Plain definitions of the machining terms and CAM Assist names you'll meet in the CAM Assist window and in this help center, with the formulas CAM Assist uses for feeds, speeds and removal rates. Terms are in alphabetical order; UI names are in bold as they appear on screen.
Jump to: Numbers · A · B · C · D · E · F · G · H · I · M · O · P · R · S · T · U · W
Numbers
3 Axis A machining mode. CAM Assist machines the setup from one direction, moving the tool in X, Y and Z with its orientation fixed. See What are 3 Axis, 3+1 and 3+2 machining modes?
3+1 A machining mode. CAM Assist indexes the part around one rotary axis (the Axis of rotation, X or Y) to fixed positions, then machines each position in 3 axis. See Set the rotation axis for 3+1 machining.
3+2 A machining mode. CAM Assist tilts the part to fixed orientations with two rotary axes, then machines each orientation in 3 axis. The rotary axes don't move while cutting. See Choose machining directions for a 3+2 setup.
A
Adaptive roughing A roughing strategy that keeps the tool's engagement steady while clearing pockets and open areas, so it can cut deeper at a high feed. One of the usages a tool can be allowed for.
Allowed usages The operations a tool may be used for, such as Adaptive roughing, Drilling or Wall finishing. CAM Assist only picks a tool for an operation it allows. See Set a tool's allowed usages and stock materials.
Assessment The stage where CAM Assist checks the part model, stock and setups and lists machinability issues. You also choose the machine, material and configuration there. See The CAM Assist stages.
Avoidance geometry Bodies in your part file that the tools must stay clear of, other than the workholding. You select them per setup in the Setups stage. See Select avoidance geometry and workholding.
Axial stock to leave Material left on floors (along the tool axis) after roughing, for finishing to remove. Set on the Roughing tab of the configuration. See Configuration settings.
B
Break point In the Cutting Parameters Explorer, how close the stress in the tool gets to its limit, as a percentage. Lower is safer. See What do the Cutting Parameters Explorer measures mean?
Burr A small raised edge or sliver of material left on the part by milling or drilling. Removed by deburring.
C
CAD Computer-aided design: software for creating the 3D model of a part.
CAM Computer-aided manufacturing: software, such as Autodesk Fusion, Mastercam, Siemens NX, GibbsCAM or SolidCAM, that turns a part model into toolpaths and a CNC program. CAM Assist runs inside your CAM package.
Chamfer An angled edge cut on a part, usually to remove a sharp corner. Cut with a chamfer mill.
Chip breaker A feature on a tool's cutting edge that bends and breaks the chip into short pieces, so chips clear easily.
Chip Load The thickness of the chip each cutting edge actually removes. When the width of cut is less than half the tool diameter, the chip is thinner than the feed per tooth (radial chip thinning):
- Width of cut is half the diameter or more: chip load = feed per tooth
- Width of cut is less than half the diameter: chip load = feed per tooth × √(1 − (1 − 2 × width of cut ÷ tool diameter)²)
This ignores the tool's corner radius, so it's an approximation.
CNC Computer numerical control: a machine tool whose movements are driven by a program.
Coating A thin, hard layer on a tool that improves wear resistance and heat resistance. The coating affects which cutting speeds suit the tool.
Coolant Fluid or air that cools and lubricates the cut and clears chips.
Configuration A saved set of settings CAM Assist uses for a part: cutting parameters aggression, clearances, stock to leave, finishing and holemaking settings. You choose one in Assessment and manage them in My Shop > Configurations. See Configuration settings.
Corner radius The radius at an internal corner of a part. A round tool always leaves a radius at least as large as its own radius in an internal corner.
Cutting parameters The feeds and speeds for a tool in an operation: spindle speed, feed rate, step over, step down and so on. CAM Assist calculates them (AI-driven cutting parameters) or takes them from your presets. See What is a cutting parameter preset?
Cutting Parameters Explorer The window where you trade cycle time against tool load for one operation and see the effect on each measure. See The Cutting Parameters Explorer.
Cutting speed See Surface speed.
Cycle time How long the program takes to run. CAM Assist shows an Estimated cycle time, adjusted by the machine's scale factor. See How accurate is the cycle time estimate, and how do I set the scale factor?
D
Deburring An operation that breaks sharp edges and removes burrs, with a chamfer mill (angled edge) or a ball mill (rounded edge).
Depth of cut (Ap) How far the tool engages along its own axis on each pass (axial engagement).
Drilling Making a hole by plunging a rotating drill along its axis.
E
Excluded faces Faces outside the area CAM Assist was asked to machine, for example faces you didn't select with Finish full part cleared, or faces no operation covers after you delete one. See Why didn't CAM Assist finish some faces?
F
Face milling Machining a large flat surface, usually the top of the stock, often with a face mill (shell mill).
Feature planning The stage where you review the hole groups CAM Assist found and choose which setups machine them. See The CAM Assist stages.
Feed per tooth (fz) How far the tool advances for each cutting edge that passes:
Feed per tooth = feed rate ÷ (spindle speed × number of cutting edges)
Feed rate How fast the tool travels through the material (table feed), in mm/min or in/min:
Feed rate = feed per tooth × number of cutting edges × spindle speed
Finishing The final cuts that bring a surface to size and finish. CAM Assist creates flat, wall, chamfer, T-slot and freeform finishing operations.
Flat finishing Finishing flat, horizontal surfaces such as pocket floors and steps.
Flute length The length of the cutting part (flutes) of a tool, from the tip to where the flutes end.
Freeform finishing Finishing curved 3D surfaces, usually with a ball end mill, using passes such as contour, scallop or blend.
G
GD&T Geometric dimensioning and tolerancing: a standard way to state the allowed variation of a part's form, orientation and position on a drawing.
H
Helical boring Making or enlarging a hole by moving a milling tool down in a helix, rather than plunging straight in.
Helix angle The angle of a tool's flutes relative to its axis.
Hole group Holes CAM Assist found on the part, grouped by shape so they're machined the same way. See Review hole groups.
I
Inch 1 inch = 25.4 mm. To switch CAM Assist's units, see Switch between mm and inches in CAM Assist.
Include and Leave out The buttons on each operation in Program, with matching switches on each setup and section. Only included operations are sent to your CAM package. See Which operations get sent to my CAM package?
M
Machine group In Mastercam, the group in the Toolpaths Manager that holds a machine definition, its stock and its toolpaths. See CAM Assist won't start in Mastercam: machine group, stock or Master Model errors.
Machining directions For a 3+2 setup, the directions CAM Assist roughs and finishes from: Automatic, X, Y, Z aligned, Select (you pick them with Select directions), or (for finishing) Same as roughing. See Choose machining directions for a 3+2 setup.
Machining mode How CAM Assist machines a setup: 3-axis, 3+1 or 3+2. Set per setup with Mode in the Setups stage.
Material The stock material of the part. CAM Assist uses it to pick tools and calculate cutting parameters. See Add or edit a material in CAM Assist.
Material removal rate (MRR) The volume of material removed each minute:
- Milling: MRR = feed rate × depth of cut × width of cut
- Drilling: MRR = plunge feed rate × π × (drill diameter ÷ 2)²
With lengths in mm and feed in mm/min, divide by 1,000 to get cm³/min. The milling formula ignores the tool's corner radius.
MMC Maximum material condition (GD&T): the size of a feature when it holds the most material, for example the smallest hole or the largest pin within tolerance.
My Shop Where you set up the machines, materials, tool libraries and configurations CAM Assist uses. Open it with My Shop in the header. See My Shop.
O
Operation One step of the program: a tool, its cutting parameters and a toolpath. CAM Assist lists its operations in the Program stage. See The Program stage.
P
Partial and Rest Names CAM Assist adds to finishing operations when one tool can't finish a face completely: - Partial does what it can, - Rest cleans up the rest. See What are Rest and Partial finishing operations?
Plunge feed per rev How far a drill or tap advances into the hole for each revolution:
Plunge feed per rev = plunge feed rate ÷ spindle speed
Plunge feed rate How fast the tool moves along its axis while plunging, in mm/min or in/min:
Plunge feed rate = plunge feed per rev × spindle speed
PMI Product manufacturing information: dimensions, tolerances and finishes stored in the 3D model.
Pocketing Clearing material from a pocket or slot where the tool cuts on both sides.
Preset A saved set of cutting parameters for one tool doing one usage, optionally on one material. See What is a cutting parameter preset?
Program The operations CAM Assist generated for your part, with tools and cutting parameters. Also the stage where you review, edit and send them. See The Program stage.
R
Radial stock to leave Material left on walls (across the tool axis) after roughing. Set on the Roughing tab of the configuration.
Ramp angle How steeply the tool descends when it ramps or helixes into the material.
Ramp feed rate The feed used on the angled or helical move into the material.
Roughing Removing most of the stock quickly, leaving stock to leave for finishing.
S
Scale factor A percentage on each machine that CAM Assist multiplies its machining time estimates by, to match real cycle times. See How accurate is the cycle time estimate, and how do I set the scale factor?
Session tools The tools in the part open in your CAM package. They're available while that part is open. See Save session tools as a tool library.
Setup One way the part is held and machined: its orientation, stock and workholding. CAM Assist reads setups from your CAM package. See Set up your setups for CAM Assist.
Shell mill A face mill with replaceable inserts around its edge, used to machine large flat areas.
Spindle power The power the spindle delivers to the cut, in kW or hp. See What spindle torque and power should I enter for my machine?
Spindle speed How fast the spindle turns, in rpm.
Spindle torque The twisting force at the spindle, in N·m or ft-lb.
Spring pass An extra finishing pass along the same path, to remove material left by tool deflection on the first pass.
Step down The vertical distance between successive passes.
Step over The sideways distance between neighboring passes.
Stage One step of working through a part in CAM Assist: Overview, Assessment, Setups, Feature planning, Tools or Program. See The CAM Assist stages.
Stickout How far the tool protrudes from the holder. Set in the tool assembly editor. See The tool assembly editor.
Stock The raw material the part is machined from. The part must sit fully inside it. See "The part is not fully enclosed in the stock" in CAM Assist.
Surface roughness (Ra) How rough a machined surface is, given as an Ra value (in µm when you work in mm).
Surface speed (Vc) How fast the cutting edge moves past the material:
Surface speed (m/min) = spindle speed (rpm) × π × tool diameter (mm) ÷ 1,000
T
Tapping Cutting an internal thread with a tap. The thread pitch sets the feed.
Tool assembly A cutting tool together with its holder, tool number and stickout. See The tool assembly editor.
Tool deflection How far the tool bends under cutting force. The Cutting Parameters Explorer shows the mean deflection of the tool tip.
Tool holder The part of the assembly that grips the tool and fits the spindle. See Edit a tool holder in CAM Assist.
Tool library A collection of tools CAM Assist can program with. You choose which libraries to use for a part in the Tools stage, and manage them in My Shop > Tool libraries. See Add or remove tool libraries for a part.
Toolpath The path the tool follows to machine part of the part.
U
Unfinished faces Faces CAM Assist couldn't finish completely with the tools and setups it had. Program shows how many there are. See Why didn't CAM Assist finish some faces?
Usage What a tool is doing in an operation, such as roughing, finishing, ramping or drilling. Presets and allowed usages are set per usage.
W
Wall finishing Finishing vertical walls and the sides of features.
Width of cut (Ae) How much of the tool's diameter engages sideways in the material (radial engagement).
Workholding The vise, clamps or fixture holding the part. See Select avoidance geometry and workholding.
Workholding security How firmly a setup holds the part, as the largest sideways cutting force the clamping can take. Set per setup in the Setups stage. See What is workholding security in CAM Assist?