Metal 3D Printing (DMLS/SLM)

Metal 3D printing builds fully dense metal parts directly from powder, layer by layer. On OpusFab this process is listed as metal 3D printing and uses DMLS (direct metal laser sintering) or SLM (selective laser melting) machines. The two names describe essentially the same approach: a high-power laser fuses fine metal powder into solid parts. DMLS is more common for alloys like aluminum and stainless steel, SLM for a wider range of metals including titanium, but from a customer’s point of view the quoting and ordering flow is the same.

How it works

1. A thin layer of metal powder is spread over a build plate inside a sealed chamber filled with inert gas.
2. A laser melts the powder in the shape of one cross-section of your part, welding it to the layer below.
3. The plate lowers, fresh powder is spread, and the process repeats until the part is complete.
4. The part is cut from the build plate, support structures are removed, and it usually goes through heat treatment to relieve internal stress.

Because the laser fully melts the powder, the resulting parts are dense and have mechanical properties close to wrought or cast metal.

When metal printing beats CNC

Metal printing is not a cheaper replacement for machining. It wins in specific situations:

• Geometry CNC cannot reach: internal cooling channels, conformal passages that follow the part’s shape, lattices, and organic topology-optimized forms that no cutting tool can access.
• Part consolidation: assemblies of several machined pieces redesigned as one printed part, eliminating fasteners, seals, and joints.
• Very small quantities of complex parts: for one or a few units of a complex geometry, printing avoids machining setups and custom fixturing.
• Rapid iteration on metal parts: when a plastic prototype is not representative and you need real metal quickly.

If your part is a straightforward block, bracket, or turned shape, CNC machining is almost always faster, cheaper, and more accurate. See CNC vs. 3D printing design rules.

Cost and lead time expectations

Metal printing is the most expensive process on the platform per part. Cost is driven by build volume (how much space the part takes in the machine), print time, powder cost, and post-processing. A few guidelines:

• Small, complex parts print economically; large solid parts do not. If most of the volume can be machined from bar stock, machine it.
• Lead times are longer than plastic printing and often longer than simple CNC work, because builds take hours to days and parts need plate removal, support removal, and heat treatment.
• Surface finish as printed is rougher than machined surfaces. Critical faces, bores, and threads are often finish-machined after printing, which adds cost and time.

The instant quote reflects all of this automatically: upload the STEP file, select metal 3D printing, and compare the price and lead time against CNC for the same part. For unusual alloys, large parts, or quantities above the 1 to 100 instant-quote range, request a custom quote.

Design and tolerance notes

Printed metal parts need support structures on steep overhangs, just like plastic printing, and sharp internal corners should be filleted. Tolerances are looser than CNC’s ±0.05mm standard, so plan for finish machining on precision interfaces. The automatic DFM analysis flags potential issues on upload with a “DFM Warning” pill in the quote table. See DFM overview and Tolerances explained.

Check the quote editor for the current live list of printable metals. For a comparison against every other process, see Choosing a process.