Precision-Turned Parts for Reliable Fit and Function
Custom shafts, pins, bushings, sleeves and threaded components—manufactured to your drawings.
GPT Precision provides CNC turning services for metal and engineering-plastic parts, from prototypes to repeat production orders.
We connect turning operations, secondary features, finishing and inspection with the diameters, bores and mating surfaces that matter in your assembly.
CNC turning is a natural manufacturing choice for many components built around a central axis. It produces cylindrical surfaces, bores, shoulders, grooves and threads, but the relationships between these features often determine how the finished part performs.
We manufacture custom turned components according to their geometry, material specifications and functional requirements.
Shafts, locating pins and stepped components for positioning, supporting and connecting mechanical assemblies.
Key features: Bearing journals, mating diameters, shoulders, retaining grooves and end features.
What matters: Fits, datum relationships, runout and straightness where specified.
Cylindrical components used to establish alignment, clearance, separation and support between mating parts.
Key features: Internal bores, outside diameters, end faces, flanges and chamfers.
What matters: Bore-to-OD relationships, wall thickness, end-face geometry and dimensional stability during machining.
Threaded shafts, fittings, connector bodies, valve stems and related cylindrical components.
Key features: Internal and external threads, grooves, sealing lands, shoulders and specified passages.
What matters: Thread engagement, functional diameters, sealing surfaces, intersecting features and burr requirements.
These examples represent typical turned-part applications. The manufacturing approach is determined by the complete drawing and project requirements.
A turned component may require several machining operations to achieve its finished geometry. Planning these operations together helps address workholding, feature access and critical dimensional relationships.
External profiles, stepped diameters, shoulders, tapers, grooves and external threads.
Workholding and machining sequence are considered alongside the relationships between functional diameters and reference surfaces.
Facing, drilling, boring, internal turning, grooves and internal threads.
Bore depth, accessibility, wall thickness and the relationship between internal and external features can influence the machining approach.
Some turned components also require flats, slots, cross-holes or other non-rotational geometry.
Suitable features may be produced with live tooling where the machine configuration and tool access allow. Other designs require secondary milling, drilling or a separate setup.
The goal is a suitable machining sequence—not simply the fewest setups.
For components with critical relationships between features, the proposed process should account for how those relationships will be maintained and verified.
Not every round part should be made using the same process.
The right approach depends on geometry, matériau, tolerances, feature access, workholding and production requirements.
| Part Characteristics | Process to Consider |
|---|---|
| Predominantly rotational geometry | le tournage CNC |
| Turned diameters with flats, slots or cross-holes | Turning with suitable live tooling or secondary milling |
| Small or slender parts requiring support close to the cutting area | Swiss-type machining |
| Predominantly non-round geometry with multiple faces or pockets | CNC milling |
A small diameter does not automatically require Swiss-type machining, just as a round profile does not eliminate the need for milling.
GPT Precision evaluates the complete component before establishing the manufacturing approach.
Related Service: Swiss-Type Machining Services
We machine commonly specified metals and engineering plastics for custom turned parts.
Material selection and machining requirements depend on the specified grade, supplied condition, component geometry and intended application.
For components where weight, dimensional requirements and surface treatment considerations influence material selection.
For turned components with specified mechanical properties, wear requirements, corrosion resistance or material conditions.
For components where electrical, thermal, bearing, connection or other material properties are relevant.
For components requiring specified titanium grades and material conditions. Manufacturing feasibility depends on the complete part requirements.
POM/acetal, nylon, polycarbonate, ABS, PTFE and PMMA/acrylic are among the material families available for project discussion.
Plastic machining requires consideration of material behavior, wall thickness, workholding and the specified finished dimensions.
Material specification
Please identify the exact grade, applicable standard and supplied condition. Listed materials are not a statement of stock availability. Any proposed material substitution requires customer review and approval.
The finished component—not only the freshly turned surface—must meet its agreed requirements.
Bearing seats, sliding diameters, sealing surfaces and visible areas may require different dimensional and surface conditions.
Identify the shaft and bore fits, functional surface texture, edge conditions and any dimensions that must remain within tolerance after finishing.
Some components require grinding, heat treatment or other operations after turning.
Where specified, the machining allowance, process sequence, feature relationships and final inspection requirements are considered together.
Surface treatments may be supplied or coordinated according to the material and agreed project scope.
Specify any threads, bores, sealing areas or mating surfaces requiring protection during treatment.
Confirm the required acceptance condition: as-machined, after heat treatment or after final surface treatment, as applicable.
For precision-turned components, individual dimensions matter—but so do the relationships between them.
Inspection planning should reflect the component's function, drawing requirements and finished condition.
Verify specified shaft and bore dimensions, critical lengths and mating features using appropriate measurement methods.
Evaluate runout, straightness and other specified geometric relationships with reference to the drawing datums.
Identify thread acceptance requirements, groove dimensions, relief features and relevant burr or edge requirements.
Confirm the surface condition and any dimensions requiring verification after grinding or treatment.
GPT Precision's inspection resources include CMM, optical measurement and conventional dimensional and functional gauges. Measurement methods, inspection scope and required records are defined according to the project.
If inspection reports, material documents or special gauges are required, please identify them during quotation.
Related Page: Qualité & Inspection
CNC turning is generally suited to features arranged around a rotating axis, such as diameters, bores, shoulders and threads.
CNC milling is commonly used for flat faces, pockets, slots and non-round profiles.
Some components require both processes. The complete drawing helps determine the appropriate combination and machining sequence.
For suitable components, live tooling can produce certain flats, cross-holes, slots and other secondary features within a turning setup.
Whether this is practical depends on machine configuration, feature accessibility, workholding and drawing requirements.
A part with both turned and milled features does not automatically qualify for one-setup machining.
Swiss-type machining is useful for certain small or slender components that benefit from support close to the cutting area.
Part geometry, matériau, tolerances, secondary features and quantity also influence the choice.
There is no universal diameter or length-to-diameter ratio that determines the preferred process for every component.
Achievable tolerances depend on the part geometry, matériau, workholding, machining sequence and finished condition.
Share the drawing with critical diameters, fits, datums, geometric tolerances and surface requirements.
We evaluate these requirements before confirming the proposed manufacturing and inspection scope.
Inspection records and supporting documentation can be discussed as part of the project requirements.
If a special mating gauge or inspection fixture is required, include its specification and acceptance criteria in the inquiry.
The availability, supply scope and delivery requirements are confirmed during project review.
Have a custom shaft, bushing, sleeve or threaded component to manufacture?
Send your current drawing and available 3D model, together with the information needed to evaluate the complete part.
GPT Precision can review your requirements, clarify manufacturing questions and discuss a suitable machining and inspection scope before quotation.
