It's the question we get before almost every job: should this part be 3D printed or CNC machined? People often assume one is simply the "better" technology — but they're built for opposite problems, and picking the wrong one means paying too much, waiting too long, or ending up with a part that doesn't hold up. Both live side by side in what we do, so we choose per part, not per preference.

The good news is the decision usually comes down to four things you already know about your part: how tight the tolerances are, what it's made of, how complex the shape is, and how many you need. Below is the plain version of how those factors point to one process or the other — and when the smart move is to use both. If you'd rather just send us the drawing, we'll make the call, but here's how it works.

01Two opposite approaches

The core difference is right there in the categories: one is subtractive, one is additive. CNC starts with a solid block and cuts material away; 3D printing starts with nothing and builds the part up layer by layer. That single distinction drives almost every trade-off that follows.

Read those two columns and most jobs sort themselves quickly. A precision metal shaft is a CNC part; a hollow, organically curved housing with internal channels is a printing part. The interesting cases are the ones in between — which is where tolerance and material settle it.

02The tolerance & material gap

This is where the numbers matter. CNC machining is still the accuracy benchmark, but the common printing processes each land in a different place — and "good enough" depends entirely on the part.

On material, the split is just as clean. CNC handles aluminium, steel, and titanium as everyday work; printing shines in engineering plastics and complex geometry, with metal printing reserved for shapes no cutter could ever reach.

The question is rarely "which is better." It's "which one is this part asking for."

03Which one your part needs

Here's the fastest way to decide. Run your part against both lists — whichever side it ticks more boxes on is almost always the right process.

04Why "both" is often the real answer

The two processes aren't rivals so much as teammates, and some of the best results come from combining them. A common pattern is to 3D-print a complex prototype to validate the design, then CNC-machine the production version — or machine the critical mating faces of a printed part to bring just those surfaces into tolerance.

It runs the other way too: machinists routinely 3D-print the jigs and fixtures that hold parts during cutting, cutting days off setup. Because we run both under one roof, we can mix them on a single job instead of forcing your part to fit one method.

Frequently asked questions

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Is CNC machining more accurate than 3D printing?

Generally, yes. CNC machining holds tolerances around ±0.025mm, while FDM printing sits nearer 0.2–0.5mm and SLA around 0.1mm. For tight-tolerance work CNC still leads, though resin and powder printing close the gap on small, detailed parts.

Can 3D printing make metal parts?

Yes, through metal processes like DMLS and SLM. But for most metal parts CNC machining is faster, cheaper, and stronger — metal printing earns its place mainly when the geometry is too complex to machine, such as internal channels or lattices.

Which is cheaper, 3D printing or CNC?

It depends on the part. For one-off prototypes and complex shapes, 3D printing is usually cheaper and faster because there's no tooling or fixturing. For simple metal parts or larger runs, CNC often wins on cost per finished part.

Which makes stronger parts?

Machined metal is typically the strongest. Printed parts can be strong, but they're limited by layer bonding and available materials — SLS nylon and printed metals are the main exceptions where printed strength holds up well.

When should I use both processes?

Often. A common approach is to 3D-print a complex prototype, then CNC-machine the critical mating faces to tolerance — or machine the main part and 3D-print the jigs and fixtures around it. The two processes complement each other.

How do I decide which process my part needs?

Start from four things: tolerance, material, geometry, and volume. Send us the drawing or the part and we'll tell you whether it's a CNC job, a print job, or a mix of both.