CNC TURNING & MILLING / CUSTOM PARTS
CNC Mill-Turn
Services
Turned precision.
Milled complexity.
CNC turning and milling services for custom shafts, fittings and housings. Combine turned surfaces with milled flats, slots and cross-holes, with finishing and inspection requirements reviewed from your drawing.
CNC Mill-Turn
Machining Capabilities
ProleanTech’s CNC mill-turn service combines turning with milling, drilling and tapping operations on an integrated machining platform. It suits parts that need cylindrical surfaces and off-axis features made in a coordinated machining sequence.
Turned diameters & faces
Machine outside diameters, faces, shoulders, bores, tapers and grooves for locating, rotating and mating surfaces.
Milled flats, slots & pockets
Add wrench flats, keyways, slots and accessible pockets to a turned body. Feature position and tool access determine the milling approach.
Axial & cross-holes
Add axial or radial holes and threaded features. Define hole position, angular orientation, usable thread depth and internal burr acceptance.
Feature-to-feature relationships
Control the relationship between turned and milled features by specifying functional datums, runout, position and orientation on the drawing.
Get a quote for your turned and milled part.
Upload your model and dimensioned drawing. Identify the features that must align so we can review workholding, tool access and the machining sequence.
When to Choose Mill-Turn
Over Separate Operations
Choose mill-turn when combining turning and milling can reduce part transfers or simplify control of related features. Compare it with dedicated turning, milling or separate operations using the complete drawing, batch quantity and finished-part requirements.
Start with your part’s geometry.
Select the closest description to see the first route worth reviewing.
CNC mill-turn machining
Consider mill-turn when flats, slots or cross-holes must align with a turned diameter or bore. Keeping related operations on one platform can reduce re-clamping and simplify datum control.
Review back-side access, gripping length, tool clearance and inspection access. Separate operations may be more economical for some geometries or batch sizes.
| Route | Best starting point | What to review |
|---|---|---|
| CNC mill-turn | A turned body with flats, slots, cross-holes or off-axis features. | Tool reach, workholding and relationships between the turned and milled features. |
| CNC turning | Primarily rotational features such as diameters, shoulders, grooves and axial bores. | Whether a dedicated turning route is sufficient for the complete drawing. |
| CNC milling | Prismatic parts, broad pockets and profiles with limited rotational geometry. | Access from multiple sides, fixture requirements and surface relationships. |
| Separate turning + milling | Parts better served by dedicated machines, tooling or independent operations. | Transfer datums, re-clamping error, inspection and batch economics. |
Combined operations do not always mean simultaneous cutting.
During conventional turning, the workpiece rotates against a cutting tool. During live-tool milling, the driven tool rotates while the workpiece is indexed or controlled as required. Simultaneous turn-milling is a specific cutting strategy; it is not required for every mill-turn part.
Compare machining routes for your drawing.
Send the drawing, quantities and final finish. Highlight critical datums so the review can compare setup requirements, feature control and the complete manufacturing scope.
Have a simpler rotational or prismatic component?
Typical CNC
Mill-Turn Parts
Common candidates include shafts with flats or cross-holes, threaded bodies with wrench features, and flanges with bores and bolt patterns. The assembly function determines which fits, datums and surfaces need the most attention.
Shafts & couplings
Turned journals with flats, keyways or cross-holes for motion and automation assemblies.
Review journal fits, runout and angular feature orientation.
Threaded bodies & fittings
Cylindrical parts with wrench flats, radial ports or internal bores for fluid and mechanical assemblies.
Define sealing faces, thread specification and intersecting-hole deburring.
Flanges, sleeves & housings
Bores and outside diameters combined with bolt patterns, slots or locating features.
Identify datum surfaces, bore fits and position requirements.
Show us which features control fit, location or sealing.
Materials for CNC
Turning and Milling
Choose a material for the part’s load, operating environment, mass and required surface. Specify the exact alloy or polymer grade and condition so the machining route, finishing and acceptance requirements can be reviewed together.
Compare CNC machining materials.
Use the Materials Hub to compare grade options, properties and machining considerations before specifying a material.
| Material family | Consider when | Decide before quoting |
|---|---|---|
| Aluminum alloys ↗6061 · 6082 · 7075 | Low mass, machinability and an anodized finish are priorities. | Alloy and temper, loading, cosmetic faces and coating allowance. Strength and corrosion behavior vary by grade. |
| Stainless steel ↗303 · 304 · 316L | Corrosion exposure and an unpainted metallic surface are key requirements. | Grade and condition, service environment, any welding requirement and passivation. Balance machinability with the required corrosion performance. |
| Carbon & alloy steel ↗C45 · 42CrMo4 | Strength, wear or heat-treatment requirements drive the design. | Hardness and heat-treatment sequence; corrosion protection; dimensions accepted before or after treatment. |
| Brass ↗CuZn39Pb3 | Machinability, conductivity or a threaded fitting design points toward brass. | Exact alloy, lead restrictions, fluid compatibility and any pressure-service acceptance requirements. |
| Titanium ↗Grade 2 · Grade 5 | Mass, corrosion performance or strength-to-weight requirements justify titanium’s processing cost. | Grade, loading, mating-surface galling risk and required documentation or application qualification. |
| Engineering plastics ↗ABS · PMMA · PC · PEEK · PP | Electrical isolation, low mass or a polymer contact surface is required. | Temperature, moisture, chemicals, creep, reinforcement and dimensional stability. Tight fits need service-condition review. |
The grades above are service-range examples. Material availability, stock form and substitutions are confirmed with the quote; specify any approval restrictions in your inquiry.
If the material is not fixed yet, tell us:
- Operating conditions: load, temperature, chemicals and moisture.
- Interfaces: sliding, sealing, electrical contact and mating materials.
- Constraints: mass, appearance, compliance and target cost.
Specify a grade or discuss a material choice.
Include the material grade and condition with your drawing. If the grade is open, share the operating conditions and target requirements for an engineering discussion.
Surface Finishing Options
for Mill-Turn Parts
Select a finish for corrosion protection, wear, appearance or surface cleanliness. Identify fits, threads, sealing faces and electrical contacts so masking, allowances and final inspection can be planned before machining.
Three questions before choosing a finish
- What must it do? Corrosion protection, wear resistance, color, texture or a clean metallic surface.
- What must stay unchanged? Bearing fits, thread engagement, sealing lands and datum surfaces.
- How will it be accepted? Final dimensions, surface roughness, appearance reference and any specified test.
A functional surface when a cosmetic treatment is unnecessary.
Material fit: Metals and suitable plastics
Drawing decisionSpecify roughness on sealing or sliding surfaces, edge breaks and burr acceptance. Visible tool marks can remain.
A uniform matte texture on exposed faces.
Material fit: Compatible metals; polymer suitability needs review
Drawing decisionIt is not a corrosion-protection coating. Protect close fits, threads and polished sealing faces; specify any following treatment.
Anodizing ↗
Colour, corrosion protection or a wear-focused aluminum surface.
Material fit: Aluminum alloys
Drawing decisionSpecify the process type, color and acceptance requirements. Oxide growth, pretreatment and contact marks require allowance and masking review.
Removal of free iron to support stainless corrosion performance.
Material fit: Suitable stainless steel grades
Drawing decisionIt is not a leveling process or a decorative coating. Define grade, cleaning, the required procedure and verification.
A deposited metal layer for a wear or corrosion requirement.
Material fit: Compatible metal substrates, subject to preparation review
Drawing decisionSpecify deposit requirements, thickness and any post-treatment. Include bores, threads and mating diameters in the allowance plan.
A colored protective coating on exposed surfaces.
Material fit: Suitable metal substrates
Drawing decisionConfirm pretreatment, color and texture. Mask fits, threads and grounding contacts; check part compatibility with the cure cycle.
A dark conversion finish where appearance and limited dimensional build are priorities.
Material fit: Compatible ferrous alloys
Drawing decisionSpecify the substrate, sealing or oiling and service environment. Do not treat black oxide alone as heavy-duty corrosion protection.
A fit-sensitive shaft, for example
If an aluminum shaft has an anodized visible body and a close-fitting bearing journal, identify the journal and datum faces for masking or allowance review. Specify whether the acceptance dimensions apply after finishing.
What to include in a finishing specification
Material + treatment + type or governing specification + thickness where applicable + color/texture + masking map + final dimensional and cosmetic acceptance.
Request machining and finishing in one quote.
Attach the finish specification and mark surfaces that must fit, seal or remain conductive. We will review the machining sequence, finishing scope and final acceptance requirements together.
Mill-Turn Design,
Tolerances and Inspection
Specify critical size, runout, position, roughness and thread requirements on a dimensioned drawing. Achievable tolerances depend on the material, geometry and finished condition; acceptance criteria and inspection scope are agreed for the project.
Design review priorities
- Functional datums: identify the axis and faces that locate the part in assembly.
- Critical tolerances: separate diameter size, runout, position and surface finish requirements.
- Tool access: review deep pockets, internal corners, slender sections and features near the chucking area.
- Final condition: specify heat treatment, coating, burr acceptance and protected surfaces.
Design features that affect machining and inspection
| Feature or requirement | Why it changes the route | What to define |
|---|---|---|
| Tight bore or bearing journal | Size, roundness, finish and final coating state can require different operations and gauges. | Fit, size tolerance, roughness and the finished condition. |
| Cross-hole relative to a turned axis | Position and angular orientation influence the datum and clamping plan. | Datum references, position and orientation requirements. |
| Long shaft or thin wall | Deflection, vibration and clamping distortion affect machining and measurement. | Full geometry, critical straightness or runout and allowable contact areas. |
| Intersecting holes or internal edges | Tool access and deburring may be harder than producing the visible surface. | Burr acceptance, fluid passages, edge breaks and inspection access. |
| Heat-treated or coated part | Distortion, growth or material removal can change the accepted dimensions. | Treatment sequence, hardness, allowance and final inspection state. |
QUALITY PLANNED WITH THE PART
Define inspection
and documentation upfront.
Identify critical-to-function dimensions and the drawing revision used for acceptance. Include dimensional reports, first-article requirements and material records in the inquiry so they can be scoped and quoted before production.
- Dimensional acceptance
- Apply drawing-specific tolerances to critical features and agree general tolerances for the remaining dimensions.
- Inspection documentation
- Request a dimensional report, first-article scope or other records; confirm availability and cost before ordering.
- Material documentation
- Specify the required certificate, traceability and any applicable acceptance requirements.
- Supplier verification
- View the published ISO 9001 certificate ↗ and confirm its scope, validity and any additional qualification requirements during supplier review.
Have a critical fit or documentation requirement?
Highlight critical features and list the inspection records you need. Include any required first-article approval or material traceability with the RFQ.
CNC Mill-Turn Cost:
What Affects Your Quote
CNC mill-turn cost depends on material, stock size, setup complexity, machining time, quantity, tolerances, finishing and inspection. Compare the total cost of an accepted finished part, including any secondary operations and required records.
Operations and access
Extra grips, custom soft jaws, special tools and difficult back-side access can matter more than the number of visible features.
Review:
Can features share a datum or tool approach without changing assembly function?
Geometry and acceptance
Deep features, slender sections and tight requirements on every surface can add cutting time and verification work.
Review:
Which dimensions control performance, and which can use an agreed general tolerance?
Quantity and repeatability
Programming and tooling are spread differently across a prototype, a production batch and a recurring order.
Review:
Share prototype quantity, repeat demand and drawing stability so the quote reflects the purchasing plan.
Make supplier quotes comparable.
Compare the same revision, material condition, quantity, finishing scope, inspection documents, packaging and delivery terms. A lower unit price may exclude operations or records your assembly requires.
How to Order
Custom Mill-Turn Parts
Send a complete RFQ for a project-specific review. Confirm the drawing revision, material condition, quantities, finishing, inspection documents and delivery requirements before placing the order.
Send your files
Share a STEP model and dimensioned PDF drawing, material grade, quantity, revision and requested delivery date.
Review the route
Discuss combined features, workholding, access, critical dimensions and any changes that could simplify manufacturing.
Confirm the scope
Agree material, operations, final finish, inspection documents, price and delivery schedule before ordering.
Manufacture & verify
Parts are produced to the agreed requirements. Confirm inspection records, protection, packaging and delivery arrangements.
Send your mill-turn RFQ.
Upload the current model and drawing with material, quantities and final finish. Flag the critical dimensions and quality documents that must be included in the quote.
CNC Mill-Turn
Service FAQs
Practical answers for engineering review and supplier selection.
What are CNC mill-turn services?
CNC mill-turn services combine turning with milling, drilling or tapping on an integrated machining platform. They suit parts with cylindrical surfaces and off-axis features, including shafts with flats, fittings with radial ports and flanges with bolt patterns.
When should I choose mill-turn instead of separate turning and milling?
Consider mill-turn when reducing transfers can simplify workholding or improve control of related features. Separate operations may be preferable for some geometries, tooling needs or quantities. Compare both routes using the complete drawing, final finish and inspection requirements.
Does mill-turn machining finish a part in one setup?
Mill-turn can reduce setups, but a finished part may still require back-side machining, spindle transfer, heat treatment, finishing or additional inspection. The drawing and access requirements determine the number of setups.
Which materials can I request for CNC mill-turn parts?
Material options include aluminum, stainless steel, carbon and alloy steel, brass, titanium and engineering plastics. Specify the exact grade, condition and stock requirements. Availability and suitability are confirmed with the quote; substitutions require agreement.
What tolerances can you achieve on mill-turn parts?
Tolerances are reviewed against the drawing, material, part size, geometry and final condition. Specify size, runout, position and surface roughness separately for critical features. Confirm the acceptance limits and inspection method in the quote.
What part sizes and wall thicknesses can you machine?
Send the complete model and drawing with the part envelope, wall thicknesses and critical dimensions. Feasibility depends on workholding, stiffness, tool reach and material. Size limits and thin-wall requirements are confirmed for the proposed machining route.
Can surface finishing be included in the machining quote?
Yes. Include the finish specification, masking map, cosmetic requirements and final dimensions with the machining inquiry. Options depend on the substrate and can include bead blasting, anodizing, passivation, electroless nickel, powder coating and black oxide.
Should drawing dimensions apply before or after finishing?
State the acceptance condition on the drawing. Coating build-up, pretreatment and material removal can affect fits and dimensions. Mark critical surfaces and specify masking, allowances and any requirements for final inspection after finishing.
What affects CNC mill-turn pricing and lead time?
Material availability, stock size, setup and tooling, geometry, quantity, tolerances, finishing and inspection affect pricing and delivery. Include prototype quantity, expected repeat demand and the requested delivery date for a project-specific quote.
What files do I need for a CNC mill-turn quote?
Send a STEP model and dimensioned PDF drawing with the revision, material grade and condition, quantities, finish, critical tolerances, inspection documents and requested delivery. Your files stay confidential, and an optional NDA can be arranged before you share sensitive information.
START WITH THE FEATURES THAT MATTER
Get a Quote for
Your CNC Mill-Turn Part
Upload your model and dimensioned drawing for a project-specific quote. Include the material, quantities, finish and inspection requirements, and identify the features that control fit, location or sealing.
Your files stay confidential. Privacy Policy ↗ · Optional NDA available ↗