Introduction
3D printing technology has developed its own specialized vocabulary that can be overwhelming for newcomers and sometimes confusing even for experienced users. This comprehensive glossary covers essential terminology across all aspects of 3D printing—from different printing technologies and hardware components to software concepts and post-processing techniques. Whether you’re just starting your 3D printing journey or looking to deepen your understanding, this reference guide will help you navigate the language of additive manufacturing with confidence.
Core 3D Printing Technologies
FDM/FFF
Fused Deposition Modeling/Fused Filament Fabrication – A 3D printing process that builds objects by melting and extruding thermoplastic filament layer by layer. FDM is the trademarked term by Stratasys, while FFF is the equivalent term used by the open-source community.
SLA
Stereolithography – A 3D printing technology that uses a laser to cure liquid photopolymer resin layer by layer, creating highly detailed and smooth parts.
DLP
Digital Light Processing – Similar to SLA, but uses a digital projector screen to flash a single image of each layer across the entire platform, curing an entire layer at once.
MSLA
Masked Stereolithography – A variation of SLA that uses an LCD screen to mask UV light, selectively curing resin layer by layer. Often used in consumer-level resin printers.
SLS
Selective Laser Sintering – A process that uses a laser to sinter powdered material (typically nylon), binding the particles together to create solid structures without needing supports.
DMLS/SLM
Direct Metal Laser Sintering/Selective Laser Melting – Technologies that use a high-powered laser to fuse metal powder particles together, creating fully dense metal parts.
Binder Jetting
A process where a liquid binding agent is selectively deposited to join powder particles. Unlike SLS, it doesn’t use heat to fuse materials.
Material Jetting
A process similar to inkjet printing where droplets of material are deposited and cured with UV light, allowing for multi-material and multi-color printing.
MJF
Multi Jet Fusion – Developed by HP, this technology uses inkjet arrays to apply fusing and detailing agents across a bed of nylon powder, which is then fused by heating elements.
Hardware Components
Extruder
The component that feeds and melts filament before depositing it through the nozzle. Consists of two main parts: the cold end (feeding mechanism) and hot end (melting and extrusion).
Hot End
The heated portion of the extruder that melts the filament before extrusion. Typically includes a heater block, heat break, and nozzle.
Bowden Extruder
An extruder setup where the motor and feeding mechanism are separated from the hot end by a PTFE tube. This reduces moving mass on the print head.
Direct Drive Extruder
An extruder design where the motor and feeding mechanism are mounted directly above the hot end, reducing filament travel distance.
Nozzle
The component at the tip of the hot end with a small opening through which melted filament is extruded. Common sizes range from 0.2mm to 1.0mm.
Build Plate/Print Bed
The flat surface on which the 3D print is built. Can be made of various materials including glass, aluminum, or flexible steel sheets.
Heated Bed
A print bed that can be heated to improve first layer adhesion and prevent warping, particularly important for materials like ABS and PETG.
Stepper Motor
A brushless DC electric motor that divides a full rotation into equal steps, allowing precise control of position. Used to drive motion in the X, Y, Z axes and extruder.
End Stop
A sensor that signals when an axis has reached its limit of travel, used for homing the printer.
Linear Rail
A precision motion system consisting of a rail and bearing block that provides smooth, accurate movement with minimal play.
Lead Screw
A threaded rod that converts rotational motion into linear motion, typically used for Z-axis movement.
Belt
Typically made of rubber with fiberglass reinforcement, belts transfer motion from stepper motors to the print head and/or bed. Common in CoreXY and Cartesian printers.
Frame
The structural skeleton of the printer that provides stability and supports all other components.
Enclosure
A cover that surrounds the printer to maintain consistent temperature, reduce drafts, contain fumes, and minimize noise.
Cooling Fan
Fans used to cool the extruded filament as it’s deposited (part cooling fan) or to prevent heat from traveling up the filament path (heat sink fan).
Mainboard/Controller Board
The electronic brain of the printer that interprets G-code and controls the motors, heaters, and other components.
Printing Materials
PLA
Polylactic Acid – A biodegradable thermoplastic derived from renewable resources like corn starch. Known for ease of printing, low warping, and good detail.
ABS
Acrylonitrile Butadiene Styrene – A durable thermoplastic known for its strength and heat resistance. Requires higher print temperatures and often an enclosure.
PETG
Polyethylene Terephthalate Glycol – A modified version of PET with added glycol, combining the strength of ABS with easier printing properties similar to PLA.
TPU/TPE
Thermoplastic Polyurethane/Thermoplastic Elastomer – Flexible filaments with rubber-like properties, used for prints requiring elasticity.
Nylon
A strong, durable, and somewhat flexible material with excellent layer adhesion and wear resistance. Highly hygroscopic (absorbs moisture).
PC
Polycarbonate – An extremely strong and durable material with high heat resistance, but challenging to print due to high printing temperatures.
ASA
Acrylonitrile Styrene Acrylate – Similar to ABS but with improved UV and weather resistance, making it suitable for outdoor applications.
HIPS
High Impact Polystyrene – Often used as support material with ABS as it dissolves in limonene.
PVA
Polyvinyl Alcohol – A water-soluble material primarily used as support material for complex geometries in dual-extrusion printing.
Resin
Photopolymer liquid that cures when exposed to specific wavelengths of light, used in SLA, DLP, and MSLA printers.
Composite Filaments
Filaments infused with particles of other materials like wood, metal, carbon fiber, or glow-in-the-dark additives.
Software Terminology
Slicer
Software that converts 3D models into G-code instructions for the printer by “slicing” the model into layers and generating toolpaths.
G-code
The programming language used to control automated machine tools. In 3D printing, it contains instructions for movement, temperature, fan speed, etc.
STL
Stereolithography File Format – A common file format for 3D models that represents the surface geometry using triangular facets.
OBJ
A more advanced file format than STL that can include color and texture information.
3MF
3D Manufacturing Format – A newer file format designed to address limitations of STL, supporting color, materials, and other metadata.
Manifold/Watertight
A 3D model property where the geometry forms a complete, enclosed volume without holes or self-intersections, necessary for proper slicing.
Non-Manifold
A model with geometry issues that can cause problems during slicing and printing, such as holes, self-intersections, or reversed normals.
Mesh
The collection of vertices, edges, and faces that define the shape of a 3D object.
Boolean Operation
Operations like union, difference, and intersection that combine or modify 3D models based on their volumes.
Supports
Temporary structures generated by slicing software to support overhangs during printing, designed to be removed after printing.
Infill
The internal structure of a 3D print, typically a pattern like honeycomb or grid that provides strength while using less material than solid filling.
Shell/Walls
The outer perimeters of a print that form the visible surface and provide structural integrity.
Brim
A single-layer extension around the base of a model that increases bed adhesion and helps prevent warping.
Raft
A thick grid printed underneath the model to improve bed adhesion, provide a stable base, and compensate for an uneven build surface.
Skirt
Lines printed around but not touching the model to prime the extruder and ensure filament flow before beginning the actual print.
Print Parameters
Layer Height
The thickness of each deposited layer, affecting print quality and time. Smaller layers give finer detail but take longer to print.
Print Speed
The speed at which the print head moves while extruding material, typically measured in mm/s.
Travel Speed
The speed at which the print head moves when not extruding material.
Retraction
The pulling back of filament to prevent oozing or stringing when the nozzle moves without extruding.
Flow Rate/Extrusion Multiplier
A percentage adjustment to the amount of material extruded, used to fine-tune extrusion for specific materials or printers.
Nozzle Temperature
The temperature to which the hot end heats the filament for extrusion, varying by material type.
Bed Temperature
The temperature of the heated build plate, used to improve first layer adhesion and prevent warping.
Cooling
The rate at which printed layers are cooled by part cooling fans, affecting surface quality and layer adhesion.
Bridging
Printing material across a gap without supports beneath it, requiring specific speed and cooling settings.
Overhang
A part of the model that extends outward beyond the layer beneath it at an angle, potentially requiring supports.
Z-Offset
The distance adjustment between the nozzle and the build plate at the “zero” position, critical for first layer adhesion.
Elephant’s Foot
A defect where the first few layers of a print are squished and spread out wider than the rest of the model.
Pillowing
A defect where the top surface of a print has bumps or holes due to insufficient top layers or cooling.
Stringing
Thin strands of filament between separate parts of a print, caused by oozing during travel moves.
Warping
The deformation of a print due to material shrinkage as it cools, typically causing corners to lift from the bed.
Thermal Runaway
A safety hazard where a failure in the heating system causes uncontrolled temperature increases.
Print Quality Concepts
Resolution
Typically refers to the minimum feature size a printer can produce, affected by XY resolution (determined by stepper motors and mechanics) and Z resolution (layer height).
Surface Finish
The quality and appearance of the outer surfaces of a print, affected by layer height, printing speed, and material.
Dimensional Accuracy
How precisely the printed object matches the dimensions of the original 3D model.
Layer Adhesion
The strength of the bond between successive printed layers, critical for structural integrity.
Tolerances
The allowable variation in dimensions, important when printing parts that need to fit together.
First Layer Adhesion
How well the initial layer sticks to the build plate, critical for print success.
Ghosting/Ringing
A print defect showing faint echoes of features, caused by printer vibration or acceleration too high.
Layer Shifting
A defect where layers are offset from previous ones, typically caused by mechanical issues or stepper motor skipping.
Advanced Printing Concepts
Linear Advance/Pressure Advance
A firmware feature that compensates for pressure in the extruder to improve corner quality and overall extrusion accuracy.
Input Shaping
A technique that compensates for printer vibrations by modifying movement commands to cancel out resonance effects.
Klipper
An alternative 3D printer firmware that uses a Raspberry Pi to handle the computational load, allowing for more advanced features and faster printing.
Marlin
A popular open-source firmware for 3D printers that controls all printer functions.
ABL (Auto Bed Leveling)
A feature where the printer automatically maps the build surface and compensates for irregularities during printing.
Mesh Bed Leveling
A process where the printer probes multiple points across the bed to create a height map and compensate for an uneven surface.
PID Tuning
The process of optimizing the Proportional, Integral, Derivative control parameters for stable temperature control.
Direct Extrusion
A setup where the extruder motor directly pushes filament into the hot end without an intermediate tube.
Dual Extrusion
A printer configuration with two extruders, allowing printing with different materials or colors in the same object.
IDEX (Independent Dual Extrusion)
A system with two independently controlled print heads, allowing for modes like duplication and mirror printing.
Firmware
The software programmed into the printer’s control board that manages all printer functions.
E-Steps (Extruder Steps per mm)
The number of stepper motor steps required to extrude 1mm of filament, an important calibration setting.
Delta Printer
A printer design using three arms arranged in a triangle to position the print head, known for fast movement but complex calibration.
Cartesian Printer
A printer design using independent X, Y, and Z axes arranged at right angles, the most common configuration.
CoreXY
A printer design that uses two belts and motors working together to move the print head in the X and Y directions, reducing moving mass.
Calibration
The process of fine-tuning printer settings to achieve optimal performance and print quality.
Post-Processing Techniques
Sanding
Using abrasives to smooth the surface of printed parts, typically progressing through increasingly fine grits.
Priming
Applying a preparatory coating to a printed part before painting to improve paint adhesion.
Painting
Applying paint to finished prints for aesthetic purposes or functional requirements.
Vapor Smoothing
Exposing prints (typically ABS) to vaporized solvent (like acetone) to melt the surface and create a smooth finish.
Epoxy Coating
Applying epoxy resin to strengthen parts and create a glossy finish.
Heat Treatment
Exposing prints to heat to increase strength and layer adhesion or to anneal specific materials.
Support Removal
The process of detaching support structures from the completed print, either manually or using soluble supports.
Polishing
Using compounds and tools to create a high-gloss finish on printed parts.
Acetone Smoothing
A specific vapor smoothing technique using acetone to smooth ABS prints.
Annealing
Heating prints to just below their glass transition temperature and allowing slow cooling to improve mechanical properties.
Industrial 3D Printing Concepts
AM (Additive Manufacturing)
The industrial term for 3D printing processes that build objects by adding material layer by layer.
RP (Rapid Prototyping)
Using 3D printing to quickly create prototypes for testing and development.
Topology Optimization
Computational design method that optimizes material layout within a design space for given constraints.
Build Volume
The maximum size of object a printer can produce, defined by X, Y, and Z dimensions.
Sintering
The process of compacting and forming a solid mass of material by heat and/or pressure without melting it to the point of liquefaction.
Powder Bed Fusion
A category of 3D printing processes including SLS, DMLS, and SLM that use powdered material fused by heat source.
GD&T (Geometric Dimensioning and Tolerancing)
A system for defining and communicating engineering tolerances on 3D printed parts.
ISO/ASTM Standards
International standards governing various aspects of 3D printing, including terminology, test methods, and quality assurance.
RFP (Request For Production)
A document issued by companies to source 3D printing service providers for production runs.
Digital Inventory
Replacing physical inventory with digital 3D models that can be printed on demand.
Common Challenges & Terminology
Bed Adhesion
The ability of the first layer to stick properly to the build plate, affected by leveling, temperature, and surface preparation.
Overextrusion
When too much filament is extruded, resulting in excess material and dimensional inaccuracy.
Underextrusion
When too little filament is extruded, resulting in gaps, weak layers, or incomplete prints.
Clogged Nozzle
Blockage in the nozzle preventing proper filament flow, typically caused by contaminants or carbonized filament.
Delamination
The separation of layers in a print, usually due to poor layer adhesion or material properties.
Heat Creep
Heat traveling up from the hot end into the cold end of the extruder, potentially softening filament prematurely.
Hygroscopic
The tendency of some filaments to absorb moisture from the air, which can cause printing problems.
Filament Runout
When the printer exhausts its filament supply during a print. Some printers have sensors to detect this.
First Layer Problems
Issues with the initial layer, which is critical for print success as it forms the foundation.
Print Failure
The unsuccessful completion of a print job due to various possible issues.
Spaghetti
The tangled mess of extruded filament that results when a print detaches from the bed and the printer continues extruding.
Resources & Community Terms
Thingiverse
A popular website for sharing 3D model files, primarily for free download.
Printables
A growing 3D model repository by Prusa Research, featuring quality ratings and contests.
OctoPrint
A web interface for controlling 3D printers remotely, often run on a Raspberry Pi.
Cura
A popular free slicing software developed by Ultimaker.
PrusaSlicer
A fork of Slic3r developed by Prusa Research, known for its optimized profiles.
Simplify3D
A commercial slicing software with advanced features and controls.
CAD (Computer-Aided Design)
Software used to create 3D models for printing. Examples include Fusion 360, SolidWorks, and Blender.
Open Source
Software or hardware designs freely available for modification and redistribution, common in the 3D printing community.
Maker
A term for individuals who create, build, and modify technology, including 3D printing enthusiasts.
RepRap
The self-REPlicating RAPid prototyper project, aimed at creating 3D printers that can print parts for more 3D printers.
This glossary covers essential terminology for understanding and discussing 3D printing. As the technology continues to evolve, new terms will emerge. Staying active in 3D printing communities and keeping up with industry publications will help you remain current with the expanding vocabulary of this rapidly advancing field.