01
Primary geometry
Separate rotational envelopes, prismatic faces, bores, cross-holes, slots and compound surfaces before selecting the base process.
Evidence route
Feature map and proposed primary process
Process route selection
CNC turning vs milling: choose from geometry, not habit.
Turning, 3-axis milling, multi-axis milling and combined mill-turn routes solve different access, setup and feature relationships. PartVerity frames the route around the controlled geometry, critical features, batch profile and evidence needed—not around a machine label alone.
Decision premise
Route question: which sequence creates the required features with the fewest uncontrolled transfers and a credible inspection method?
Engineering control
Six inputs before a machining route is released
A cylindrical part can still require milling; a prismatic part can still benefit from turning. The complete feature relationship decides the route.
02
Feature access
Review tool approach, undercuts, internal features and orientation changes that can create additional setups or specialist tooling.
Evidence route
Access review, setup count and tool-route assumptions
03
Datum continuity
Keep functional relationships in one setup where practical or define how datums are transferred and re-established between operations.
Evidence route
Datum scheme, setup references and transfer controls
04
Batch profile
Prototype learning, repeat volume and change likelihood affect fixture investment, bar strategy and combined-operation value.
Evidence route
Quantity profile, repeat assumption and fixture basis
05
Material behaviour
Machinability, work hardening, thermal movement, burr formation and stock condition influence route stability and tool strategy.
Evidence route
Material specification, stock form and route-specific risks
06
Verification route
Select a machining sequence that leaves critical characteristics accessible to a suitable measurement method and release record.
Evidence route
CTQ-to-method map and stage-specific inspection points
Decision matrix
Process choice by geometry and control need
The table is a route-screening aid. The drawing, material and supplier capability review remain controlling.
| Part condition | Likely route | Control focus |
|---|---|---|
| Predominantly rotational | Turning with secondary live-tool or milling operations where needed | Concentricity, runout, bore relationships and transfer control |
| Prismatic with accessible faces | 3-axis milling with planned reorientation | Datum transfer, clamping and setup-to-setup relationships |
| Multiple faces or compound access | 4/5-axis or indexed multi-axis route | Collision/access review, workholding and verified machine/supplier fit |
| Rotational plus dense milled features | Mill-turn or controlled multi-machine route | Single-route benefit versus specialist transfer risk |
| Simple part with unstable thin features | Route selected around support and stress management | Clamping distortion, sequence and post-release dimensions |
Claim boundaries
Shortcuts that weaken route selection
Assuming every round part is a one-operation turning job.
Choosing 5-axis because it sounds more capable without proving access or setup benefit.
Comparing hourly rates without comparing setup count and inspection effort.
Ignoring how the final datum and CTQs will be measured.
Technical context
Use guidance to frame the review—not to replace project evidence.
External design context for setup, geometry and machining-time trade-offs. Supplier-specific capability is confirmed only after drawing review.
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