What is 3D Printing?

Quick Answer

3D printing, or additive manufacturing, creates physical objects by building up material layer by layer from a digital 3D model. Unlike traditional subtractive manufacturing, 3D printing adds material only where needed, enabling complex internal geometries, rapid design iteration, and cost-effective low-volume production.

How 3D Printing Works

The process starts with a 3D CAD model, which is sliced into hundreds or thousands of horizontal layers by slicing software. The 3D printer then deposits or solidifies material one layer at a time, building the part from bottom to top. Common 3D printing technologies include FDM (fused deposition modeling), SLA (stereolithography), SLS (selective laser sintering), and MJF (multi jet fusion).

Key Advantages

Design Freedom: Create complex geometries, internal channels, lattice structures, and organic shapes impossible with machining. Speed: Go from design to physical part in hours, not weeks. No Tooling: Eliminate mold and fixture costs, ideal for prototyping and low-volume production. Material Efficiency: Minimal waste compared to subtractive manufacturing. Customization: Each part can be unique without cost penalties.

When to Use 3D Printing

3D printing is ideal for: Prototypes and design verification; Low-volume production under 500 units; Complex geometries that cannot be machined; Custom medical and dental applications; Tooling and fixtures; Spare parts and reverse engineering. For high-volume production, CNC machining or injection molding typically offer better economics.

Why Choose SOMI Custom Parts

SOMI Custom Parts offers both 3D printing and CNC machining services, giving you the best of both worlds. Our engineering team helps you determine the optimal manufacturing strategy for each project. For prototypes, we often recommend 3D printing for speed, then transition to CNC machining for production, ensuring you get the right process at every stage of development.

Case Study

An industrial equipment manufacturer needed to verify the fit of a new hydraulic manifold design before committing to CNC production. SOMI 3D printed the manifold using SLS nylon in 24 hours. The prototype revealed two interference issues that were corrected before CNC production, saving $8,000 in potential rework costs and 2 weeks of schedule delay.

Industry Data

The additive manufacturing industry has grown at a compound annual rate of 21% over the past decade (Wohlers Report, 2025). 3D printing is now used by 97% of Fortune 500 manufacturing companies in some capacity, with prototyping remaining the most common application at 78% of users.

Related Questions

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