01 / OPERATION
OD Turning & Facing
Straight and stepped diameters, end faces, tapers and profiles. Identify the functional surfaces and any transitions that must match a mating part.
Drawing-Based TurningMade for your part, not a fixed catalog
Metal & Plastic PartsMaterial grade agreed before production
Prototypes & Repeat BatchesQuote for the quantities you need
Direct Factory CommunicationKnow who will make your parts
CNC turning for shafts,
sleeves and precision fits.
A bearing seat, sealing surface or threaded connection can each require a different acceptance check, even on the same component.
Review drawing requirementsTurned geometry
01Functional diameters02Shoulder locations03Datum relationships
CNC lathe operations, matched to the drawing.
The drawing lets us confirm the tooling, workholding and any secondary operations before we accept the job.
02 / OPERATION
Boring & Internal Features
Provide bore diameter, depth and whether the hole is blind or through. Tool reach and chip clearance matter for deeper internal features.[2]
03 / OPERATION
Threads & Grooves
Specify the thread form, pitch, fit class and useful length. For grooves, show the width, depth, radii and the function they perform. The turning operations guide connects turning, facing, grooving and parting off to the finished features.
04 / OPERATION
Turning with Milled Features
Flats, keyways and cross-holes may need live tooling or a separate milling operation. The route depends on equipment, access and the drawing.[3]
Long slender parts, deep bores, small features or special alloys need a part-specific review. Swiss-type turning and grinding are not assumed to be part of every job.
Custom turned parts.
Made to your drawing.
Shafts & Stepped Spindles
Multiple diameters and shoulders for drive, locating or support functions.
Discuss: Bearing seats · shoulder spacing · datum axis
Bushings & Sleeves
Hollow cylindrical parts with a defined relationship between the bore and outside surface.
Discuss: Bore fit · wall thickness · surface condition
Flanges & Hubs
Round interfaces with faces, bores and optional mounting features. Hole patterns may add a milling step.
Discuss: Face location · bore alignment · bolt pattern
Threaded Adapters
Custom threaded connectors and adapters made to a defined mating specification.
Discuss: Thread form · fit class · usable thread length
Pins & Shoulder Pins
Locating and joining parts with controlled diameters, lengths and end details.
Discuss: Diameter fit · straightness · end geometry
Spacers, Rings & Collars
Round spacing and locating components designed around the dimensions of your assembly.
Discuss: Face spacing · bore clearance · edge treatment
Materials for
metal and plastic turning.
| Material / reference grade | Reference property |
|---|---|
| Aluminum 6061-T6 / T6511 extrusion | Yield strength ≥240 MPa |
| Stainless steel 304 / EN 1.4301 | Thermal expansion 16 × 10⁻⁶/K 20–100°C |
| Steel 42CrMo4 +QT, Ovako 327A Round bar, 40 < diameter < 100 mm | Hardness 270–320 HB |
| Titanium Ti-6Al-4V, annealed bar Section <76.2 mm | Yield strength ≥828 MPa 20°C, longitudinal |
| Brass C36000 free-cutting brass | Lead 2.5–3.0 wt% |
| Copper C11000 ETP copper | Electrical conductivity 101% IACS 20°C |
| Inconel alloys INCONEL 625, annealed rod / bar / plate Product sizes ≤4 in | Nominal hardness 145–220 HB |
| PEEK Unfilled TECAPEEK natural | Tensile modulus 4200 MPa 1 mm/min |
| POM / acetal POM-C, TECAFORM AH natural | Water absorption 0.05 / 0.10% 24 / 96 h, 23°C |
| Nylon PA6, TECAMID 6 natural | Water absorption 0.30 / 0.60% 24 / 96 h, 23°C |
| Acrylic / PMMA Clear cast PLEXIGLAS GS 0F00 | Light transmittance ≈92% D65, DIN 5036-3 |
Named-grade reference data: Hydro Alloy 6061; Outokumpu Core range; Ovako 42CrMo4; TIMET TIMETAL 6-4; Copper Development Association C36000 and C11000; Special Metals INCONEL alloy 625; Ensinger product data for the listed grades; Röhm PLEXIGLAS GS / XT. Polymer values are typical. INCONEL hardness is nominal comparative data. The references compare published material data; we confirm machining limits and any substitute grade against your drawing.
Need a different grade? Include the exact specification and required documentation. Substitutions require your approval.
CNC turning tolerances.
Defined by your drawing.
| Nominal diameter (mm) | H7 hole | h6 shaft |
|---|---|---|
| >3–6 | +0.012 / 0 | 0 / −0.008 |
| >6–10 | +0.015 / 0 | 0 / −0.009 |
| >10–18 | +0.018 / 0 | 0 / −0.011 |
| >18–30 | +0.021 / 0 | 0 / −0.013 |
| >30–50 | +0.025 / 0 | 0 / −0.016 |
Use the H7 hole or h6 shaft class where specified on the drawing; geometric controls are defined separately. ISO 286-2
Design guidance
for CNC turned parts.
Long, slender sections
Discuss supported length, workholding and whether center features are allowed. Slender sections can be sensitive to cutting forces and vibration; their acceptance criteria should be clear.[4]
Deep bores
Show the working bore length and internal geometry. Increasing tool overhang can make vibration, deflection and chip evacuation harder to control.[2]
Thin walls & rings
Define the important free-state dimensions and allowable clamping surfaces. Review how the part will be held, machined and inspected without changing the functional design.[4]
Threads near shoulders
Show usable thread length, mating engagement and any relief or runout permitted at the end. Do not rely only on a rendered CAD thread to convey the specification.
Grooves & sealing surfaces
Show groove width, depth, corner details and the sealing or retaining specification. Ask for a review of the required tool access and inspection method.
Cross-holes, flats & keyways
Mark angular relationships to other features. These details can need an additional setup or live tooling; confirm the route instead of assuming every feature is turned.[3]
Design changes are proposals for your review—not automatic edits to the part. Keep drawing revisions and approvals aligned before production.
Surface finishes
for your turned parts.
Inquiry preference: Not specified
Name the finishing process together with the surface specification it has to meet, and mark the areas that need a particular roughness or final dimension - we hold both.[4]
Inspection for fits, threads
and surface finish
Set acceptance before production
Identify critical dimensions, datums and any material or finishing records. Agree the inspection scope and reporting format as part of the order.
Match the method to the feature
Diameter measurements establish the shaft or bore size. Runout checks establish surface variation as the part rotates about the specified datum axis, which is a separate characteristic from diameter. Thread gauges check the specified thread system and fit class, while roughness measurement checks the stated surface parameter and measurement conditions. We agree the locations, method and reported results for each required characteristic.
Keep revisions and records aligned
For repeat batches, confirm the approved drawing revision, sample requirements, inspection frequency and the way parts or lots need to be identified.
Make responsibility explicit
When a partner process is needed, agree who performs the work, who checks it and who handles questions about conformity before the order is placed.
Turning costs
and order quantities
Prototypes
Programming and setup are shared across only a few parts, so preparation can outweigh the cost of each turning cycle.
A sample price should not be treated as the unit price of a production batch.Small-Batch Production
More parts share the setup cost, reducing its contribution per piece. Material, cutting time and secondary operations still contribute to each part.
The saving depends on the part geometry and the work required for each piece.Repeat Production
An unchanged part and process may allow an existing program and workholding method to be reused, reducing preparation compared with a new part.
Drawing, material or finish changes can require fresh preparation.What changes a turning quote?
Geometry, stock condition, tooling and secondary operations affect the turning cost. Initial and repeat quantities affect how setup cost is shared across the batch.
Material & starting stock
Exact grade, supplied condition, sourcing requirements and material removed from the starting shape.
Tooling & process route
Part geometry, workholding, tool access and secondary operations such as cross-drilling, milling or grinding.
Finishing & acceptance
Coatings, masking, required records and inspection scope.
Quantity & delivery
Setup shared across a batch, repeat-order scope, material availability and the requested delivery destination.
Minimum order quantity, lead time and shipping arrangements are confirmed for each project.
Industry applications
for turned parts
Aerospace
Bushings, sleeves and interface components. Confirm traceability and qualification requirements.
Application RequirementsMedical Devices
Instrument and assembly components. Specify material, cleanliness and documentation needs.
Application RequirementsAutomotive
Shafts, pins, spacers and adapters. Identify critical fits and repeat-batch requirements.
Application RequirementsDefense
Share qualification and information-handling requirements before exchanging restricted drawings.
Application RequirementsSemiconductors
Precision interfaces and equipment components. Discuss surface and cleanliness requirements.
Application RequirementsThe examples show the kind of work we take on. Tell us which sector approvals or certifications your program requires and we review them with you before accepting the project.
From drawing review to delivery
Share the specification
Send the CAD model, matching drawing, material, quantity and target delivery.
Review the route
Discuss fit, tooling, stock, finishes, inspection and any partner processing.
Approve the scope
Confirm price, revision, acceptance requirements and delivery arrangements in writing.
Make, check & deliver
Proceed to the agreed production, inspection, records and packaging plan.
Internal-feature control in a turned component
416 STAINLESS STEEL
Collimator tube with cross-holes
Small-hole checks and two-angle microscope inspection exposed burrs that main-bore gauging could otherwise hide.
Read the collimator tube projectCNC turning.
Your questions answered.
What is the difference between CNC turning and CNC milling?
Turning rotates the workpiece and is commonly used for round profiles, faces and diameters. Milling uses rotating cutters to create features such as pockets, flats and hole patterns. A part can require both processes.[1][3]
Can you make parts from my drawing rather than a catalog?
Yes—start with your own part specification. The examples on this page illustrate part families, not stocked items. Send your model and matching drawing so we can review the shape, material, quantity and acceptance requirements.
What tolerances and maximum part size can you accept?
These need a drawing-based review. Provide the outside diameter, total length, material, critical fits and geometric controls. The quote states the requirements we accept for your part, with every figure reviewed against its actual geometry and inspection scope.
Can you turn parts with threads, grooves and internal bores?
Include those features in the inquiry with their full dimensions and acceptance requirements. Thread forms, useful length, bore depth, groove access and the workholding arrangement all need review before the scope is confirmed.
Can a turned part also have cross-holes, flats or a keyway?
These features may be produced with live tooling or an additional milling setup. Mark their locations and angular relationships on the drawing. The quotation should identify the proposed process route, not assume all features are completed in one setup.[3]
Do you offer Swiss-type turning or grinding?
Swiss machining and grinding can be reviewed as separate requirements. Send the part dimensions, slender sections and surface requirements so we can discuss the appropriate route and any specialist involvement.
Can I order prototypes or a small batch?
Include the quantity you actually need and what the first parts must demonstrate. Minimum quantities, setup costs and any sample-approval stages are agreed for the project rather than advertised as one rule for every component.
How are the price and lead time determined?
The drawing, material condition, quantity, tooling, secondary operations, finish, inspection and delivery requirements define the scope. Share a requested delivery date; the achievable schedule and any dependencies are confirmed in the quote.
Will my part be made by your factories or by a partner?
Our first step is to review the fit with our factories. For work outside that fit, we can discuss coordinating suitable partners or making an introduction. Agree the manufacturing parties, inspection responsibilities and commercial relationship before placing the order.
What files should I send, and how do I handle confidential drawings?
A STEP or IGES model plus a matching PDF drawing is a useful starting point. Include units, part number and revision. The inquiry form accepts one file or a ZIP up to 20 MB. Agree confidentiality and an appropriate transfer method before sharing sensitive or restricted information.
Send the drawing. Start with the critical features.
- CAD model and matching drawing, with part number and revision.
- Material grade, finish and the quantity you need.
- Critical diameters, datums, runout, threads and inspection records.
- Delivery date, destination and any repeat-order plans.
Not ready to share confidential files? Start with a non-sensitive project description and state any confidentiality requirements.
PROJECT SUPPORT
Discuss your turned part
Share your drawing, material and quantity. Tell us what you need and we will reply by email.
Technical references & scope of guidance
References for turning processes and component quality.
- Sandvik Coromant — General turning
- Sandvik Coromant — Internal turning
- Protolabs — CNC turning design guidelines
- Sandvik Coromant — Turning component quality
