Metal additive manufacturing R&D as Metal 3D Print Specialist at Uniformity Labs (SLM Solutions SLM 125 + SLM 280, AlSi10Mg / Ti-6Al-4V / 316 + 304 SS / Inconel 625 + 718), built on a decade of polymer 3D-printing experience starting with smartphone-mount prototyping at Bracketron in 2013.
Inside an SLM Solutions printer mid-build: the laser is selectively melting metal powder layer-by-layer (the bright sparks). The dark circular outline visible in the powder bed is the cross-section of the part currently being built — a flange-style geometry. This image captures what "metal 3D printing" actually is at the working layer: a fiber laser, a few tens of microns of powder, and a carefully-chosen scan pattern.
A documentation repository for my additive-manufacturing practice across two distinct chapters:
- Metal LPBF (Laser Powder Bed Fusion) at Uniformity Labs (Fremont, CA), 2022–2023 — the deepest, most recent thread. As Metal 3D Print Specialist I ran the print floor on SLM Solutions SLM 125 and SLM 280 machines across five alloy families, supporting process-development DoEs that targeted forged-equivalent mechanical properties. This is the bulk of the repo.
- Polymer 3D printing, 2013–present — a decade-plus of practice across filament (FFF/FDM), resin (SLA / DLP / MSLA), and earlier powder bed methodologies, beginning with smartphone-accessory prototyping at Bracketron in 2013.
Sister repositories: tensile-testing (where the AM specimens were characterized to ASTM E8/E8M), cnc (where AM-printed near-net parts were finished to drawing tolerance), metal-powder-flow-device (the powder-flow measurement instrument feeding the powder-recipe DoEs), and tumbler-oven (the powder-conditioning equipment repair story upstream of the build floor).
Taken together, tumbler-oven + metal-powder-flow-device + additive-manufacturing + cnc + tensile-testing form a single Uniformity Labs workflow: powder conditioning -> flow characterization -> LPBF build -> CNC finishing -> mechanical validation.
Metal AM has to compete with forged and wrought mill products on certified mechanical performance for any serious end-use part. Out-of-the-box, an SLM-printed part typically falls 10–30% short of forged-equivalent UTS, with porosity-driven elongation deficits even worse. Closing that gap is a process-development problem: the right combination of powder recipe and laser parameters can drive an AM part close enough to forged that it qualifies for production use.
That gap-closing work was my role.
The SLM Solutions SLM 125 HL — a research-and-prototyping LPBF machine with a 125 × 125 × 125 mm build envelope. Used for material-characterization coupons, small-batch parts, and DoE iterations where build-time-per-experiment matters more than build-volume.
The SLM Solutions SLM 280 — production-class LPBF with a 280 × 280 × 365 mm build envelope. Used for larger parts and DoEs where the geometry needed full-size validation rather than small-coupon proxy.
| Alloy | Class | Why printed |
|---|---|---|
| AlSi10Mg | Aluminum-silicon-magnesium casting alloy | Workhorse aerospace AM material |
| Ti-6Al-4V (Ti64) | Alpha-beta titanium | Critical aerospace + medical-implant grade |
| 316 / 304 stainless steel | Austenitic stainless | Corrosion-resistant, biocompatible |
| Inconel 625 | Nickel-chromium superalloy | High-temperature corrosion + strength |
| Inconel 718 | Nickel-chromium-iron precipitation-hardening superalloy | High strength to ~700 °C |
(Same photo as the hero, here for the equipment-in-use context.) The bright sparks are the laser melting metal powder; the dark circular outline is the part being built layer-by-layer.
A batch of metal-printed rollers on a build plate — fresh off the SLM, still attached to the substrate. The rough sintered surface texture is characteristic of as-printed LPBF parts; critical features will be CNC-finished downstream (see the cnc sister repo).
A printed gyroid lattice cube — the kind of geometry that's trivial in AM and impossible by any other manufacturing method. Lattice structures like this give AM its weight-to-stiffness advantage over solid forgings and are part of why aerospace + medical buy into the process despite the property gap.
A powdered-metal flowability device measures the angle of repose as the finely granulated particles alternate between flowing and sticking to each other. The angle is one of the dominant powder-flowability metrics for LPBF — it directly predicts how cleanly the recoater blade will spread a fresh layer across the build plate. Sister project: the metal-powder-flow-device is the in-house instrument I designed and built that fed quantitative powder-flow data into the same DoE loop, and the downstream porosity story shows up in the tensile-testing coupons.
The process-development work was structured as designs of experiments spanning two orthogonal factor families:
- Powder-recipe DoEs — composition, particle-size distribution, flowability (instrument: the
metal-powder-flow-devicewe built in-house), recycle ratio - Laser-parameter DoEs — power, scan speed, hatch spacing, layer thickness, scan-pattern strategy
Response variables: tensile properties (UTS, 0.2% yield, elongation; full methodology in tensile-testing), part density and porosity (cross-section measurement + Archimedes), fracture-surface morphology, and dimensional accuracy.
The objective every DoE iteration was the same: maximum density, lowest porosity, properties as close to forged equivalents as possible.
Specific DoE designs, factor levels, response data, and process parameters are proprietary to Uniformity Labs and are not in this repository.
Every AM-printed part with critical tolerances passed through the CNC floor next. The parts in the bracket/roller batch above each had bores, mounting faces, and threaded features that the LPBF process couldn't hit to drawing — those got finished on the Haas ST-20Y or VF-2. Full operator-side narrative in cnc.
Long before metal LPBF, I was 3D-printing in polymer. The thread starts at Bracketron in 2013, prototyping smartphone-mount accessories — dashboard mounts, windshield mounts, cup-holder mounts, vent mounts, the family of accessories that fed the suction-cup-mount patent work and the broader Bracketron product line. Plastic prototypes off a desktop FFF machine, iterated daily, were how the geometry got proved out before tooling commitments.
Across the decade I've worked across all three major polymer methodologies:
- FFF / FDM (filament) — the most-used. Prototype iteration, fixturing, jig stock, custom tooling. Material range: PLA, ABS, PETG, TPU, nylon, carbon-fiber composites.
- Resin (SLA / DLP / MSLA) — small-feature prototypes, lost-resin investment-casting masters, smooth-surface visual prototypes.
- Powder-bed polymer (SLS-adjacent) — early exposure that turned out to be the conceptual on-ramp for the metal LPBF work years later.
This polymer history is why the jump to metal LPBF at Uniformity Labs was a methodology shift rather than a complete unknown — the print parameters change but the material-meets-process-meets-geometry mental model carries across.
additive-manufacturing/
├── README.md ← you are here
├── LICENSE ← CC-BY 4.0 (scoped to original content only)
└── images/ ← SLM equipment shots, in-process LPBF imagery,
build plates, work products, failure modes
| Section | Status |
|---|---|
| Repo description, license | ✓ done |
| Equipment + process narrative (Metal LPBF) | ✓ done |
| Polymer 3D-printing history | ✓ done |
| Equipment + work-product photos | ✓ done |
| Public-domain process-parameter references | forthcoming |
| Cross-repo skill files | forthcoming (planned: additive-manufacturing-doe, lattice-design-for-am) |
Released under CC-BY 4.0 — original written content and photographs in this repository are mine, free to reuse and adapt with credit. The underlying SLM process parameters, DoE designs, and proprietary AM data developed at Uniformity Labs and Bracketron remain the property of those employers. This license does not apply to those proprietary methods or data — none of which are included here.