The most comprehensive 3D printing glossary on the web in 2026. More than 225 definitions covering technologies, the ISO/ASTM 52900 process classes, materials, hardware, software, print settings, calibration, troubleshooting, and community vocabulary that makers actually use. Jump to a letter, or use the search shortcut (Ctrl+F on Windows, Cmd+F on Mac) to find a specific term. Cross-references inside each entry link to related terms, so the glossary works as a connected reference rather than a flat list.
A
ABS (Acrylonitrile Butadiene Styrene)
An engineering thermoplastic filament common in FDM 3D printing. Strong, heat-resistant, and machinable, but it warps easily and produces fumes during printing, so an enclosure and good ventilation are recommended. The same plastic used in LEGO bricks.
ACF (Anti-Curling Film)
A modern release film used in resin 3D printers, an alternative to traditional FEP. Provides smoother peel-off between layers, reduces print failure rates on detailed models, and lasts longer in heavy use. Common on newer Anycubic and Elegoo resin printers.
ACE Pro (Anycubic Color Engine)
Anycubic’s multi-material handling system, introduced with the Kobra S1 in 2025. The base ACE Pro unit supports up to 4 filaments; chaining a second ACE Pro plus a hub expands to 8 colours. Anycubic’s direct response to Bambu’s AMS and Creality’s CFS, repositioning Anycubic from a resin-first brand to a serious FDM contender.
Acceleration
The rate at which the printer changes velocity, measured in mm/s squared. Higher acceleration means faster prints but more risk of ghosting and missed steps. Modern printers with input shaping can push acceleration much higher than older designs.
Adaptive layer height
A slicer feature that varies layer height across a single print based on geometry. Steep curves get thinner layers (better detail), flat areas get thicker layers (faster print). Supported by Cura, PrusaSlicer, OrcaSlicer, and Bambu Studio.
Additive manufacturing (AM)
The industrial term for 3D printing. Building an object by adding material layer by layer, the opposite of subtractive manufacturing. Often used interchangeably with “3D printing” in professional contexts.
AI failure detection
Computer-vision monitoring of an active 3D print, with a model trained to recognise common failure modes (spaghetti, layer shift, first-layer detachment, filament runout) and pause the print automatically. Bambu Lab’s X1 Carbon runs detection on a built-in NPU; lower-tier Bambu, Prusa, and most other printers use third-party services like Obico or OctoEverywhere over a webcam. By 2026 this is a baseline expectation on flagship consumer printers.
AI mesh repair
Automated repair of common 3D model defects (non-manifold edges, inverted normals, intersecting geometry, holes) using either rule-based algorithms or machine-learning models. Bambu Studio, PrusaSlicer, OrcaSlicer, and dedicated tools like Microsoft 3D Builder and Meshmixer all offer mesh repair on import. The “AI” framing is largely marketing; the actual repair operations are well-understood geometric heuristics that predate the AI boom.
ALM (Additive Layer Manufacturing)
A synonym for additive manufacturing, more commonly used in British and European industrial contexts. The term emphasises the layer-by-layer nature of the process. Functionally interchangeable with “AM” and “3D printing” in most industry usage.
All-metal hotend
A hotend built without an internal PTFE liner. Handles higher print temperatures than lined hotends, enabling materials like ABS, Nylon, and PEEK. Required for printing engineering filaments.
AMF (Additive Manufacturing File Format)
An open 3D model file format developed as a successor to STL, supporting colour, multi-material, and curved surfaces. Largely superseded by 3MF in practice; AMF is rarely encountered in 2026 workflows.
AMS (Automatic Material System)
Bambu Lab’s multi-material unit, supporting up to four filaments per AMS. Chainable across multiple AMS units for up to 16-24 colours depending on printer model. Combined with Bambu Studio for one-click multi-colour printing. The 2025 generation includes the AMS 2 Pro (refreshed core unit) and the AMS HT (high-temperature filament-drying variant for PPA, PPS, and PEEK). Bambu’s competitor to Prusa’s MMU, Anycubic’s ACE Pro, and Creality’s CFS.
AMS HT (Bambu)
A higher-temperature variant of the Bambu Lab AMS, launched in 2025. Adds active 85C filament drying with brushless feed motors, ceramic-hardened filament inlets, and RFID-driven dryness profiles for Bambu-branded filaments. Compatible with H2D out of the box and with X1/P1 (via OTA, April 2025) and A1/A1 mini (October 2025). Chains up to 24 colours across multiple AMS HT units. The first AMS designed around high-performance filaments like PPA-CF, PPS, and PEEK.
Anti-aliasing (resin)
A resin slicer feature that softens the edges of each cured layer image, reducing visible pixelation on curved surfaces. Trades a small amount of detail for a smoother surface finish. Common in Chitubox and Lychee Slicer.
ASA (Acrylonitrile Styrene Acrylate)
A weather-resistant engineering thermoplastic similar to ABS but with much better UV resistance. The go-to filament for outdoor parts that need to withstand sunlight without yellowing or becoming brittle. Print like ABS: enclosed, ventilated, with good first-layer adhesion.
Auto bed leveling (ABL)
A printer feature that automatically measures the height of the build plate at multiple points and compensates for any tilt or warp during printing. Common implementations: BLTouch, CR Touch, inductive probes, and contactless laser systems.
ASTM F42 (Committee)
The ASTM International technical committee that develops standards for additive manufacturing. Co-publishes the ISO/ASTM 52900 terminology standard with ISO/TC 261. Most formal AM definitions you see in industry papers trace back to F42 documents.
B
Babystepping (also: Live Z)
A printer feature that lets you adjust the nozzle height by tiny increments (0.025mm to 0.1mm) during the first layer of a print, fine-tuning the Z-offset for perfect first-layer adhesion. Most modern printers (Prusa, Bambu, Klipper-equipped) support live babystepping.
Bambu A1 / A1 mini
Bambu Lab’s entry-tier Cartesian (bed-slinger) printer line, launched late 2023 and updated through 2025. The A1 has a 256mm cube build volume; the A1 mini is a 180mm cube. Both support the AMS via the Lite variant for multi-colour. The A1 series brought Bambu’s polish (auto bed level, vibration calibration, camera monitoring) to sub-$500 price points, putting heavy competitive pressure on every other entry-level FDM printer in 2024-2026.
Bambu H2D
Bambu Lab’s flagship dual-nozzle CoreXY printer, launched March 2025 at $3,499 USD. Features dual hardened-steel nozzles, a 350x320x325mm dual-nozzle build volume, 600mm/s top speed, the DynaSense servo extruder, eddy-current nozzle calibration, and a vision-assisted encoder system claiming 50um motion accuracy. Available in a “Laser Full Combo” variant that adds laser engraving and cutting modules. The H2D is the first Bambu machine designed around true IDEX-style dual-nozzle workflows rather than AMS filament-swapping.
Bambu Studio
The official slicer for Bambu Lab printers. A fork of PrusaSlicer with native AMS multi-material support, polished defaults, and tight integration with Bambu’s cloud workflow. See our Best 3D Printer Slicers guide.
Bed leveling
The process of ensuring the build plate sits at a consistent distance from the nozzle across its full area. Critical for first-layer adhesion. Manual bed leveling involves turning corner screws; auto bed leveling uses a probe. See also mesh bed leveling and tramming.
Benchy (3D Benchy)
A standardised tugboat model designed as a quick test print to evaluate a printer’s calibration and quality. The benchmark torture-test for FDM machines worldwide; the print exposes stringing, ghosting, overhang quality, and dimensional accuracy in one ~45-minute print.
Binder Jetting (BJT)
One of the seven ISO/ASTM 52900 process classes (BJT). A 3D printing process where a liquid binder is selectively deposited onto a powder bed to glue particles together one layer at a time. Used for full-colour sandstone parts, metal parts, and large industrial components. Invented at MIT in 1989 (Sachs et al.).
Bio-printing
3D printing technology applied to biological materials such as living cells, hydrogels, and tissue scaffolds. Used in research for tissue engineering, organoid production, and eventual organ printing. Still primarily a research-stage application.
Bioink
The “ink” used in bio-printing: a hydrogel matrix loaded with living cells, growth factors, and biomaterials. Bioinks must protect the cells during printing, then crosslink into a stable 3D scaffold. Common formulations use alginate, gelatin methacrylate (GelMA), or decellularised extracellular matrix.
Blender
A free, open-source 3D creation suite primarily used for animation, VFX, and game art, but heavily adopted by the 3D printing community for organic and artistic models: miniatures, tabletop figurines, character busts, and sculpted props. Strictly a mesh-modelling and sculpting tool rather than a parametric CAD program.
BLTouch
A widely-used auto bed leveling probe with a deployable touch pin. Works with any build plate surface (metal, glass, PEI, magnetic). Common upgrade for older Creality Ender machines.
BOM (Bill of Materials)
A parts list attached to a model page on platforms like MakerWorld, listing the screws, electronics, filament colours, and other materials needed to build the design. The basis of MakerWorld’s creator commission system.
Bondtech
A Swedish manufacturer of high-quality dual-drive extruders. The Bondtech BMG is a popular upgrade for printers that originally shipped with single-drive extruders, improving grip on the filament and reducing slippage.
Bottom exposure
The extended exposure time used for the first few layers of a resin print. Bottom layers cure longer than subsequent layers to ensure strong adhesion to the build plate. Typically 30 to 60 seconds versus 2 to 4 seconds for normal layers.
Bowden tube
A PTFE tube that guides filament from the extruder to the hotend in printers where the extruder motor is mounted away from the printhead. Lighter printhead, faster movement, but trickier with flexible filaments. The opposite of direct drive.
Bridging
Printing a horizontal span between two existing supports without any underlying structure. The slicer slows the print and increases part cooling to help the bridge solidify before it sags. Long bridges may still need supports.
Brim
A thin, single-layer outline of material extended around the base of a print, attached to the first layer. Improves first-layer adhesion and helps prevent warping on materials like ABS. Easier to remove than a raft, smaller than a skirt.
Build envelope
The maximum physical volume in which a 3D printer can operate, including the build plate and the printhead’s reach. Often confused with build volume: build envelope is the machine’s capability; build volume is the usable space for the actual part after accounting for clearances and homing offsets.
Build plate
The surface on which a 3D print is built. Also called the print bed or build surface. Common materials include glass, PEI sheets, magnetic spring steel, G10/Garolite, and textured powder-coated metal. The first layer adheres here.
Build volume
The maximum dimensions (X by Y by Z, in millimetres) of an object a printer can produce. A common consumer FDM build volume is 220x220x250mm; large-format machines reach 350x350x500mm or more. Larger build volumes need more space, more material, and longer prints.
C
C3DP (Construction 3D Printing)
Large-scale additive manufacturing of buildings and infrastructure using concrete, mortar, earth-based materials, or polymers. C3DP printers range from gantry systems building entire houses in 24 hours to robotic-arm printers shaping architectural facades. Companies include ICON, Apis Cor, COBOD, and Mighty Buildings.
CAD (Computer-Aided Design)
Software for creating 3D models that can be exported as STL or STEP files for 3D printing. Common parametric CAD tools include Tinkercad, Fusion 360, OnShape, FreeCAD, SketchUp, and OpenSCAD. Mesh-modelling and sculpting tools like Blender and ZBrush are technically not CAD but cover the organic and artistic side of 3D modelling.
CAL (Computed Axial Lithography)
A volumetric printing technique that uses tomographic-style light projections rotated around a vial of resin to cure the entire object simultaneously. Developed at UC Berkeley and Lawrence Livermore. Prints in seconds rather than hours, with no layers and no need for supports. Research-stage as of 2026.
Calibration cube
A simple 20mm cube test print used to verify a printer’s dimensional accuracy on all three axes. After printing, measure each side; deviations indicate where to adjust e-steps or scaling factors. The fastest sanity check after a printer upgrade or move.
Carbon fiber filament (CF)
A base filament (usually PETG, Nylon, or ABS) reinforced with short chopped carbon fibres for added stiffness and dimensional stability. Often suffixed “-CF” (e.g., PETG-CF, ASA-CF). Abrasive: requires a hardened steel nozzle.
Cartesian (kinematics)
A 3D printer motion system where each axis (X, Y, Z) is driven by a separate dedicated motor moving along a single direction. Simple and easy to understand, but limited in acceleration compared to CoreXY. The Prusa i3 is the iconic Cartesian design.
Castable resin
A specialty resin formulated to burn out cleanly during the lost-wax investment casting process used in jewellery manufacturing. The 3D print becomes a master pattern that is enclosed in plaster; the resin then evaporates without leaving ash, allowing molten metal to fill the cavity.
Ceramic 3D printing
Additive manufacturing using ceramic materials: alumina, zirconia, silica, hydroxyapatite, or porcelain. Technologies include SLA with ceramic-loaded resin, binder jetting on ceramic powder, and paste extrusion. Used in dental restorations, aerospace components, and art. Requires post-print debinding and sintering.
CFS (Creality Fusion System / Color Fusion System)
Creality’s multi-material handling system, introduced with the K2 Plus in 2025. Supports up to 4 filaments per unit; chaining additional units brings the system to 16 colours. Creality’s direct response to AMS and ACE Pro. Pairs with Creality Print and OrcaSlicer for slicing.
Chitubox
The de facto standard slicer for resin 3D printing. Free, with a paid Pro tier that adds advanced hollowing and support tools. The slicer most consumer resin printers ship with as the recommended choice.
CLIP (Continuous Liquid Interface Production)
A proprietary resin 3D printing technology developed by Carbon. Uses an oxygen-permeable window to create a thin uncured “dead zone” between the window and the part, enabling continuous, very fast layer-less printing. Mostly industrial.
Coasting
A slicer setting that stops extruding shortly before the end of a wall segment, using the remaining pressure inside the hotend to finish the line. Reduces small blobs at the end of perimeters. An alternative or complement to retraction.
Combing
A slicer feature that keeps the nozzle inside already-printed regions during travel moves, avoiding crossing exposed surfaces. Reduces visible defects from oozing and stringing on the part’s outer surface.
CoreXY (kinematics)
A printer motion system where two stationary motors drive crossed belts to move the printhead in X and Y. The build plate only moves in Z. CoreXY allows much faster acceleration than traditional Cartesian designs. Bambu X1, Voron 2.4, and most modern fast printers use CoreXY.
CR Touch
Creality’s first-party auto bed leveling probe, similar in concept to BLTouch but factory-installed on Creality printers. Uses a metal touch pin that briefly extends and retracts during the probing cycle.
CT scanning (in 3D printing)
Industrial computed tomography scanning is the dominant non-destructive metrology method for 3D-printed parts. X-rays produce a layer-by-layer interior map, revealing porosity, inclusions, dimensional accuracy, and defects invisible from the outside. Standard in qualified aerospace and medical AM workflows.
Cura (UltiMaker Cura)
A widely-used free slicer with the largest user base and plugin ecosystem in 3D printing. Maintained by UltiMaker. Supports the broadest range of printers out of the box. See our Best 3D Printer Slicers guide.
D
DED (Directed Energy Deposition)
One of the seven ISO/ASTM 52900 process classes (DED). A metal 3D printing process where a nozzle deposits metal powder or wire onto a substrate while an energy source (laser, electron beam, or plasma arc) melts it on contact. Used for large industrial parts, repairs, and adding features to existing metal components. See also WAAM.
Delta (kinematics)
A printer motion system where three vertical towers each control one arm attached to a floating effector. The arms coordinate to position the printhead anywhere within a cylindrical build volume. Fast and lightweight; common in FLsun Delta printers and some industrial designs.
Dental resin
A category of medical-grade resins formulated for dental applications: clear aligners moulds, surgical guides, crowns, dentures. Specific dental resins are biocompatible and approved for intra-oral use. The dental industry is one of the largest consumers of additive manufacturing globally.
DfAM (Design for Additive Manufacturing)
The engineering discipline of designing parts specifically for 3D printing rather than adapting designs originally made for casting or machining. DfAM uses techniques like lattice structures and topology optimization to take advantage of additive manufacturing’s geometric freedom.
Direct drive (extrusion)
An extrusion system where the motor that pushes filament sits directly above (or attached to) the hotend. Better for flexible filaments like TPU than Bowden, since there’s no long tube for the filament to compress in. Adds weight to the printhead.
DLP (Digital Light Processing)
A resin 3D printing technology that uses a digital projector to flash a full layer image at once, curing the entire layer simultaneously. Faster than scanning SLA. Resolution depends on the projector pixel count.
DLS (Digital Light Synthesis)
Carbon’s proprietary CLIP-based resin printing process. Combines continuous light projection with oxygen-permeable membrane and heat-triggered programmable photopolymerisation. Produces isotropic, end-use parts at injection-moulding-like speeds. Powered the Adidas Futurecraft 4D midsoles (2017-2023), and continues to be used for dental aligners, Riddell helmet liners, and Specialized bike saddles.
DMD (Directed Metal Deposition)
A metal DED variant where metal powder is blown into a focused laser beam to build up parts on an existing substrate. Used for repair (turbine blades, dies), hybrid manufacturing (DMD + CNC), and large near-net-shape parts. Different from DMLS or SLM which fuse a powder bed.
DMLS (Direct Metal Laser Sintering)
A powder bed fusion process where a high-power laser fuses metal powder particles into a solid part, layer by layer. Used in aerospace, medical implants, and high-performance engineering. Industrial, expensive, but produces near-net-shape metal parts. Related to SLM.
E
EBM (Electron Beam Melting)
A powder bed fusion process for metals where an electron beam in a vacuum chamber melts and fuses metal powder. Similar to DMLS but produces parts with less residual stress. Used for titanium implants and aerospace components. The Arcam EBM product line (acquired by GE Additive in 2017) was wound down in 2024-2025; EBM is shrinking as a commercial offering.
Elephant’s foot
A first-layer defect where the bottom of a print bulges outward, slightly wider than the layers above. Caused by the bed being too hot or the nozzle too close. Fixes: lower bed temperature 5C, raise Z-offset 0.02-0.04mm, and enable Elephant Foot Compensation (PrusaSlicer/OrcaSlicer) or Initial Layer Horizontal Expansion (Cura) at -0.1 to -0.2mm.
Enclosure
A sealed enclosure around an FDM printer that traps heat, reduces draughts, and contains fumes. Required for warp-prone materials like ABS and ASA. Often combined with a HEPA filter and activated carbon filter for ventilation.
Endstop (limit switch)
A switch or sensor that detects when a printer axis has reached its maximum or minimum position. Used during the “homing” routine at the start of every print to find the origin point. Mechanical endstops use physical switches; optical and Hall-effect variants are also common.
E-step calibration
Tuning the printer’s stored value for how many motor steps push one millimetre of filament. Done by marking 120mm of filament, telling the printer to extrude 100mm, and measuring the remaining filament. Bad e-steps cause systematic under- or over-extrusion.
Exposure time
In resin 3D printing, the duration each layer is exposed to UV light to cure. Too short and the layer won’t fully cure; too long and the print loses detail. Typical values: 2 to 4 seconds for normal layers on a fast modern resin printer, longer for bottom exposure.
Extruder
The mechanism on an FDM printer that grips and feeds filament into the hotend. Consists of a motor driving a knurled wheel or geared system. Comes in two configurations: direct drive (motor on printhead) and Bowden (motor remote).
F
FDM (Fused Deposition Modeling)
The dominant 3D printing technology in consumer and hobbyist markets. A thermoplastic filament is heated by the hotend and extruded through a nozzle, depositing layers onto the build plate. Same technology as FFF. Invented by Scott Crump and patented by Stratasys in 1989.
FEP (Fluorinated Ethylene Propylene)
A thin, semi-transparent release film stretched across the bottom of a resin vat. UV light passes through it to cure resin above, and cured layers detach from it as the build plate lifts. Consumable: replaced every few hundred prints. ACF is a modern alternative.
FFF (Fused Filament Fabrication)
Functionally identical to FDM, but a separate name created by the RepRap project to avoid Stratasys’s FDM trademark. Most open-source and consumer printers technically use FFF; the names are interchangeable in casual use.
Filament
The thermoplastic raw material used in FDM printing. Sold on spools, in 1.75mm or 2.85mm diameters, in many material types and colours: PLA, PETG, ABS, TPU, Nylon, and many more.
Filament dryer
A heated, low-humidity box that dries wet filament spools before or during printing. Required for hygroscopic materials like Nylon, TPU, and PETG. See our Best Filament Dryers guide.
First layer
The bottom-most printed layer, adhered directly to the build plate. The single most important layer in any FDM print: poor first-layer adhesion is the leading cause of print failures. Worth tuning with bed leveling, Z-offset, and first-layer-specific slicer settings.
Flexible resin
A resin formulation that produces rubber-like, bendable cured parts. Used for gaskets, grips, prototypes that need to flex, and orthotics. Less common than rigid resins and usually requires longer exposure times.
Flow rate (extrusion multiplier)
A slicer setting that scales how much filament is extruded relative to the theoretical amount. 1.0 is neutral; 0.95 reduces extrusion by 5%; 1.05 increases by 5%. Tuned to compensate for measurement variations across filament brands.
Fluidd
A web-based control interface for Klipper-powered 3D printers. Provides print monitoring, file management, and macro control through a clean, responsive UI. The main alternative to Mainsail; both serve similar purposes.
4D printing
3D printing of objects designed to change shape over time in response to a stimulus: heat, water, light, or magnetic field. The fourth dimension is time. Uses shape-memory polymers, hydrogels, or composite filaments with engineered anisotropy. Research-stage applications include self-deploying medical stents and adaptive aerospace skins.
FreeCAD
A free, open-source parametric CAD program. Steeper learning curve than commercial tools, but no subscription cost and full control over your design files. Strong choice for parametric mechanical design without lock-in.
Fusion 360
Autodesk’s flagship cloud-based CAD program. Free for personal/non-commercial use, subscription for commercial. Combines parametric modelling, freeform sculpting, simulation, and CAM in one package. The most-used CAD tool in the maker community.
G
G10 / Garolite
A composite material made of fiberglass and epoxy used as a build plate surface. Especially popular for printing Nylon, which adheres well to G10 without glue. Less common than PEI in 2026 but still preferred for specific materials.
G-code
The instruction language that 3D printers (and CNC machines) follow. Each line tells the printer to move to a position, extrude a specific amount of material, change temperature, or perform some other action. G-code is produced by a slicer from a 3D model.
Gantry
The bridging frame on a 3D printer that carries the printhead and moves it across the X and Y axes. Rigid gantries reduce ghosting and allow higher print speeds.
Generative design
A CAD technique where you specify the engineering constraints (loads, fixed points, materials, manufacturing process) and let the software produce optimised geometries that satisfy them. Often produces organic-looking shapes that would be impossible to manufacture without 3D printing. Found in Fusion 360, Siemens NX, and other industrial CAD packages.
Glass-fiber filament (GF)
A filament reinforced with chopped glass fibers (typically 10 to 20 percent by weight). Stiffer and stronger than the base polymer but less rigid than carbon fiber filament. Common in PETG-GF, PA-GF, and PP-GF. Abrasive: a hardened steel nozzle is required.
Ghosting (also: ringing)
Faint, repeating “echoes” of geometry on the surface of a print, visible just past sharp corners or holes. Caused by mechanical vibrations the printer can’t damp quickly enough at high speeds. Fixes: enable input shaping (eliminates most ghosting), reduce acceleration to 1000-3000mm/s squared, stiffen the frame, and use linear rails in place of V-wheel carriages.
GT2 belt
A toothed timing belt with 2mm tooth pitch, used on almost every consumer 3D printer to drive the X and Y axes. Steel-reinforced GT2 belts are the upgrade path for printers experiencing belt stretch under high acceleration.
Gyroid (infill pattern)
A geometric infill pattern that creates an interlocking, triply-periodic minimal surface. Strong in all directions, prints relatively quickly, and uses material efficiently. The default infill pattern recommended by most slicers in 2026.
H
Hardened steel nozzle
A nozzle made from hardened tool steel, designed to resist wear from abrasive filaments like carbon fiber, glass-filled materials, and metal-filled filaments. Mandatory if printing abrasive materials; brass nozzles wear out in hours.
Heated bed
A build plate with embedded heating elements. Keeps the first layer warm during printing, improving adhesion and reducing warping. Required for ABS, ASA, PETG, and most engineering filaments.
Hemera (E3D)
A direct-drive extruder from E3D combining a planetary gearbox with a built-in hotend. Compact, reliable, and a popular upgrade for printers seeking better flexible-filament handling.
HEPA filter
A High-Efficiency Particulate Air filter that captures 99.97% of particles 0.3 microns and larger. Used in printer enclosures to filter ultrafine particles emitted during printing. Pairs with activated carbon filters to also reduce VOC fumes (especially important for ABS and resin printing).
HIPS (High-Impact Polystyrene)
A filament often used as a soluble support material for ABS prints. HIPS dissolves in limonene (a citrus-derived solvent), leaving clean ABS parts behind. Also usable as a primary print material, though less common than ABS or ASA.
Hollowing
In resin printing, creating an internal cavity in a part to save resin and reduce print time. Hollowed parts need drainage holes so uncured resin can escape during printing and post-processing. Common slicers (Chitubox, Lychee Slicer) automate this.
HIP (Hot Isostatic Pressing)
A post-processing step for metal 3D-printed parts. The part is heated under high gas pressure (typically 100 to 200 MPa, 1000 to 1200C) to close internal porosity and improve fatigue properties. Standard practice for qualified aerospace and medical DMLS and SLM parts.
Hotend
The heated assembly on an FDM printer that melts filament and extrudes it through the nozzle. Includes a heater block, thermistor, heat sink, and nozzle. Operates at 180 to 260C for common filaments, up to 350C+ for engineering materials with an all-metal hotend.
Hygroscopic
A material that absorbs moisture from the air. Most 3D printing filaments are hygroscopic to some degree (especially Nylon, PETG, TPU); wet filament produces brittle prints with poor surface quality. Combat with a filament dryer.
I
IdeaMaker
Raise3D’s official slicer. Free, with strong support for Raise3D printers and a structured workflow oriented toward small-batch production. Less popular than PrusaSlicer or OrcaSlicer in the consumer market.
IDEX (Independent Dual Extruder)
A dual-extrusion design where the two printheads move independently along the X axis rather than sharing a single carriage. Enables mirror printing (two identical copies at once), duplicate printing, and zero cross-contamination between materials. Common on Sovol SV04, Snapmaker J1, and BCN3D Epsilon.
Inductive probe (also: Capacitive probe)
Bed-leveling probes that detect proximity to the metal build plate without touching it. Inductive probes work only on metal beds; capacitive probes work on any surface but are less precise. Both are alternatives to physical-touch probes like BLTouch.
Infill
The internal structure of an FDM print, hidden behind the outer walls and top/bottom layers. Specified as a percentage (typically 10 to 30 percent for non-structural parts) and a pattern (gyroid, cubic, honeycomb, etc.). Higher infill means stronger but heavier and slower prints.
Input shaping
A motion-control technique that cancels vibration-induced ringing by feeding the planner anticipatory commands. Pioneered as control theory in the late 1980s (Singer and Seering, MIT) and popularised in 3D printing by Klipper. Now standard in Marlin 2.1+ and Bambu firmware, with the Bambu H2D adding live vision-based active compensation in 2025. The single biggest reason 600mm/s prints became routine in 2024-2026.
IPA (Isopropyl Alcohol)
The standard solvent for cleaning uncured resin off freshly-printed resin parts. Typically used at 90 to 99 percent concentration. Resin parts soak in IPA for 3 to 10 minutes before wash and cure drying. Skin contact should be avoided; use gloves.
Ironing
A slicer feature that runs the heated nozzle back over the top surface of a print after the last layer is laid down, smoothing it. Produces a near-mirror finish on flat top surfaces at the cost of extra print time.
ISO/ASTM 52900 (Terminology Standard)
The international standard that defines additive manufacturing terminology. Co-developed by ISO/TC 261 and ASTM F42. Defines the seven process classes recognised across industry: binder jetting, directed energy deposition, material extrusion, material jetting, powder bed fusion, sheet lamination, and vat photopolymerization.
Isotropic vs anisotropic
Isotropic parts have the same mechanical properties in every direction. Anisotropic parts are weaker along certain axes; FDM prints are notably anisotropic, with weak layer adhesion along the Z-axis. Print orientation matters for functional parts.
J
Jerk (also: Junction deviation)
The instantaneous velocity change a printer allows at the start of a move or at corners. Higher jerk produces faster prints with sharper corners but more vibration; lower jerk is smoother but slower. Modern Marlin and Klipper firmware use “Junction Deviation” as a more refined replacement for raw jerk values.
K
Klipper
A community firmware that runs on a Raspberry Pi alongside the printer’s main board, enabling faster prints, advanced motion features (input shaping, pressure advance), and remote management. Common on Voron printers and the Creality K-series. Pairs with web interfaces like Mainsail or Fluidd.
L
Lattice structure
A geometric pattern of repeating cells (e.g., gyroid, honeycomb, octet truss) used inside parts to reduce weight while preserving strength. A signature application of DfAM: impossible to manufacture with traditional methods, easy with 3D printing.
Layer adhesion
How firmly each printed layer bonds to the one below. Weak layer adhesion makes prints snap along horizontal lines. Fixes: raise hotend temperature 5-10C, increase wall and infill density, reduce part-cooling fan in the first few layers, use a hotter material (PETG/ABS over PLA for stressed parts), and ensure filament is dry (hygroscopic materials lose adhesion when wet).
Layer height
The vertical thickness of each printed layer. Smaller values produce smoother, more detailed prints but take longer; larger values are faster but show visible layer lines. Common FDM values: 0.1mm (fine), 0.2mm (standard), 0.3mm (draft). Resin printers use 0.025 to 0.1mm.
Layer line
The visible horizontal line on an FDM print’s surface where one layer meets the next. Less visible with smaller layer heights. Layer lines on curves produce “stair-stepping,” a sloped surface artifact unique to layered printing.
Layer shift
A print defect where one or more layers suddenly offset horizontally from the layers below. Caused by missed stepper motor steps, belt slip, physical obstruction, or thermal throttling. Fixes: retension belts (firm but not over-tight), reduce acceleration to 1500-3000mm/s squared, check pulley grub screws, increase stepper motor current incrementally, and clear any obstructions in the gantry path.
LCD (resin printing)
In resin 3D printing, the masked LCD screen that selectively blocks or transmits UV light to cure a layer’s pattern. Modern consumer resin printers use 8K, 12K, 14K, or 16K LCDs for high detail (the Anycubic Photon Mono M7 Pro and Elegoo Saturn 4 Ultra 16K shipped 16K screens in 2024-2025). The LCD is consumable, with a typical lifespan of 1,000 to 2,000 print hours.
Lead screw
A threaded rod used to drive the Z-axis up and down on most FDM printers. Each rotation moves the gantry or bed by one thread pitch (usually 8mm). Smooth lead screws produce consistent layer heights; bent or worn screws cause Z-banding.
LiDAR (in 3D printing)
Micro-LiDAR sensors mounted near the printhead are used in 3D printers (most notably the Bambu H2D and X1 Carbon) for first-layer inspection, flow-rate calibration, automated nozzle-height probing, and active extrusion compensation. Distinct from automotive or geospatial LiDAR: the sensor measures distance to the build plate or to a printed layer with micrometre precision. Pioneered in the consumer space by Bambu in 2022 and increasingly copied across the industry.
Linear rail
A precision motion-guide rail with ball-bearing carriages, used on premium 3D printers in place of v-wheel or LM8UU rod systems. Linear rails reduce backlash and play, enabling cleaner prints at high speeds. Standard on Voron, Bambu X1/X1C, and other top-tier machines.
LOM (Laminated Object Manufacturing)
An early sheet lamination 3D printing process where layers of adhesive-coated paper, plastic, or metal foil are bonded together and cut to shape with a laser or knife. Invented by Helisys in the late 1980s. Largely obsolete in 2026 but historically significant as one of the first commercial 3D printing technologies.
LPBF (Laser Powder Bed Fusion)
The ISO/ASTM term for laser-based metal powder bed fusion, encompassing both DMLS and SLM under one umbrella. The most common industrial metal 3D printing technology. Standard for aerospace, medical implants, and tooling.
M
Mainboard
The printer’s main controller board. Receives G-code commands and drives the motors, heaters, fans, sensors, and other components. Common platforms in 2026: BTT Octopus (open-source), Bambu’s proprietary controllers, Prusa’s xBuddy, Creality’s silent boards.
Mainsail
A web-based control interface for Klipper-powered 3D printers. Feature-rich and customisable. The main alternative to Fluidd; users typically pick whichever feels cleaner to them.
Manifold geometry
A 3D model with a watertight, properly-connected surface that defines a single solid volume. Non-manifold geometry (broken surfaces, geometry intersecting itself, edges shared by more than two faces) often fails to slice cleanly. Most modern slicers auto-repair minor non-manifold issues.
Marlin
The most widely-used open-source firmware for FDM 3D printers. Runs on the printer’s mainboard directly. Mature, well-supported, and the foundation for many custom printer projects. Klipper is the modern alternative for advanced users.
Material extrusion (MEX)
One of the seven ISO/ASTM 52900 process classes. Material is dispensed through a heated nozzle and deposited layer by layer onto a build platform. Encompasses FDM, FFF, and large-format pellet extrusion. The dominant consumer 3D printing class.
Material Jetting (MJT)
One of the seven ISO/ASTM 52900 process classes (MJT). A 3D printing process where liquid photopolymer is deposited in droplets through inkjet-style nozzles, then cured with UV light layer by layer. Produces very high resolution, smooth surfaces, and the ability to mix materials within a single part.
Matte filament
A PLA variant formulated to produce a non-reflective, matte surface finish that hides layer lines better than standard PLA. Popular for display models and prints where surface aesthetics matter. Slightly more brittle than glossy PLA.
Mesh
The triangulated surface representation of a 3D model. STL files store meshes. Higher-poly meshes contain more triangles and produce smoother curves but result in larger files. The mesh defines the outer shell that the slicer fills.
Mesh bed leveling
An auto bed leveling implementation that probes a grid of points across the build plate and creates a topographic map (mesh) of the surface. During printing, the printer adjusts Z-height in real time to follow the mesh, compensating for any tilt or warp without manual adjustment.
Mesh repair
Automated correction of common 3D model defects: non-manifold edges, flipped normals, intersecting faces, internal holes, and shells with inverted winding. Modern slicers (Bambu Studio, PrusaSlicer, OrcaSlicer, Cura) run mesh repair on import. Standalone tools include Microsoft 3D Builder, Meshmixer (now legacy), Netfabb, and Blender’s 3D Print Toolbox. Critical step when downloading STL files from model repositories where geometry quality is uneven.
Metrology
The science of measurement. In 3D printing, metrology covers dimensional inspection (CT scanning, coordinate measuring machines, structured light scanners), surface roughness measurement, and material characterisation. Essential for any qualified production AM workflow and increasingly important as printers move into regulated industries.
MJF (Multi Jet Fusion)
HP’s proprietary powder bed fusion process. Inkjets deposit a binding agent and detailing agent onto a powder bed; thermal energy then fuses the powder. Used for production-grade nylon parts.
MMU (Multi-Material Unit)
Prusa Research’s multi-material upgrade for MK3, MK4, and Core One printers. MMU3 is the current version, supporting up to 5 filaments. Prusa’s competitor to Bambu’s AMS.
MSLA (Masked SLA / LCD 3D printing)
A resin 3D printing technology that uses an LCD screen as a dynamic mask in front of a UV light source. The technology behind every consumer resin printer in 2026 (Anycubic, Elegoo, Phrozen, Creality). Sometimes also called LCD printing.
Multi-color printing
FDM printing using more than one colour of filament in a single print. Achieved with a multi-material system (AMS, MMU) or a toolchanger. Generates a wipe tower to purge old colour between transitions.
N
Near-net shape
A part produced close to its final geometry, requiring only minor machining or finishing. 3D printing’s natural output is near-net shape: a 3D-printed metal bracket may need only critical surfaces machined to tolerance, versus a billet that requires extensive subtractive work. A key economic argument for AM in production.
nFEP (Non-stick FEP)
A treated variant of FEP resin release film with reduced surface adhesion. Cured resin layers detach from nFEP with less force, reducing print failures on tall or detailed prints. ACF is an alternative with similar benefits.
Nozzle
The final component of the hotend, where melted filament is extruded onto the print. Standard diameter is 0.4mm; smaller (0.2mm) for fine detail, larger (0.6mm, 0.8mm, 1.0mm) for faster prints. Hardened steel required for abrasive filaments; ruby for the longest life.
NPJ (NanoParticle Jetting)
A proprietary XJet metal and ceramic 3D printing process. Liquid suspensions of metal or ceramic nanoparticles are jetted onto a build tray and heated; the carrier evaporates and the nanoparticles sinter together. Produces fine-feature, high-density parts without a powder bed. Niche industrial use; XJet wound down its NPJ commercial operations in 2024 and the technology is largely dormant in 2026.
Nylon (Polyamide / PA)
An engineering filament known for toughness, flexibility, and abrasion resistance. Common in functional parts, gears, and hinges. Highly hygroscopic: must be dried before printing and stored in a dry box.
O
Obico (formerly Spaghetti Detective)
An AI-powered print monitoring service that watches your printer through a webcam and pauses the print if it detects spaghetti failures or other anomalies. Integrates with OctoPrint and Klipper. Free tier with paid premium options. By 2026 it competes with OctoEverywhere’s free Bambu-targeted AI failure detection and with Bambu’s built-in NPU-based detection on the X1 Carbon and H2D.
OBJ
A 3D model file format similar to STL but supporting colour and texture information. Less common than STL in 3D printing workflows, more common in 3D rendering and gaming.
OctoPrint
An open-source print server that runs on a Raspberry Pi connected to your 3D printer. Provides a web interface for uploading G-code, monitoring prints with a webcam, and remotely controlling the printer. Predecessor to Klipper’s Mainsail/Fluidd interfaces.
OnShape
A cloud-based parametric CAD program with strong assembly and collaboration features. Free for non-commercial use (public documents). Particularly popular in education and remote engineering teams. Browser-based, no installation needed.
OpenSCAD
A free, open-source 3D modelling tool that uses a programming language rather than a graphical interface. Designs are described in code; the rendered model is generated from that code. Popular for parametric mechanical parts and customisable designs.
OrcaSlicer
A community fork of Bambu Studio, broadened to support many more printer brands (Voron, Klipper, Prusa, Creality, Anycubic, Elegoo). No cloud-account dependency. The most active slicer project in 2026, with excellent calibration tools.
Overhang
Any part of a print that extends outward without underlying material to support it. Overhangs steeper than ~45 degrees from vertical generally need supports to prevent drooping. Modern slicers can also use bridging tricks for short overhangs.
Over-extrusion
A condition where the printer pushes out more filament than the model needs at a given speed. Produces blobs, rough surfaces, and dimensional inaccuracy. Fix by calibrating flow rate downward (typical 0.92-1.00 multiplier) and verifying e-steps. Use a calibration cube to dial in real-world dimensional accuracy.
P
P3 (Programmable PhotoPolymerization)
Stratasys’ proprietary resin 3D printing technology used in their Origin series. Combines voxel-level light projection with pneumatic membrane separation to print engineering and dental resins at production speeds. Competes with Carbon DLS in the production resin market.
PA (Polyamide)
The technical name for Nylon. PA12 (Nylon 12) and PA6 (Nylon 6) are the two most common variants in 3D printing. Industrial SLS and MJF workflows almost always reference parts as “PA” rather than “Nylon”. See also Nylon for printing characteristics.
PC (Polycarbonate)
An engineering filament with very high toughness, impact resistance, and temperature resistance. Prints around 280C and requires an enclosure. Used for safety equipment, functional engineering parts, and bullet-proof transparent applications.
PEEK (Polyether Ether Ketone)
A high-performance engineering polymer with exceptional temperature resistance, chemical resistance, and strength. Used in aerospace, medical implants, and oil-and-gas applications. Prints at approximately 360 to 410C with a heated chamber at 120-180C, and demands specialised equipment.
PEI (Polyetherimide / Ultem)
A high-performance engineering polymer in the same family as PEEK, with slightly lower temperature resistance but excellent strength-to-weight ratio. Ultem is SABIC’s trademark name for polyetherimide (originally GE Plastics, sold to SABIC in 2007). Also: PEI sheets are widely used as a build plate surface for FDM printers.
Pellet extruder
An extruder that uses plastic pellets (the same feedstock used in injection moulding) instead of filament spools. Pellets are much cheaper per kilogram than filament. Used in large-format and industrial 3D printers; rare in consumer setups.
PETG
A modified version of PET (the plastic used in water bottles), engineered for 3D printing. Stronger than PLA, more chemical-resistant, and prints without the warping issues of ABS. A good general-purpose engineering filament. Mildly hygroscopic. Carbon-fiber variant (PETG-CF) is widely used.
PLA (Polylactic Acid)
The most common and beginner-friendly 3D printing filament. Made from renewable resources (corn starch, sugarcane), prints at low temperatures (190 to 220C), has minimal odour, and produces dimensionally-stable parts. Standard PLA deforms above ~60C, but annealed and high-temp variants (HT-PLA, PLA+ blends) hold their shape past 100C. The default starting material for any FDM owner.
Polypropylene (PP)
A tough, chemically-resistant filament that resists fatigue from repeated bending (living hinges). Difficult to print because nothing adheres well to PP: most printers need specialised PP-tape or specific PP-compatible build plates.
Powder Bed Fusion (PBF)
One of the seven ISO/ASTM 52900 process classes (PBF). An umbrella category of 3D printing technologies where particles in a powder bed are fused together selectively, layer by layer, by a heat source. Includes SLS, MJF, DMLS, SLM, and EBM.
Power supply (PSU)
The unit that converts wall AC voltage to the DC voltage the printer’s electronics and heaters need. Consumer printers use 24V supplies rated 350W to 600W. PSU quality matters for reliability: Mean Well and Delta are the trusted brands in the maker scene.
PPA (Polyphthalamide)
A semi-aromatic nylon variant with higher temperature resistance, strength, and chemical resistance than standard PA12. Prints around 290-310C and needs aggressive drying (5+ hours at 95C). Common as a carbon-fibre composite (PPA-CF) for DfAM parts that approach injection-moulded performance. Made practical on consumer hardware by the AMS HT class of high-temperature filament dryers in 2025.
PPS (Polyphenylene Sulfide)
A high-performance engineering thermoplastic with continuous-use temperature near 200C, excellent chemical resistance, and inherent flame retardancy. Prints around 320-340C and requires sustained drying above 100C, historically out of reach for desktop machines. The 2025 generation of high-temperature filament dryers and the AMS HT brought PPS within reach of advanced hobbyists running enclosed all-metal printers.
Pressure advance (Linear advance)
A Klipper firmware feature (called Linear Advance in Marlin) that compensates for the spring-like behaviour of melted filament inside the hotend. Improves corner sharpness and consistent extrusion at higher speeds.
Print farm
A workshop or facility running multiple 3D printers in parallel for production-scale output. Print farms range from a few hobbyist machines selling on Etsy to industrial setups with hundreds of printers. Slicers like OrcaSlicer and platforms like Creality Cloud support cluster printing.
PrusaSlicer
The official slicer for Prusa Research printers and the codebase from which Bambu Studio and OrcaSlicer are forked. Free, open-source, and quarterly-updated.
PTFE (Polytetrafluoroethylene / Teflon)
A low-friction polymer used in 3D printers for the Bowden tube and as a liner in some hotends. PTFE breaks down and releases toxic fumes above ~260C, which is why printers needing higher temperatures use all-metal hotends.
PVA (Polyvinyl Alcohol)
A water-soluble support filament used in dual-extrusion printers. PVA prints alongside the main material, then dissolves in water when the print finishes, leaving clean overhangs and internal cavities. Expensive and very hygroscopic.
R
Raft
A thick first-layer base printed below the actual part, used for printers with poor bed adhesion or for prints with very small bottom contact areas. The part attaches to the raft, which is removed after printing. Largely superseded by brims on modern printers.
Rapid prototyping
The original commercial use case for 3D printing: creating prototypes of physical products quickly and cheaply, without the lead time of traditional manufacturing. Late-1970s and 1980s engineering teams adopted 3D printing primarily for this purpose. Now expanded to include rapid manufacturing of end-use parts.
Recycled filament
Filament produced from post-consumer or post-industrial plastic waste. Quality varies: rPETG and rPLA from major brands print as well as virgin material; cheaper recycled filament can be inconsistent. A small but growing share of the sustainability-conscious maker market in 2026.
RepRap
The open-source 3D printer movement founded by Adrian Bowyer in 2005. RepRap printers were designed to be self-replicating: each could print many of the plastic parts needed to build another (motors, electronics, and metal rods still had to be sourced). RepRap is the historical root of nearly every consumer FDM printer in production today.
Resin (photopolymer)
A liquid UV-curable polymer used in SLA, DLP, and MSLA printing. Comes in dozens of formulations: standard, tough, flexible, castable, dental, engineering, water-washable. Cured resin is rigid plastic; uncured resin is toxic and requires gloves and ventilation.
S
Salmon skin (resin defect)
A surface artifact on resin prints where curved areas show a faint diagonal pattern reminiscent of fish scales. Caused by the pixel grid of the LCD screen interacting with sloped geometry. Reduced by anti-aliasing and higher-resolution screens.
SCARA (kinematics)
A printer motion system using two rotating arms (like a robot arm) to position the printhead. Compact footprint with potentially large reach, but less common than Cartesian or CoreXY in consumer printers.
Service bureau
A company that prints 3D models on behalf of customers. Customers upload a model file, choose a material and finish, and receive the printed part by mail. Common providers: Shapeways, Sculpteo, Hubs, Xometry, Craftcloud.
Sheet lamination (SHL)
One of the seven ISO/ASTM 52900 process classes. Sheets of material are stacked, bonded, and cut to shape layer by layer. Includes LOM (paper or plastic sheets) and Ultrasonic Additive Manufacturing (metal foils bonded by ultrasonic welding). The smallest of the seven classes in commercial use today.
Silk filament
A PLA variant containing additives that produce a high-gloss, silky surface finish that hides layer lines and shimmers as the angle changes. Popular for decorative prints. Slightly weaker than standard PLA.
SketchUp
A 3D modelling tool with a focus on architectural and product design. Originally famous for ease of use, now offered in free web and paid pro tiers. Less precise than parametric CAD but accessible for users coming from a drawing background.
Skirt
A few single-layer outlines printed around (but not touching) the actual part. Primes the extruder and gives a chance to verify the build plate is level before the real print starts. Smaller and less helpful for adhesion than a brim or raft.
SLA (Stereolithography)
The original 3D printing technology, demonstrated by Chuck Hull in 1983 and patented in 1986. A UV laser traces each layer’s pattern on the surface of a vat of liquid resin, curing it solid. Slower than MSLA but historically the highest-resolution method.
Slicer
The software that turns a 3D model into the layer-by-layer instructions (G-code) your printer follows. Common FDM slicers: Bambu Studio, OrcaSlicer, PrusaSlicer, Cura, SuperSlicer, IdeaMaker. Resin slicers: Chitubox, Lychee Slicer.
Slicing
The process of converting a 3D model into printer-ready G-code, done by a slicer. The slicer mathematically cuts the model into horizontal layers, calculates the tool path for each, and writes the instructions the printer follows.
SLM (Selective Laser Melting)
A metal powder bed fusion process closely related to DMLS. Historically the distinction was that SLM fully melted the metal powder while DMLS only sintered it, but modern DMLS systems fully melt the powder as well. The two terms are used interchangeably in practice today, and both fall under the ISO/ASTM umbrella of LPBF.
SLS (Selective Laser Sintering)
A powder bed fusion process where a laser fuses thermoplastic powder (commonly nylon) into solid parts, layer by layer. The unused surrounding powder supports the part, eliminating the need for printed supports.
Spaghetti (failed print)
A catastrophic FDM print failure where the printer continues laying down filament after the part has detached from the build plate. The filament piles up as messy strings of plastic. Modern printers with camera-based failure detection (Bambu, Obico) often catch this and pause the print.
STEP
A CAD file format used in engineering. Unlike STL, STEP files store the original parametric geometry, allowing the model to be edited in CAD software. Common in industry. Supported as input by PrusaSlicer, Bambu Studio, and OrcaSlicer in modern versions.
Stepper motor
A motor that rotates in discrete, precise increments (steps) rather than continuously. Used throughout 3D printers for the X, Y, Z, and extruder axes because their precision is what enables accurate part dimensions. Driven by TMC drivers on the mainboard.
STL
The most common 3D model file format for 3D printing. Stores a model as a triangulated mesh. Universal slicer support. Does not embed colour, materials, or print settings (those go in 3MF).
Stringing
Fine, hair-like strands of filament left between separate parts of a print where the nozzle travels. Usually caused by oozing during travel moves. Fixed by tuning retraction (typical: 4-8mm distance, 25-45mm/s speed for Bowden; 0.4-2mm at 25-45mm/s for direct drive), lowering print temperature 5-10C, and enabling Z-hop or combing in the slicer.
Subtractive manufacturing
Manufacturing by removing material from a larger block, the opposite of additive manufacturing. Examples: CNC milling, lathe turning, drilling. Produces high precision but wastes material as chips and swarf.
SuperSlicer
A community fork of PrusaSlicer with extra advanced features, calibration assistants, and ironing controls. Less actively developed than OrcaSlicer in 2026 but still preferred by power users with specific tuning needs.
Supports
Temporary printed scaffolding that holds up overhangs and bridges during a print. Removed after printing. Two main families: traditional grid or line supports (cheap to print, harder to remove) and tree supports (less material, easier to remove). Slicer settings control where supports go.
T
3D model
A digital representation of a three-dimensional object, typically stored as a mesh (STL, OBJ) or parametric geometry (STEP). The input to a slicer. Created in CAD software or downloaded from model repositories.
3D printing
The process of building three-dimensional objects from a digital file by adding material one layer at a time. Same as additive manufacturing. Encompasses many technologies, from desktop FDM to industrial metal DMLS.
3MF
A modern container file format that embeds print settings, multi-material data, and metadata alongside the model geometry. Smaller and more efficient than STL, increasingly the preferred format on platforms like MakerWorld and Printables.
Temperature tower
A calibration test print designed to find the optimal print temperature for a specific filament. The tower prints sections at progressively decreasing temperatures (e.g., 220C at the bottom, 190C at the top). The user then inspects which section printed best.
Tinkercad
A free, browser-based CAD tool aimed at beginners and students. Designs are built by combining simple geometric primitives. The default starting point for first-time 3D modellers and for K-12 classrooms.
TMC driver (Trinamic)
A family of advanced stepper-motor drivers (TMC2208, TMC2209, TMC5160) made by Trinamic. Quieter than older A4988 drivers and support sensorless homing and stallguard. Standard on most 2026 printers, eliminating audible stepper whine.
Toolchanger
A multi-extruder system that physically swaps between separate printheads during a print, rather than using a single multi-feed extruder. Allows independent calibration per material and zero cross-contamination. Examples: Prusa XL, E3D Toolchanger, Bambu H2D.
Top and bottom layers
The solid upper and lower skins of a 3D print, sitting above and below the infill. Typically 3 to 5 layers each. Too few and the infill shows through the surface; too many and the print takes longer.
Topology optimization
A computational technique that removes material from a part in areas of low stress while preserving structural integrity in high-stress areas. Produces organic, weight-optimised shapes. A core tool of DfAM.
Tough resin
A resin formulation engineered to be more impact-resistant than standard resin, with mechanical properties closer to ABS. Used for functional parts, prototypes that need to flex slightly, and snap-fit assemblies. Also called “ABS-like” resin.
TPE (Thermoplastic Elastomer)
The parent class of flexible 3D printing filaments. TPU is the most common TPE variant; others include TPC and TPV. All share rubber-like flexibility, abrasion resistance, and chemical resistance. Best printed with direct drive extruders and slow speeds.
TPU (Thermoplastic Polyurethane)
A flexible filament, available in several Shore hardness ratings (85A is soft, 95A is firmer). Used for phone cases, gaskets, shoe soles, and any flexible part. Easier to print with direct drive extruders than Bowden.
Tramming
Aligning the build plate perpendicular to the printhead’s motion. Different from bed leveling: leveling compensates for variations in the build plate’s surface; tramming corrects the gantry and Z-axis being out of square with the bed.
Tree supports (also: Organic supports)
Branched, automatically-generated support structures that touch the print only at the tips of slender branches. Cura introduced the original Tree Supports algorithm; Prusa’s refined Organic Supports (later adopted by Bambu and Orca) is the modern standard.
U
Under-extrusion
A condition where the printer extrudes less filament than the model needs, producing gaps in walls, weak layer adhesion, and porous surfaces. Causes and fixes, in order: dry the filament (hygroscopic), check for partial nozzle clog, raise temperature 5-10C, calibrate flow rate (typical 0.95-1.02 multiplier), increase e-step calibration, and inspect the extruder gear for wear.
V
VAM (Volumetric Additive Manufacturing)
The umbrella term for 3D printing processes that form an entire object simultaneously rather than layer by layer. Includes CAL (tomographic light projection) and xolography. See also volumetric 3D printing. Primarily a research field as of 2026, with the first commercial systems just emerging.
Vase mode (spiralize)
A slicer mode that prints a single continuous outer wall in a spiral, with no infill, no top, and no layer transitions. Produces thin-walled hollow shapes (vases, lampshades) very quickly. Limited to objects that can be printed as a single continuous outline.
Vat (resin)
The container holding liquid resin on an MSLA, SLA, or DLP printer. The bottom of the vat is the release film (FEP, nFEP, or ACF); UV light passes through it to cure resin above. The build plate dips into the vat for each layer.
Volcano hotend
An E3D hotend design with a longer melt zone than a standard V6, enabling higher flow rates. Used with larger nozzles (0.6 to 1.2mm) for fast prints. The CHT (Core Heating Technology) nozzle from Bondtech further increases throughput in Volcano-style hotends.
Volumetric 3D printing
An emerging technology that forms entire 3D structures at once, without the layer-by-layer process used by all current commercial 3D printers. Primarily in the research phase as of 2026; not yet commercially viable for production.
Voron
An open-source DIY printer family built from kits or sourced parts. Models include the Voron 2.4, Voron Trident, and Voron 0. Known for being among the fastest, best-engineered consumer FDM printers when properly assembled. Almost always runs Klipper.
VPP (Vat Photopolymerization)
One of the seven ISO/ASTM 52900 process classes. Liquid photopolymer resin is selectively cured by UV light, layer by layer. Encompasses SLA (laser), DLP (projector), MSLA (LCD mask), and CLIP/DLS (continuous). The dominant high-detail consumer and prosumer resin printing class.
W
WAAM (Wire Arc Additive Manufacturing)
A metal 3D printing process that uses an electric arc to melt metal wire onto a substrate, building up large parts at high deposition rates. Used in aerospace, shipbuilding, and architectural metalwork. A specialised form of DED.
Walls (also: perimeters)
The outer printed surfaces of an FDM part that form its visible exterior. Typically 2 to 4 walls (each 0.4mm if using a standard nozzle). More walls mean stronger parts at the cost of print time. Distinct from infill (internal) and top/bottom layers (skins).
Warping
A print defect where the corners lift away from the build plate during printing, caused by thermal contraction. Common in ABS and ASA. Fixes (in priority order): a heated enclosure, heated bed at 95-110C for styrenics, a brim 5-10mm wide, slower first-layer speed (15-25mm/s), and PEI or garolite build surface.
Wash and cure
The standard post-processing workflow for resin prints. First wash: soak the part in IPA to remove uncured resin. Then cure: expose the cleaned part to UV light to fully harden it. Dedicated wash-and-cure stations combine both steps.
Water-washable resin
A resin formulation that can be cleaned with plain water instead of IPA. Convenient and safer for users without IPA storage, but the cured parts tend to be slightly more brittle than standard resin and the print quality is incrementally lower.
Wipe tower (also: purge tower)
A separate structure printed alongside a multi-material print where the extruder purges old filament when switching between materials or colours. Catches the colour-bleed transitions away from the actual part. Used by AMS, MMU, and other multi-material systems.
Wood-filled filament
A PLA blended with fine wood particles (often bamboo, birch, or pine). Prints look and feel like wood, can be sanded and stained, and have a wood-like aroma during printing. Slightly abrasive: a hardened steel nozzle extends nozzle life.
X
X, Y, and Z axes
The three orthogonal axes that define a 3D printer’s motion. By convention: X is left-right, Y is front-back (or vice versa depending on printer design), and Z is up-down (vertical). The slicer generates G-code with movements expressed as combinations of X, Y, and Z coordinates.
Z
Z-banding
A print defect where horizontal bands appear at regular intervals on a print’s surface, corresponding to the pitch of the Z-axis lead screw. Caused by a bent lead screw, misaligned couplers, or backlash. Fixes: replace the lead screw if visibly bent, install a flexible (oldham) coupling, add anti-backlash nuts, and verify the Z-axis steps-per-mm calibration. Distinct from Z-wobble.
Z-hop
A slicer setting that raises the nozzle slightly during travel moves to avoid catching on already-printed material. Reduces blob defects but adds time. Combined with retraction for stubborn stringing issues.
Z-offset
The fine distance adjustment between the nozzle and the build plate during the first layer. A correctly tuned Z-offset produces a slightly squished first layer for good adhesion. Adjusted via babystepping during the first layer.
Z-wobble
A print defect where the printed walls show a wavy, periodic horizontal displacement. Caused by a bent Z-axis lead screw, rigid coupling between the screw and motor, or eccentric Z-bearings. Fix with a flexible (oldham) coupling that decouples small lead-screw eccentricity from the motor shaft, and verify the lead screw runs true.
Keep learning
This glossary is updated periodically as the 3D printing landscape changes. For deeper coverage of specific topics, see our guides:
If you are buying your first printer, start here.
The slicer is the bridge from a 3D model to a finished print.
Where to find 3D models worth printing.
For miniatures, jewellery, and other high-detail work.
Or read our foundational explainer: What is 3D Printing?