Processes / Engineering reference
CNC milling
CNC milling removes material with a rotating cutter under programmed motion. Match the cutter and setup to the feature before choosing cutting parameters.
Engineering reference · Sources included
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CNC milling starts with the feature
CNC milling removes material with a rotating cutter moved under programmed control. For a slot or pocket, the first practical decision is whether the tool can reach the feature and cut it with adequate support. The cutter, fixture and cutting parameters must work together; programmed motion alone does not establish the result.
Sandvik Coromant's groove and slot milling guide distinguishes end milling for closed or curved slots from side-and-face milling for long, deep, open grooves. Width, depth and available equipment constrain the choice.
| Feature | Starting point for review | Question to resolve |
|---|---|---|
| Closed or curved slot | End mill | Can the cutter reach the whole feature? |
| Long, deep, open groove | Side-and-face cutter | Does the machine provide the required access and support? |
| Pocket wider than the cutter | End mill and planned toolpath | How will the remaining material be removed? |
This table narrows a process discussion. It does not select a particular tool or certify that a feature can be produced to the drawing.
Plan a stable cut
The same slot geometry can present different setup problems depending on how far the cutter projects from its holder and how the workpiece is supported. Sandvik recommends minimizing tool overhang where access permits and evacuating chips from the groove.
| Decision | Check |
|---|---|
| Access | Is the groove open or closed? Can the selected cutter reach it? |
| Stability | Can tool overhang be shortened and the workpiece supported? |
| Chip removal | Can chips leave the groove without being cut again? |
Use these as review prompts. If a fixture blocks access, resolve the fixture and operation sequence before treating the toolpath as ready for machining.
Keep CNC milling variables distinct
The Sandvik metric definitions use separate quantities for cutting speed, spindle speed and feed. Record the units with every value so that a speed setting cannot be mistaken for a feed setting.
| Quantity | Unit | What it describes |
|---|---|---|
| Cutting speed | m/min | Cutting motion at the cutter circumference |
| Spindle speed | rev/min | Cutter revolutions per minute |
| Feed per tooth | mm/tooth | Feed allocated to each cutting tooth |
| Table feed | mm/min | Feed motion per minute |
Use the tool maker's application data for the actual material, cutter and engagement. A parameter sheet should identify the stock condition, tool and operation alongside the values. This reference supplies no universal cutting recipe. For a 7075 part, continue with the material and drawing references in Related references before releasing the machining plan.
Entity relationships
- 7075 aluminum — milling connection — CNC milling
Editorial connection with qualification: Kaiser rates T6/T651 machinability as fair for rod/bar. Milling suitability requires the actual temper, stock, tool and setup; no universal capability is asserted.
Kaiser Aluminum: Rod & Bar Alloy 7075 — Technical Data, KA-RBH-7075-8.10Locator: Page 1: Alloy description and comparative characteristics.
Editorial process qualification: review feature geometry, cutter access, stability and chip removal when planning the cut. The guide is not a 7075-specific cutting recipe.
Sandvik Coromant: Groove or slot millingLocator: Groove or slot milling: cutter concepts; how to apply.
Sources
- Groove or slot millingSandvik Coromant · Primary referenceSupports: Slot geometry, tool choice, setup stability and chip removal.Locator: Groove or slot milling: comparison of cutter concepts; end milling; how to apply.
- Formulas and definitions for milling — metricSandvik Coromant · Primary referenceSupports: Metric definitions and units for cutting speed, spindle speed, feed per tooth and table feed.Locator: Metric formula sheet: designation/definition and unit columns.