cavity before it begins to cool and harden.
- GD&TGeometric Dimension and Tolerance. This is the industry-standard symbolic language for annotating physical features and allowable variations on engineering drawings.
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- HandloadA manually placed and removed component to allow the molding of undercuts in a plastic injection mold tool.
- Heel BlockAn angled face that engages with a matching angle on the back of a sliding core to hold it in place.
- Height GaugeMeasuring device used to determine the height of a feature relative to a flat, horizontal surface plate.
- HomopolymerA thermopolymer resin derrived from a single monomer.
- HopperDrum or cylinder into which is loaded plastic pellets for injection molding.
- Hot Runner/ManifoldIn plastic injection molding, this is a heated system of channels used to distribute molten resin from the machine nozzle to hot tip locations within a mold.
- Hot SprueA heated, tapered hole in a plastic injection mold tool that allows material to flow directly from the machine nozzle into the mold cavity.
- Hot TipSliding cores in plastic injection mold tools that are actuated with hydraulic power. Compare to manual sliders.
- Hydraulic CoresSliding cores in plastic injection mold tools that are actuated with hydraulic power. Compare to manual sliders.
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- IGESAcronym for Initial Graphics Exchange Specification. This is a CAD file format for 3D data.
- In Mold LabelingDate stamps, material codes or other information applied to a part during the molding process via customized molding inserts.
- InfillDuring additive manufacturing, infill is additional material added between layers to fill any gaps or voids left by the printing process.
- InjectionMolten thermoplastic or thermoforming resin forced into a mold cavity under pressure.
- Insert MoldingPlastic injection molding around the circumference of a metal insert.
- International Standards OrganizationOrganization that establishes consesus-based, market-driven standards applying to a wide variety of industries and services.
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- JettingAn injection molding defect that causes snake-like lines on the surface of a molding. Often caused when material leaves a smaller gate at high velocity directly into a thick section of the part or cavity.
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- Knock BacksA pin inside the plastic injection mold. After the mold is closed, it maintains a consistent gap between the cavity and core which is filled with resin during injection.
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- LatheMachine tool for creating round profiles and cavities with concentric or rotational features.
- Layer HeightAverage thickness of a deposited layer of substrate in additive manufacturing.
- Line of DrawMain direction of motion for opening/closing the halves of a casting or injection mold tool.
- Live ToolingRotating cutting tools mounted in a lathe or turn mill tool turret for CNC machining.
- Living HingeA plastic hinge formed by exploiting the ability of some plastics to bend repeatedly without breaking.
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- M-CodeMachine language for programming auxiliary functions in CNC machine tools. See also G-Code.
- Master BatchHeavily pigmented plastic resin used to add color for plastic injection molded parts.
- Melt TemperatureTemperature at which plastic resin achieves a liquid or molten state and can therefore be molded.
- Metal SafeDeliberately making some high-precision metal parts in mold tools oversized, so they can later be machined down to final dimensions.
- MicrometerPrecise measuring tool providing graduated measurements calibrated in microns.
- Mill TurnA lathe that is fitted with live tooling enabling milling operations to be carried out on turned components.
- Modular Unit DieA holding fixture of standard size which acts as a base for securing mold tools in a plastic injection molding machine.
- Mold BaseCustom core/cavity mold tools are made to fit inside of a mold base, which in turn is placed inside a plastic injection molding machine.
- Mold LocksPrecision machined tapered features on mold tools with male and female halves.
- Mold TemperatureOptimum temperature of a plastic injection mold tool based on the resin compound being molded.
- Molding CycleA molding cycle is composed of the following steps: Close, Inject, Pack, Cool, Open, Eject and Close.
- Multi CavityA pressure die casting or plastic injection mold tool with multiple cavities, for creating more than one part in a given cycle.
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- NominalOf or pertaining to the precise numerical value of a dimension. Usually taken as the reference dimension from which allowable deviation must be made in most processes.
- NozzleFitting in a plastic injection molding machine, used to eject molten resin from the barrel into the mold.
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- O-RingA soft elastomer seal with a circular cross-section.
- OESOptical Emission Spectroscopy. A method of positive material identification (PMI).
- OMOM®One Man One Mold. Star Rapid's proprietary service for fast-turnaround tools created by a single master craftsman.
- Outsert MoldingMethod of plastic injection molding in which the molded material is formed inside of a metal fitting. Compare to insert molding.
- OvermoldingAn injection molding technique that allows a second injection cycle to mold plastic on top of an already molded base material.
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- PackingIn plastic injection molding, a secondary application of pressure to a filled mold to ensure full part density and close dimensional tolerances.
- Parting LineThe parting line is the physical break or split between the two halves of a plastic injection or pressure die casting mold.
- PigmentColoring agent used in plastics, paints, and other raw materials.
- Pin GaugePrecision ground, hardened metal pins of known diameter and tolerance used for measurement.
- Pin PushA defect in plastic injection molding that usually presents as stress marks on the A-surface of the part directly opposite the ejector pins.
- Plastic Injection MoldingManufacturing process using thermoforming plastic resin injected under pressure into the empty cavity of a mold tool to make multiple copies.
- PlattenThe large fixed and moving plates in an injection molding machine. The mold halves are clamped to these plates.
- Positive Material IdentificationPMI. The process for accurately identifying metal and plastic material by directly analysing its molecular or chemical composition and comparing the results against a known sample or database.
- Pressure Die CastingPDC. Technique for creating solid parts by injecting molten metal under pressure into the cavity of a die casting mold.
- Process ControlControlling the parameters of the plastic injection molding cycle to ensure optimal and repeatable part quality.
- Push BacksA pin inside the plastic injection mold. After the mold is closed, it maintains a consistent gap between the cavity and core which is filled with resin during injection.
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- Quality ControlProcesses and procedures for measuring and recording numerical and subjective parameters affecting the visual and physical attributes of a manufactured part.
- QuenchingThis is the rapid cooling of a workpiece to achieve specific material properties such as hardness. Normally part of the heat treatment process of metal used for mold tooling.
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- ResinThermoforming or thermosetting plastic material used for injection molding.
- Return PinsA pin inside the plastic injection mold. After the mold is closed, it maintains a consistent gap between the cavity and core which is filled with resin during injection.
- RibsSupport structures in molded parts, usually placed at right angles to walls or bosses.
- RockwellAn industry standard method for specifying material hardness.
- RunnerFeed channels cut into the faces of plastic injection molds, directing the plastic from the sprue to the gate.
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- Screw (Molding Machine)Long helical gear inside the barrel of a plastic injection molding machine. The screw helps to transport, heat and compress the resin for molding.
- Short ShotAn injection molding defect where material has failed to completely fill the cavity.
- ShotTotal volume of material injected into a mold cavity during one cycle.
- Shot WeightThe total weight of all parts, sprues, runners and gates produced in a single molding cycle
- ShrinkDecrease in volume of material when it transitions from a molten to a solid state. Varies according to the material type and part geometry. Fillers such as glass fiber can also affect shrinkage.
- Shrink FitUsing heat to expand a collet, which then shrinks to form a tight mechanical fit with a cutting tool.
- SLAStereolithography. A 3D printing technique using ultraviolet (UV) light to successively cure layers of light-sensitive liquid polymer and fuse it into a 3D solid.
- Sleeve EjectorA cylindrical ejector pin with a precision bore cut through the center allowing the sleeve to pass over a fixed core pin.
- Slider/Sliding CoreAn automatic mechanism built into an injection mold to form undercuts or holes on the part. The opening and closing action of the mold pushes and retracts the undercut detail using angled pins and wedges.
- SLSSelective Laser Sintering. An additive manufacturing process using a high powered laser to fuse successive layers of powdered metal or plastic into a three-dimensional solid.
- Society of the Plastics IndustryAmerican trade and regulatory organization, recently changed name to Plastics Industry Association. They are responsible for creating a series of standard surface texture gauges for plastic injection molding tools.
- Spark ErosionMethod for removing small amounts of metal from a work surface through a series of high-energy discharges of current from a charged electrode within a dielectric or insulating bath.
- Split LineMark left on a molded part indicating where the two halves of the mold separate or the edges of a sliding core form an undercut.
- SprueThe portion of the runner system between the nozzle of the injection molding machine and the runner system in the mold.
- Sprue BushA bushing in a mold which presses agains the nozzle of the injection machine to give passage to the runner system within the mold.
- Sprue PullerAn undercut opposite the sprue which causes the sprue to be pulled out of the sprue bush ready for ejection.
- STLStereolithography. Original CAD file format developed for the stereolithography additive manufacturing technology invented by Chuck Hull.
- STP/STEPAn ISO-standard data file format for creating and distributing CAD files.
- Stress MarksVisual marks on an injected molded part where unequal heating and cooling during manufacture caused local distortion.
- Stripper PlateMoveable plate used to push molded parts off of a mold core after injection.
- Sub GateA type of gate from the runner sytem into the component which goes below the parting lines, generally into a sidewall of the component, thus giving the advantage of automatic degating during ejection.
- Subtractive ManufacturingConventional manufacturing processes where successive amounts of material are removed from a workpiece with cutting, drilling or grinding tools. Compare to additive manufacturing.
- SupportsLoad-bearing structures added to 3D printed parts to provide stability during the printing process.
- Surface CoatingAn application of material on the surface of a workpiece to alter its physical, chemical or cosmetic properties.
- Surface FinishThe texture of a part's surface, which can be measured as a roughness (Ra) value. Also, a subjective determination of surface appearance.
- Surface PlateA very flat and hard horizontal surface forming the base for measurement, tool setup and layout.
- SurfometerDevice for measuring surface roughness by dragging a sensitive stylus across the workpiece and recording the electronic wavelength so generated.
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- TapMale cutting tool used to create internal threads.
- TextureAn organized and repeating pattern applied to the surface of a mold tool or finished part. Compare to Roughness.
- ThermoplasticsOne group of moldable plastic resins which become molten when heated. Once set, thermoplastics can be re-melted and remolded with the addition of heat, so their physical state is said to be reversible.
- ThermosetOne group of moldable plastic compounds which are comprised of two or more constituents undergoing a chemical change during processing and molding. Once molded, the process is irreversible.
- Three Plate MoldThe third plate creates a parting line that is used for the runner system that allows the gates to be on the upper surface of the component away from of the core and cavity parting line.
- Thumbnail/Toenail EjectorA round ejector pin that overlaps the side wall or edge of the component thus partially contacting the edge of the cavity.
- ToleranceAllowable deviation away from a nominal value.
- Transfer MoldingA molding method using a pre-measured amount of solid or powder material that is placed in the transfer pot then forced from the transfer pot into a closed cavity and core area of a heated mold.
- Turn GateA rotating gate in a multi-cavity injection mold tool which is able to selectively close off different cavities.
- Two Stage EjectionEjection of a molded or die cast part from a mold tool, requiring more than one releasing step per cycle.
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- UndercutA hole or feature in a plastic injection molded part design that is not in line of draw. Typically an undercut will trap the part in the mold if undercut release mechanisms aren't used.
- Undercut Release MechanismA moving component in a plastic injection mold tool to allow the molding and subsequent release of the formed part at the undercut location.
- UV StablePlastic molding resin which is formulated to resist the deteriorating effects of UV light.
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- Vacuum CastingMethod of creating copies of a master pattern, using liquid resin poured into a silicon mold which is then cured in a vacuum chamber.
- Vacuum FixtureHolding fixture for CNC machining making use of vacuum pressure. Often used on thin, flat sheets of material where other clamping methods would be ineffective.
- Vacuum HardeningMethod of heat treating steel alloys within a vacuum chamber to prevent oxidation during the heating cycle.
- Valve GateA mechanical valve used in a hot runner system of an injection mold tool which closes off the gate between injection cycles.
- Vapor PolishingMethod of creating a very smooth surface on some transparent plastics to achieve optical clarity. The surface is melted with a reactive gas to cause it to flow and fill in minute cracks, scratches or voids.
- VDISociety of German Engineers. Comparator templates used for grading EDM surface textures.
- VentOpening in a plastic injection mold to allow air to escape as the cavity is filled.
- Vernier CalliperPrecise measuring device comprised of opposing jaws which slide apart on a graduated beam to provide accurate measurement of length.
- ViceHolding device which clamps the workpiece between opposing faces of jaws mounted on sliding screws to accommodate parts of different sizes.
- Visual Quality StandardVQS. This is the criteria for standard visual inspection of a part.
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- WallVertical structures in molded parts, usually defining the exterior volume of a part cavity.
- WarpDistortion of an injection molded or pressure die cast part caused by unequal cooling rates after molding.
- Water ChannelsFluid passages machined into die cast and injection molding tools, allowing the passage of coolant for temperature control.
- Weld LineVisible mark on a molded part's surface, usually occurring around an obstruction such as a hole or cutout. Formed as a consequence of two flow fronts meeting during the injection cycle and cooling at differing rates.
- Winkle GateSee Bull Horn Gate.
- Wire EDMElectrical discharge machining, using a brass wire as a sacrificial conductor to cut precise shapes through hardened steels.
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- X-AxisOne of three primary axes of movement in a three-dimensional X-Y-Z coordinate system. Generally assumed to be horizontal to the viewer's reference.
- XRFX-Ray Fluorescence. Non-destructive analytical test for determining a material's composition by bombarding the surface with high-energy x-rays and reading the resulting emitted spectra, which is unique for all material types.
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- Y-AxisOne of three primary axes of movement in a three-dimensional coordinate system. Generally considered to be vertical to the viewer's reference.
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- Z-AxisOne of three primary axes of movement in a three-dimensional coordinate system. Generally considered to be towards or away from the viewer's reference.