Basics
CADkyado
Computer-Aided Design
Work and software for creating, editing, and compiling into documents such as drawings the shape of a product (a flat drawing or a solid model) on a computer. CAM and CAE start from the shape data created here.[1][2]
On the shop floorIt is the source data from which CAM calculates the toolpath, so shape errors and missing faces lead directly to cutting mistakes.
Common misconceptions“If you have CAD, the machine runs” → CAD only creates the shape. The commands that move the machine are made by CAM and the post-processor.
CAMCAE2D CAD and 3D CADSolid model
Basics
CAMkyamu
Computer-Aided Manufacturing
Using software to create the commands (such as G-code) that run a CNC machine tool. In the broad sense, it includes machining planning, preparing the model, simulation, post-processing, and sending the program to the shop floor.[3][4][5]
On the shop floorEven for the same shape, the choice of tool, path, and conditions changes machining time and finish significantly. CAM lets you try those choices on screen.
Common misconceptions“CAM automatically creates the optimal machining” → People choose the path type, tool, and conditions. Automation features are tools that cut down that effort.
CADToolpath (tool path)Post-processor (post)NC program (G-code, NC data)
Basics
CAEshi-e-i
Computer-Aided Engineering
Using software to simulate a product’s performance (strength, heat, flow, and so on) and check whether the design is good. It proceeds in three steps: pre-processing (entering the shape, materials, and loads), calculation, and post-processing (viewing the results).[6]
On the shop floorChecking strength and deformation at the design stage reduces the number of prototypes and rework. On the machining side, know it by name as the third tool alongside CAD and CAM.
CADCAM
Basics
CAPP (computer-aided process planning)kyappu
Computer-Aided Process Planning / CAPP
Deciding, with the help of a computer, the process from raw stock to finished shape (which machine, in what order, and how to cut). There are two approaches: the “variant” type, which retrieves and edits the process plan of a similar part, and the “generative” type, which builds a new plan from the shape and rules.[7]
On the shop floorWhere skilled process planners are in short supply, it is the foundation for standardizing and automating how processes are decided.
Common misconceptions“CAPP is another name for CAM” → CAM mainly creates toolpaths and NC programs. CAPP comes before that and decides the sequence of operations.
CAMSetup (job)Feature recognition (recognizing machining features)
Basics
2D CAD and 3D CADnijigen kyado, sanjigen kyado
2D CAD / 3D CAD
2D CAD draws shapes with flat lines, like a paper drawing. 3D CAD creates solid models and can calculate volumes and check for interference between parts.[1][2][10]
On the shop floorA 3D model is needed for CAM to calculate toolpaths on curved surfaces. With only a 2D drawing, you have extra work rebuilding the shape before CAM.
Common misconceptions“With a 3D model, you don’t need a drawing” → There is an approach that carries tolerances and other data in the 3D model (MBD), but a shape-only model does not convey tolerances.
CADSolid modelMBD (model-based definition)PMI (product and manufacturing information)
Shape data
Solid modelsoriddo moderu
solid model / solid body
A model that represents the shape as a filled-in solid. You can calculate volume and weight, and obtain cross-sections when cut by a plane. Many CAD systems represent a solid by the connectivity of the faces, edges, and vertices that enclose it (B-rep).[10][11][12][13]
On the shop floorStock-remaining calculations and collision checks can be done reliably with a solid whose faces close with no gaps. For data you receive, first check that it is a solid.
Common misconceptions“If it looks 3D on screen, it’s a solid” → If even one face is missing, it is treated as a set of unclosed faces (a surface model).
Surface modelMesh model (polygon)B-rep (boundary representation)Neutral format (intermediate file)
Shape data
Surface modelsafesu moderu
surface model / surface body
A model that represents shape with faces that have no thickness alone. It has no interior (volume), but makes it easy to create complex curved surfaces such as exterior panels and molds. In practice it is often combined with solids.[10][14]
On the shop floorWith face-only data, there are cases where CAM has difficulty judging whether there is material inside. Before creating paths, check whether it can be made into a closed solid.
Common misconceptions“Volume and weight come out even from a surface model” → It has no closed volume, so they can’t be obtained as is.
Solid modelMesh model (polygon)
Shape data
Mesh model (polygon)messhu moderu
mesh / polygon mesh / triangle mesh
A model that approximates the surface with a collection of small triangles. 3D scan and 3D printer data (such as STL) take this form, and it carries no exact circle or plane information.[15][16][12]
On the shop floorBecause there is no cylinder or plane information, CAM operations that pick hole centers or planes are hard to use as is. Depending on the CAD, you can choose between a conversion that turns the triangles directly into faces and one that regroups them into planes and cylinders.
Common misconceptions“Once you import an STL, you can treat it like a solid” → STL is a set of triangular faces and carries no units. Check on import whether it is mm or inches.
STL (triangle mesh)Solid model
Shape data
Feature (history-based modeling)ficha
feature / parametric feature / history-based modeling
A unit of shape creation that has meaning, such as extrude, hole, or fillet. History-based (parametric) CAD records features in the order they were created, and changing a dimension rebuilds the later features.[17][18][19]
On the shop floorBecause the model follows when you change a dimension, in software where CAD and CAM are integrated, rebuilding paths after a design change is easier.
Common misconceptions“If you receive it as STEP, the history comes too” → Receiving from another company’s CAD in a neutral format normally gives you the shape only. Editing the shape without history is direct editing.
CADFeature recognition (recognizing machining features)Neutral format (intermediate file)
Data
Neutral format (intermediate file)chūritsu keishiki
neutral format
A common format for exchanging geometry between different CAD and CAM systems. STEP and IGES are typical.[45][46][47]
On the shop floorEven if you use a different CAD from your customer, you can bring the shape into CAM by receiving it in a neutral format.
Common misconceptions“Anything transfers in a neutral format” → The information that carries over (colors, tolerances, history) differs by format and export settings. After import, check for missing faces.
ISO 10303 (STEP)STEP AP242Feature (history-based modeling)
Data
STL (triangle mesh)esu-ti-eru
STL / triangle mesh
A file format that represents the surface as a collection of triangles. It has no standard for units or color.[16]
On the shop floorIt shows up when exchanging data with 3D printers and scanners. When cutting in CAM, check the units and decide whether conversion to a solid is needed.
Common misconceptions“STL is a CAD format” → It is an approximation of shape and carries no exact circle or plane information.
Mesh model (polygon)Neutral format (intermediate file)
Basics
Setup (job)settoappu
setup / job
A group of machining operations done in one setup. It holds information on the stock, coordinate system, and the machine and tools to be used, and the machining operations are arranged within it in order.[4][27]
On the shop floorA new setup and origin are needed each time the part is flipped or re-fixtured. The number of workholding changes is the number of CAM setups.
Work coordinate system (WCS)StockToolpath (tool path)
Coordinates and setup
Work coordinate system (WCS)waku zahyokei
work coordinate system / WCS / workpiece coordinate system
A coordinate system placed to suit the part. The CAM WCS is the reference for the coordinates in which the post-processed NC program is output, and on the machine you match it by registering it in G54 and so on.[20][21][22]
On the shop floorIf the CAM origin and the origin registered in the machine are off, everything is cut shifted even when the paths are correct. It is one of the main causes of first-run crashes.
Common misconceptions“Either Z direction is fine” → Fusion explains that the Z axis should point away from the surface being cut (toward the tool side).
Machine coordinate systemProgram origin (work origin)Handling workpiece measurement (touch probes) in CAMG54–G59 →
Coordinates and setup
Machine coordinate systemkikai zahyokei
machine coordinate system
A coordinate system specific to the machine. Its origin is fixed by the machine, and the work coordinate system origin is registered as a position within this coordinate system.[21]
On the shop floorIt is the reference when registering the work origin and when moving to fixed positions on the machine side, such as the tool change position.
Work coordinate system (WCS)Program origin (work origin)G53 →
Coordinates and setup
Program origin (work origin)puroguramu genten
part zero / program origin / WCS origin
The point where the NC program coordinates become 0. In CAM you choose it from the model origin, a selected point, the corner of the stock box, and so on; on the machine you register the same point in the work coordinate system (G54, etc.).[20][21][22]
On the shop floorPlacing it at a point that is easy to pick up on the machine, such as a stock corner, the top face, or a hole center, speeds up setup and reduces errors.
Common misconceptions“The CAD origin is the program origin” → They can differ. You can set it separately in the CAM setup.
Work coordinate system (WCS)Machine coordinate systemStockHandling workpiece measurement (touch probes) in CAM
Coordinates and setup
Stocksozai
stock
The shape and size of the material before cutting. Entering it in the CAM setup reduces air cutting and can also be used to track the stock remaining after each operation.[4][23]
On the shop floorIf the stock isn’t entered correctly, roughing ends up mostly cutting air, or conversely rapids straight into where material exists.
Setup (job)In-process stock (tracking stock left)Clearance height (safe height, retract height, feed start height)
Coordinates and setup
Fixturejigu
fixture / workholding
Things that hold or support the part during machining (vises, clamps, chucks, and so on). If you also put the fixture model into CAM, simulation can find collisions.[20][4][24]
On the shop floorMost CAM operations don’t know the fixture exists, so rapid moves can hit it. Put the fixture into the model and check.
Common misconceptions“It didn’t collide in simulation, so the fixture is safe” → If you haven’t included the fixture, collisions with it haven’t been checked.
StockCollision checkRapid and cutting feed (G00, G01)
Coordinates and setup
Tool librarykōgu raiburari
tool library
A register holding the shape and dimensions of tools and holders, cutting conditions, and so on. Each CAM has its own, and you call it up when creating operations.[4][25][26]
On the shop floorRegistering conditions as well saves re-entering them each time and reduces variation between people. If you register the holder too, you can also check collisions of the neck and holder.
Common misconceptions“A tool library is the factory’s tool management” → The library is a register inside CAM. Management that covers inventory, storage locations, and tool life is the job of a tool management system.
Tool stick-out and holder collisionsTool managementTooling →
Conditions
Depth of cut (axial ap, radial ae)kirikomi
axial depth of cut (ap) / radial depth of cut (ae)
ap is how far the tool bites in the axial direction and ae is the radial amount. High-efficiency roughing and trochoidal milling take a small ae and a large ap.[36][37]
On the shop floorThe combination of depth of cut with feed and spindle speed sets the tool load and machining time. It is the first number you enter in the CAM conditions field.
Stepover (pitch)Keeping chip thickness constant (radial chip thinning)High-efficiency roughing (adaptive)
Conditions
Stepover (pitch)sutteppu ōbā
stepover / pick feed
The spacing between adjacent paths. It affects the height of the cusps (ridges) left on the finished surface.[38][36][39]
On the shop floorA narrower stepover gives a better surface but increases the number of paths and lengthens machining time. For finishing, work backward from the cusp height to decide it.
Cusp (scallop) heightDepth of cut (axial ap, radial ae)Surface-following machining (scallop, constant stepover)
Machining type
Roughing, semi-finishing, finishingarakako, nakashiage, shiage
roughing / semi-finishing / finishing
First remove most of the stock quickly with a large tool (roughing), then even out what is left (semi-finishing), and finally bring it to size and surface finish (finishing). In CAM you line up the operations in this order and leave a little stock in roughing.[37][38][41][4][42][43]
On the shop floorPrioritize speed in roughing and accuracy in finishing, and change the tool, conditions, and tolerance.
Common misconceptions“Roughing and finishing can use the same settings” → The approximation tolerance is also normally larger for roughing and smaller for finishing.
Stock allowance (stock left, finishing allowance)Rest machining (leftover machining)Tolerance and chordal error
Conditions
Stock allowance (stock left, finishing allowance)torishiro
stock to leave / allowance
The thickness of material deliberately left after machining. The amount left on walls (radial) and on floors (axial) can be set separately.[44]
On the shop floorLeave a little in roughing and bring it to size in finishing. Set it negative to cut an EDM electrode smaller by the spark gap.
Common misconceptions“With roughing at zero stock to leave, you don’t need finishing” → In places the tool can’t enter, or because of entry settings, some areas end up with more left than specified.
Roughing, semi-finishing, finishingRest machining (leftover machining)
Basics
Toolpath (tool path)tsūrupasu
toolpath / tool path
The route the tool’s cutting edge (or center) follows. CAM calculates it from the model, tool, and conditions.[4][27]
On the shop floorEven for the same shape, machining time and surface finish change with the path type (waterline, raster, etc.) and the stepover.
CAMCL dataSimulation (playing back the toolpath)
Conditions
Rapid and cutting feed (G00, G01)hayaokuri to sessakuokuri
rapid traverse (G00) / feed motion (G01)
Rapid traverse (G00) is moving at high speed without cutting. Cutting feed (G01, etc.) is moving while cutting at a set feed rate. CAM paths are output using these two in combination.[35][24][4]
On the shop floorBecause rapids assume no cutting, any stock or fixture in the way will be hit at high speed. Prevent this with clearance height and by modeling the fixture.
Common misconceptions“If you watch it in the CAM screen, rapids are safe too” → You will miss cases where the fixture isn’t included or the machine origin is off. Some machines have a first-run function that detects collisions during rapids and stops.
Clearance height (safe height, retract height, feed start height)FixtureNC program (G-code, NC data)
Conditions
Clearance height (safe height, retract height, feed start height)nigetakasa
clearance height / retract height / feed height
A set of heights that determine how far the tool rises before moving and where it switches to feed. In Fusion they line up from the top as clearance height, retract height, and feed height.[40]
On the shop floorToo low and the rapid hits fixtures and clamps; too high and non-cutting moves increase and take time.
Common misconceptions“Heights are fixed numbers” → They are usually set relative to the top of the stock, so changing the model or stock moves the heights automatically.
Rapid and cutting feed (G00, G01)FixtureDrilling cycles (canned cycles)
Verification
Simulation (playing back the toolpath)shimyureshon
toolpath simulation / stock simulation
Replaying tool motion on screen before cutting to check how the stock is cut away and to find collisions. There are levels: replaying the path inside CAM, machine simulation that also moves the machine, verification that reads the NC program itself, and drawing on the NC control’s screen.[27][31][4]
On the shop floorBefore a trial cut, it can find much of the stock left, gouging, and collisions.
Common misconceptions“I simulated it in CAM, so the NC program is correct too” → Playback inside CAM looks at the path before the post. It won’t find post errors.
Collision checkMachine simulationG-code-based and CL-data-based simulationNC verification software
Verification
Collision checkkanshō chekku
collision check / interference check
Checking before machining whether the tool and holder will hit the part, fixture, or machine.[32][33][34]
On the shop floorA collision can damage the tool, spindle, and part all at once. The range of safety depends on how far the objects (fixtures, machine body) were included in the model and checked.
Common misconceptions“No collision = safe” → Only what was put into the model was checked. If fixtures or the machine weren’t included, collisions with them are unknown.
FixtureTool stick-out and holder collisionsMachine simulation
Basics
Post-processor (post)posuto purosessa
post processor / post
Software that translates CAM path data into an NC program in the format of a specific machine and control. It absorbs differences in machine axis configuration and available G/M codes.[28][4][29]
On the shop floorEven with the same path, you don’t get a correct NC program unless the post suits the machine.
Common misconceptions“A distributed post can be used as is” → A generic post doesn’t necessarily suit your machine. Test a new post carefully.
CL dataNC program (G-code, NC data)Post customizationG/M-code dictionary →
Basics
NC program (G-code, NC data)enu-shi purogramu
NC program / G-code / NC data
Machining commands read by the NC control. They are written in G-codes (motion) and M-codes (spindle, coolant, etc.), and CAM outputs them through the post.[3][4]
On the shop floorThe NC program is what gets fixed on the shop floor. If you fix it only on the floor without fixing the CAM side, the changes disappear the next time you output from CAM.
Post-processor (post)DNC operationRapid and cutting feed (G00, G01)G/M-code dictionary →
Basics
DNC operationdi-enu-shi unten
DNC / drip feed / remote buffer operation
Running while sending NC data from an external device (DNC / drip-feed operation). Used for large programs that don’t fit in the NC control’s memory (such as 3D finishing).[30]
On the shop floorFine-stepover surface machining tends to produce large NC programs, so this is the way out when memory operation isn’t possible.
Common misconceptions“Just connect the cable and you can send” → If the communication settings (baud rate, etc.) or cable wiring don’t match the control, communication fails.
NC program (G-code, NC data)Tolerance and chordal error
Management & integration
PDM (product data management)pidiemu
Product Data Management / PDM
A system that manages CAD data, part information, manufacturing instructions, documents, and so on in a single database. It also manages who changed what and when (check-in/check-out), revisions, and approval status.[9][8]
On the shop floorYou can check afterward “which revision of the model was used to cut,” which prevents the mistake of cutting from an old revision.
Common misconceptions“PDM = PLM” → PDM manages mainly design data. PLM covers the whole life of the product and lies beyond an expanded PDM.
PLM (product lifecycle management)CAD
Management & integration
PLM (product lifecycle management)pierumu
Product Lifecycle Management / PLM
The idea, and software, of managing information and workflows from product planning and design through manufacturing, maintenance, and disposal across departments in one system. It began with protecting CAD files and managing revisions, and now handles process and quality information too.[8][9][5]
On the shop floorConnecting CAM and PLM lets the shop floor use the correct revision of the model and standard tools and conditions (per Siemens).
Common misconceptions“PLM is the name of a piece of software” → It is also an idea (strategy) of managing a product’s whole life. PDM is its foundation.
PDM (product data management)MES (manufacturing execution system)Digital twin
