%20203x100.webp)
Datum
A theoretically exact reference point, axis or plane from which dimensions and GD&T controls are established.
Rapid Prototyping Glossary
D
Definitions for commercial rapid prototyping, production, machining, casting, moulding, finishing and inspection terms.
Datum target
A specified contact point, line or area used to establish a datum on an imperfect real part.
De-gating
Removing the gate remnant from a moulded or cast part.
Debinding
The removal of binder from a printed or moulded green part before sintering.
Deburring
The removal of burrs and sharp edges from machined, cut or moulded components.
DED
Abbreviation for directed energy deposition.
Deep-hole drilling
A drilling process for holes with a high depth-to-diameter ratio, often requiring special tooling, coolant delivery and chip evacuation control.
Defect
Any unwanted imperfection in a moulded part, such as flash, sink marks, short shots, warpage, weld lines or burns. Defect analysis links the visible issue to tooling, material or process causes.
Degating
The operation of removing the gate vestige or separating the part from its runner system after moulding. Degating may be manual, trimmed, sheared or automated depending on gate style.
Delamination
Layer separation within a printed, laminated or composite part, usually caused by poor bonding or stress.
Density
Mass per unit volume; also used in additive manufacturing to describe the completeness of fusion in a part.
Depowdering
Removing unfused or loose powder from an additively manufactured part after printing.
Design for additive manufacturing
DfAM; design methods that exploit additive capabilities while respecting process constraints.
Design for assembly
DFA; design practice aimed at simplifying assembly, reducing part count and lowering production cost.
Design for manufacturability
DFM or sometimes DfM; the practice of designing a part so it can be machined or otherwise manufactured more reliably, quickly and economically.
Design for manufacture
DFM; designing parts so they can be produced reliably, economically and at the required quality.
Design freeze
The development stage at which the part definition is controlled and only formal changes are allowed.
Design of experiments
DoE; a structured statistical method for testing variables and understanding process behaviour.
Design verification
Testing and analysis performed to confirm that a design meets its specified requirements.
Detailing agent
In Multi Jet Fusion, the jetted agent used to sharpen edges and control heat spread so fine details remain better defined.
DFM
Design for manufacturability; a shorthand used in CNC and broader manufacturing to describe design choices that reduce machining difficulty, cost and risk.
Die casting
A metal-forming process in which molten metal is forced into hardened steel dies, typically for repeatable production of complex non-ferrous components.
Digital ABS
A PolyJet digital material blended to emulate some of the stiffness and toughness associated with ABS.
Digital light processing
DLP; a vat-photopolymer process that cures an entire resin layer at once using projected light rather than a scanning laser spot.
Digital light synthesis
DLS; a commercial resin-printing process family associated with Carbon DLS.
Digital materials
Composite photopolymer materials created in PolyJet or similar systems by blending two or more base resins during printing.
Direct energy deposition
DED; an additive process in which focused thermal energy melts material as it is deposited.
Direct metal laser sintering
DMLS; a metal powder-bed process in which a fibre laser selectively fuses layers of metal powder.
Directed energy deposition
DED; an additive metal process that feeds powder or wire into an energy source such as a laser or electron beam, often for repair or large metal builds.
Directional sanding
Sanding in a controlled direction to achieve a consistent grain or cosmetic finish.
Dissolvable support
Support material designed to be removed in a solvent or other controlled bath rather than by breaking.
DLP
Digital light processing; a vat-photopolymer method that cures each layer using projected light rather than scanning a laser spot.
DLS
Digital Light Synthesis; a commercial resin-printing process family associated with Carbon DLS.
DMLS
Abbreviation for direct metal laser sintering.
Dog-bone fillet
A relieved internal corner added to CNC-milled pockets so a square mating part can seat correctly.
Dogbone fillet
A relieved inside corner feature added to milled pockets so square-edged mating parts can fit despite round cutter geometry.
Down milling
Alternative term for climb milling, where cutter rotation and feed direction act in the same general direction at the point of cut.
Draft angle
A taper added to moulded features to help parts release from the tool without scuffing or damage.
Draft resin
A fast-printing photopolymer resin intended for concept models and quick design iterations rather than the highest possible final finish.
Drill jig
A fixture that guides a drill or other tool to ensure consistent hole position and orientation.
Drilling
A machining operation that creates or enlarges a round hole using a rotating drill, often followed by reaming, tapping or boring where tighter requirements apply.
DRO
Digital readout; an electronic display showing axis position on manual or CNC machines.
Dry film lubricant
A solid lubricating coating, often used where oils are undesirable.
Dry machining
Machining performed without flood coolant, often relying on tool coatings, air blast or minimum-quantity lubrication instead.
Dry-blast glass bead
A blasted texture created with glass bead media; commonly referenced in SPI and VDI mould-finish descriptions for satin or matte surfaces.
Drying hopper
Heated equipment used to dry hygroscopic plastic pellets before moulding.
Durometer
A hardness scale commonly used for elastomers and soft polymers.
Dye penetrant inspection
A non-destructive test in which penetrant dye reveals surface-breaking defects.
Dyeing
Adding colour to a part surface, often used for porous nylon parts produced by SLS or MJF.
Dynamic balancing
Correcting mass imbalance in a rotating component so it runs smoothly at speed.