In the world of custom manufacturing and prototyping, the decision between DIY injection molding and CNC turning services can significantly impact your product’s cost, speed, quality, and scalability. Both methods are powerful tools in the maker’s and engineer’s toolkit—but they serve different purposes and suit different types of projects.
So how do you know which method is right for your next build? In this guide, we’ll break down the key differences, advantages, and limitations of DIY injection molding machines versus CNC turning services, helping you make an informed decision.
Understanding DIY Injection Molding
Injection molding is a process in which molten material—typically plastic—is injected into a mold cavity to create identical parts. Traditionally used for mass production, injection molding machines have become more accessible to individual makers and small businesses thanks to DIY injection molding machines.
🔧 What is a DIY Injection Molding Machine?
A DIY Injection Molding Machine is a compact, cost-effective version of industrial equipment that enables individuals or small startups to manufacture plastic parts in-house. These machines typically use aluminum molds and are operated manually or semi-automatically.
✅ Pros of DIY Injection Molding
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Low Per-Part Cost: Ideal for large batches after the mold is made.
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Speed: Once set up, you can produce parts rapidly.
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Plastic Focus: Perfect for plastic components like clips, cases, gears, etc.
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Scalability: Good for low- to mid-volume production.
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Compact & Affordable: Especially for hobbyists, prototypers, or startups.
❌ Cons of DIY Injection Molding
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High Initial Effort: Mold creation requires time and precision.
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Limited Material Options: Primarily used for thermoplastics.
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Design Constraints: Undercuts and complex geometries are hard to mold.
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Skill Required: Mold-making and temperature control need experience.
What is CNC Turning?
CNC turning is a subtractive manufacturing process in which a rotating workpiece is shaped by a stationary cutting tool. CNC turning is perfect for cylindrical parts like shafts, bushings, screws, and housings.
Unlike injection molding, CNC turning doesn’t require molds. Instead, a computer-controlled lathe removes material (usually metal or plastic) from a solid rod or bar to achieve the desired shape.
✅ Pros of CNC Turning Services
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No Mold Needed: Faster prototyping and customization.
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High Precision: Excellent dimensional accuracy and surface finish.
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Material Versatility: Works with metals, plastics, and composites.
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Complex Geometry: Threading, internal bores, grooves, tapers, etc.
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Scalable: Great for both one-offs and mid-volume production.
❌ Cons of CNC Turning Services
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Higher Per-Part Cost: Especially for high-volume runs.
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Longer Machining Time: Compared to injection molding for plastics.
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Not Ideal for All Shapes: Works best for round or symmetrical parts.
Comparing the Two Methods: Key Factors
| Feature | DIY Injection Molding Machine | CNC Turning Services |
|---|---|---|
| Setup Cost | Moderate (machine + mold-making tools) | Low for one-offs, higher for batch runs |
| Per-Part Cost | Low (after mold creation) | Moderate to High (depending on complexity) |
| Lead Time | Short after mold is ready | Depends on material and geometry |
| Material Options | Mostly thermoplastics | Wide range: aluminum, steel, brass, plastic, etc. |
| Part Complexity | Limited (simple shapes preferred) | High (can machine complex internal features) |
| Volume Suitability | Best for 100–10,000 parts | Best for 1–1,000 parts |
| Precision | Moderate | Very High |
| Applications | Plastic enclosures, buttons, prototypes | Shafts, nozzles, threaded parts, connectors |
When Should You Choose a DIY Injection Molding Machine?
A DIY injection molding setup is ideal if:
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You frequently produce plastic parts in large quantities.
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Your designs are relatively simple and repeatable.
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You have the skills or support to design and machine molds.
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You’re looking to reduce long-term production costs.
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You’re developing consumer products, cases, plastic housings, or small toys.
It’s a strong choice for small businesses, product developers, and hobbyists who want control over production and cost-per-part efficiency.
👉 Learn more about setting up a DIY Injection Molding Machine here:
🔗 https://cnc-machiningservices.com/diy-injection-molding-machine/
When Should You Use CNC Turning Services?
CNC turning is the better choice if:
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You need parts made from metal or high-performance plastics.
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You’re producing cylindrical or rotational parts with tight tolerances.
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Your project demands flexibility, rapid prototyping, or customization.
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You don’t want to deal with mold creation or long setup times.
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You’re making mechanical components like bushings, rods, threaded shafts, etc.
It’s the go-to method for industries such as aerospace, automotive, robotics, and medical devices.
Hybrid Strategy: Using Both
Interestingly, many successful manufacturers use both methods during the product lifecycle:
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Prototype with CNC turning or milling, then switch to injection molding for full production.
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Combine machined and molded parts in a single product (e.g., plastic casing with metal inserts).
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Use CNC services to make the mold inserts for DIY injection molding setups.
This hybrid approach ensures you balance speed, precision, and cost-effectiveness through every phase of development.
Final Verdict: Which One is Best?
There’s no one-size-fits-all answer. The best process depends on your:
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Material requirements
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Production volume
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Design complexity
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Budget and timeline
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End-use application
🏆 Choose a DIY Injection Molding Machine if:
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Your project involves simple plastic parts in medium to large volumes.
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You’re a maker, startup, or DIY enthusiast ready to build and iterate fast.
🏆 Choose CNC Turning Services if:
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You need metal parts, high precision, or complex geometries.
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You’re producing functional prototypes or specialized components in low volumes.
✅ Need Help Deciding?
Whether you’re designing a plastic product or a mechanical component, having the right technology and guidance can accelerate your success.
💡 Explore CNC machining, mold-making, and custom fabrication support at:
👉 https://cnc-machiningservices.com/diy-injection-molding-machine/
They offer professional insight into both DIY injection molding machines and custom CNC turning, helping you bring ideas to life—faster, smarter, and more affordably.
