3D printed vs CNC

3D printed grinder vsCNC-machined — compared honestly.

3D printing is brilliant for prototyping. CNC machining is what you choose when the grinder needs to earn repeat impressions for years. Here's an honest comparison — so you pick the right method for your project.

Side by side

Aspect

3D printed

CNC-machined

Material

PLA, ABS or PETG plastic — extruded layer by layer

6061 aircraft-grade aluminium — milled from solid billet

Durability

Good for prototyping; PLA softens at ~60°C, layers can delaminate with heavy use

Decades of daily use; metal doesn't warp, crack or wear thin

Teeth

Moulded geometry — sharp enough initially, but plastic dulls and chips faster

Diamond-cut, CNC-milled teeth that shear cleanly and stay sharp for years

Finish quality

Visible layer lines; post-processing needed for smooth surfaces

Machined tolerances to hundredths of a millimetre; anodized colour baked into the metal

Engraving depth

Surface-level print or shallow etch — the mark sits on top

3D metal engraving cut into the aluminium, finished in gold, silver, black or rose gold

Per-unit cost (volume)

Cheap at very low volume — no tooling, no setup

Higher per-unit at one piece ($25–$75), but tiered pricing hits $6.75 at 1,000

When 3D printing wins

  • You need 1–5 prototype units to test a design before committing to metal
  • Budget is the only constraint and durability doesn't matter
  • The grinder is a one-off event giveaway with a short use window

When CNC wins

  • The grinder is retail merch, a collector piece, or a brand flagship product
  • Daily use over years, not weeks, is the expectation
  • Your logo needs to read as premium — 3D metal engraving, not a surface print
  • You're ordering 25+ units — tiered pricing closes the gap fast
  • You need colour accuracy, tight tolerances, and a flawless finish

The honest bottom line

If you're testing a design idea and need five units tomorrow, 3D printing is the right call. But if the grinder is going to carry your brand name into people's homes for years — you want metal. CNC-machined aluminium with 3D metal engraving is the difference between merch that gets used and merch that gets filed away. GMI does both paths: prototype-friendly small runs with no minimum, and production runs at tiered pricing that drops to $6.75 per unit at volume.

See the difference in a free proof

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