The cost of a high-volume machined part depends on more than raw material and quantity.
Part geometry, tolerances, material, secondary operations, inspection requirements and production volume can all affect how efficiently a component can be manufactured.
When thousands—or millions—of identical parts will be produced, small design decisions can have a significant impact on the manufacturing process. That is why Design for Manufacturability (DFM) is especially important for recurring high-volume production.
Quick Answer: What Makes a Machined Part More Expensive to Produce?
Several factors can increase the complexity or cost of producing a precision-machined component:
- Complex geometry
- Tight tolerances
- Difficult tool access
- Deep holes, threads and cross holes
- Material selection
- Multiple setups or machining operations
- Secondary operations
- Surface-finish requirements
- Inspection and documentation requirements
- Order quantity and annual production volume
DFM evaluates a part’s design and specifications in relation to the manufacturing process. The goal is to produce the required component efficiently and consistently without compromising its function or quality.
Why DFM Matters in High-Volume Production
A few additional seconds of machining time may seem insignificant on one component. Repeat that operation across 100,000 or 1 million parts, and the impact becomes much greater.
For high-volume machining, manufacturers consider not only whether a part can be made, but how efficiently and consistently it can be produced over the life of the program.
That can involve machine selection, tooling, cycle time, setups, secondary operations, inspection requirements and expected annual volume.
The objective is not simply to lower the piece price. It is to develop a reliable production process that can repeatedly meet the required specifications.
Tight Tolerances Should Be Used Where They Matter
Tolerances are essential to proper fit and function, but not every dimension requires the tightest possible tolerance.
Depending on the part and manufacturing process, tighter tolerances may require additional tooling, process control, inspection or different machining strategies.
A better engineering question is:
How tight does this tolerance need to be for the part to function correctly?
Clearly identifying critical dimensions helps the manufacturer focus process control and inspection where they matter most.
Part Geometry Can Affect Cycle Time and Tooling
Part geometry directly affects how a component can be machined.
Features that may require additional consideration include:
- Deep or difficult-to-access holes
- Thin walls
- Long or slender features
- Multiple diameters
- Internal or external threads
- Cross holes
- Tight internal features
- Features requiring secondary machining
No single feature automatically makes a part difficult or expensive to produce. Its impact depends on the overall design, material, tolerances, tooling access, equipment and production quantity.
For high-volume turned and screw-machined parts, reviewing these features early can help determine the most practical production method.
Material Selection Affects More Than Material Cost
Material choice can influence more than the cost of the raw stock.
Different materials can affect:
- Machinability
- Tool wear
- Cutting conditions
- Cycle time
- Surface finish
- Secondary finishing requirements
Avanti Engineering manufactures components from a range of raw materials, including steel, stainless steel, brass and aluminum, among others.
The material should first meet the functional requirements of the component. When more than one material is suitable, manufacturability can also be considered.
Secondary Operations Should Be Identified Early
Machining may be only one step in producing a finished component.
Depending on the drawing and application, additional processes may include:
- Broaching
- Slotting
- Grinding
- Heat treating
- Plating
- Part washing
- Thread locking
- Additional machining
- Light assembly
Identifying these requirements during quoting and process planning allows the complete production sequence to be considered before manufacturing begins.
Quality Requirements Affect Production Planning
Inspection and documentation requirements should be considered along with the physical design of the part.
Avanti Engineering’s Quality Assurance program includes ISO 9001:2015-aligned processes, C=0 acceptance sampling, SPC-driven in-process inspection and NIST-traceable measurement equipment.
Depending on customer requirements, Avanti can also support first-article/ISIR documentation, traceability and PPAP documentation when required.
For recurring production, quality planning helps maintain the required specifications throughout the production run rather than relying only on final inspection.
Production Volume Can Change the Best Manufacturing Method
The most efficient process for 1,000 pieces may not be the best process for 100,000 or 1 million pieces.
Avanti’s production capabilities include:
- CNC turning
- CNC Swiss machining
- Multi-spindle screw machining
- Automatic bar machining
The appropriate method depends on the combination of part geometry, material, tolerances, part size, required features, secondary operations and annual usage.
Higher recurring volumes may justify dedicated tooling, optimized setups or production equipment designed for repetitive manufacturing.
That is why order quantity and estimated annual usage are important when requesting a machining quote.
For a complete list of information to provide, see Avanti’s High-Volume Machining RFQ Checklist for OEMs. It covers drawings, quantities, material, tolerances, secondary operations, quality requirements and delivery expectations.
Before You Finalize the Drawing, Talk to Your Machining Supplier
Good DFM considers how the design, material, tolerances, manufacturing process, secondary operations, quality requirements and production volume work together.
Early manufacturing input can help identify potential production challenges while there is still an opportunity to address them.
Avanti Engineering specializes in recurring high-volume precision machining, with production capabilities for parts exceeding 1,000 pieces and extending into millions of pieces.
For the most useful project review, provide:
- Current drawing and revision
- Material specification
- Critical tolerances
- Order quantity
- Estimated annual usage
- Secondary-operation requirements
- Inspection and documentation requirements
Avanti can review the production requirements and determine which manufacturing process best fits the component and expected volume.
Send Avanti Engineering your drawing and production requirements to request a high-volume machining quote.
People Often Ask
What is DFM in machining?
Design for Manufacturability, or DFM, evaluates a part’s design based on how it will be manufactured. For machined components, this can include geometry, tolerances, material, secondary operations, inspection requirements and production volume.
Do tighter tolerances always increase machining cost?
Not always, but tighter tolerances can require additional tooling, process control or inspection depending on the feature and manufacturing process.
Why does production volume affect machining cost?
Higher quantities can change which equipment, tooling and setup strategy are most efficient. A process suited to 1,000 parts may not be the best approach for hundreds of thousands or millions of recurring parts.
When should an OEM involve a machining supplier in DFM?
Ideally, before the drawing and production process are completely finalized. Early review can identify geometry, tolerance, material or secondary-operation requirements that may affect high-volume manufacturing.