The make vs buy decision for precision machined components is one that manufacturing companies revisit repeatedly as their product lines, volumes, and capabilities evolve. There is no universal right answer – but there is a structured way to think through it, and there are situations where each approach is clearly superior.
This article lays out the real economics and operational considerations of contract CNC machining versus in-house production – without the marketing spin.
What In-House CNC Machining Actually Costs
The visible cost of in-house machining is equipment. A capable CNC turning center costs $80,000 to $200,000. A Swiss CNC machine costs $150,000 to $400,000. A 5-axis vertical machining center costs $250,000 to $600,000. These are purchase prices – the cost of the machines themselves before they produce a single part.
The invisible costs are where the real economics live:
- Operators – a skilled CNC machinist earns $50,000 to $80,000 per year plus benefits. A machining cell typically requires at least one operator per shift.
- Tooling – carbide inserts, end mills, drills, taps, and boring bars consume several thousand dollars per month per machine in active production
- Overhead – floor space at $8 to $20 per square foot annually, electricity, compressed air, coolant, and facility maintenance
- Setup time – every job change requires setup time during which the machine is not cutting parts
- Quality and inspection – CMM equipment, gauges, and inspection labor to verify conformance
- Management – production scheduling, purchasing, supplier management, and quality system overhead
A realistic fully-loaded cost for a single CNC turning cell – machine, operator, tooling, and overhead – is $100,000 to $150,000 per year before the first part is counted. The question is whether your production volume justifies that investment.
What Contract CNC Machining Actually Costs
Contract machining converts the fixed costs of in-house production into variable costs. You pay per part – and you only pay when you need parts. The contract shop bears the cost of the equipment, operators, tooling, overhead, and quality system. You pay a per-part price that reflects all of those costs allocated across every customer the shop serves.
For a manufacturer sourcing precision turned components through a distributor, there is an additional layer of cost: the distributor’s margin – typically 20% to 40% – added between the machine shop and your dock. Buying direct from a machine shop like Resolute Precision eliminates that margin and gives you the actual machining cost.
The Make vs Buy Framework
Five questions determine which approach makes economic sense for a specific component or family of components:
1. What is the annual volume?
Volume is the primary driver. At very high volumes – hundreds of thousands of parts per year – dedicated in-house production can reach the cost efficiency of a contract shop. At moderate volumes – tens of thousands of parts per year or less – contract machining is almost always more economical because the fixed costs of in-house production are spread across too few parts.
2. How specialized is the required capability?
If your product requires Swiss CNC machining, 5-axis milling, or ID honing – capabilities that require highly specialized equipment and expertise – the investment in in-house capability is rarely justified unless it is your core business. Contract shops that specialize in these capabilities amortize the equipment and expertise cost across many customers.
3. How stable is the design?
In-house machining is most justified for products with stable designs that run continuously. If your design changes frequently, in-house setups and tooling are repeatedly made obsolete – the flexibility of contract machining is more valuable than the control of in-house production during development and early production phases.
4. What is the strategic value of the capability?
Some machining capabilities are genuinely strategic – they are central to your competitive differentiation, and the knowledge built through in-house machining directly improves your product. Medical device manufacturers who machine their own implant components often maintain in-house machining because the knowledge loop between machining and design is part of their competitive advantage.
For most OEM manufacturers whose core business is not machining – fluid power, automotive, industrial machinery – precision machining is a purchased capability, not a strategic one. Outsourcing it to a specialist is a rational decision.
5. What are the capacity utilization implications?
In-house machining capacity is fixed. When demand exceeds capacity, you face a choice between overtime, capital investment, and customer allocation. When demand drops below capacity, you have idle equipment and operators with no production to justify their cost. Contract machining flexes with demand – you order more when you need more, less when you need less.
When Contract CNC Machining Is Clearly the Right Choice
- Your component volume is under 50,000 parts per year across the range of machined parts in your BOM
- The required capability – Swiss CNC, 5-axis milling, ID honing, mill/turn – would require a capital investment you cannot justify on your production volume alone
- Your product is in development or early production and design changes are frequent
- You need breadth – turning, milling, honing, and value-added services – that would require multiple machine types in-house
- You want to convert the fixed costs of machining capacity into variable costs that flex with your demand
When In-House Machining Makes Sense
- Your single-part volumes exceed 500,000 per year with stable demand and design
- Machining capability is genuinely strategic – you have a proprietary process or the machining knowledge directly improves your product
- You are a Tier 1 supplier whose customer requires you to hold specific processes in-house as a qualification requirement
- The geometry of your parts is simple enough that standard equipment and generalist machinists are sufficient
The Hybrid Approach
Many manufacturers use both. In-house machining covers the highest-volume, simplest-geometry parts where dedicated equipment is justified. Contract machining covers the complex, lower-volume, specialized-capability parts where an outside specialist is more economical and more capable.
The key is not a binary in-house vs contract decision – it is a rigorous component-by-component analysis of volume, complexity, capability requirement, and strategic value.
What to Look for in a Contract CNC Machining Partner
If contract machining is the right answer for some or all of your machined components, the quality of the partner matters as much as the decision itself. Look for:
- Direct manufacturer – a shop that makes the parts, not a broker who resells another shop’s work. Direct pricing eliminates distributor markup.
- Breadth of capability – Swiss CNC, multi-axis turning, 5-axis milling, honing, and value-added coordination in one facility reduces the number of supplier relationships you manage
- ISO 9001 certification – an audited quality management system with in-process inspection, traceability, and documentation
- Technical responsiveness – a shop whose engineering team reviews your drawing and tells you honestly whether they can make it, and at what cost
- Inventory programs – blanket orders, JIT delivery, and finished goods stocking that convert procurement overhead into scheduled releases
Summary
Contract CNC machining makes economic sense for most OEM manufacturers whose core business is not machining. The capital, labor, and overhead costs of in-house production are only justified by volumes and strategic considerations that relatively few manufacturers can claim. For everyone else, a capable direct-from-manufacturer contract shop delivers better capability, more flexibility, and lower per-part cost than in-house production.
Have a Part to Quote?
Send us a drawing. We will have a manufacturing feasibility note and real price back to you within 24 hours. No commitment, no pressure – just a straight answer from the people who will run your job. Contact Us or call (260) 665-6463.