Why the Workflow Matters As Much As the Machine
The difference between a print shop and a manufacturing partner is what happens before and after the print. A print shop takes your STL, queues it, ships it. A manufacturing partner reviews the geometry against the application, flags problems before they become scrapped parts, selects material based on load cases and environment, and ships with documentation that connects the delivered hardware to a traceable production record.
When you send an STL without context, critical information gets lost: which surfaces are load-bearing, what the operating temperature ceiling is, whether a GD&T callout on the drawing is achievable with the selected process, what happens downstream if a critical feature is three-tenths out of tolerance. Recovering that information after a bad part arrives costs more time than a 30-minute review before the job runs.
The Builders Generation workflow runs seven steps for every production job — not as overhead, but because each step prevents a specific class of failure downstream.
Step 1: The Brief
Before anything goes on a machine, we need the full application picture. The geometry file is necessary but not sufficient.
What we need from you:
- Geometry — STEP or native CAD file preferred, plus a drawing with GD&T callouts for all critical dimensions
- Load cases — primary load magnitude and direction, secondary loads, shock and vibration exposure, thermal cycling range
- Operating environment — sustained temperature range, chemical exposure, UV exposure, moisture and humidity
- Timeline and quantity — single prototype, bridge production, or recurring production run
- Certification requirements — none, CoC only, AS9100 production record, FAR 25.853, NASA ASTM E595, or program-specific equivalents
The brief takes 20–30 minutes to complete properly. It eliminates the two most common failure modes: wrong material for the application, and geometry that cannot be built to the tolerances called out on the drawing.
Step 2: DfAM Review
Design for Additive Manufacturing review happens before a single parameter is loaded.
What we check:
- Build orientation — where do the layer interfaces fall relative to the primary load paths? Z-direction inter-layer bond strength is 30–40% lower than XY-plane strength in most high-performance polymers. Critical tensile paths must run in XY.
- Wall thickness — minimum feature sizes are material-specific. PEEK and ULTEM require minimum walls of 0.8–1.0 mm. CF-filled materials have minimum wall constraints driven by fibre length and flow behaviour.
- Support strategy — which surfaces require support, how is support accessed for removal, and what is the surface quality requirement on support-contact faces? Mating surfaces and sealing faces cannot tolerate support witness marks.
- Interface geometry — mating features, press fits, and clearance fits must be reviewed against the process capability of the selected material.
- Material compatibility — some geometries cannot be built in the required material without redesign.
Red flags we flag before running:
- Unsupported overhangs beyond printability limits (>45° from vertical without support in semi-crystalline polymers)
- Wall thicknesses below material-specific minimums — PEEK below 0.8 mm, PA-CF below 0.6 mm
- GD&T callouts tighter than process capability: ±0.1 mm on PEEK is achievable post-anneal; ±0.05 mm requires secondary machining
Step 3: Material Selection
| Primary Driver | Recommended Material | Notes |
|---|---|---|
| Temperature > 200 °C sustained | PEEK, CF-PEEK | Semi-crystalline; requires chamber printing |
| Temperature 150–200 °C | ULTEM 9085, ULTEM 1010, PPS-CF | ULTEM for FAR 25.853; PPS-CF for chemical exposure |
| Temperature 120–150 °C | PC-CF, CF-PEEK | PC-CF for impact; CF-PEEK for stiffness |
| Temperature < 120 °C | PA-CF, ASA | PA-CF for structural; ASA for UV exposure |
| Chemical exposure (fuels, solvents) | PPS-CF | Highest chemical resistance in FFF portfolio |
| Weight-critical, stiffness-driven | CF-PEEK, PA-CF | CF-PEEK specific stiffness approaches aluminium |
| FAR 25.853 (cabin flammability) | ULTEM 9085 | Certified without additional treatment |
| Space outgassing (ASTM E595) | CF-PEEK, PPS-CF | TML < 0.5%, CVCM < 0.02% without bakeout |
| Impact at sub-zero temperatures | PC-CF | Ductile to -40 °C |
Step 4: Print
Print parameters for each material are locked in our process records, not adjusted run-to-run.
PEEK runs at 430 °C nozzle, 165 °C bed, 175 °C chamber. These are not starting points — they are production settings validated against coupon test data. Semi-crystalline polymers require sustained elevated chamber temperatures throughout the build to control crystallisation rate. Chamber temperature deviation causes residual stress, warping, and reduced mechanical properties.
Every spool used in a production run is logged by manufacturer lot number. The lot number ships with the job documentation. If a material recall occurs, we can identify every part produced from that lot.
Step 5: Post-Print Processing
Parts do not go from printer to shipping box.
Support removal quality directly determines surface quality on mating and sealing features. Support witness marks on critical surfaces are treated as a non-conformance.
Annealing protocol for semi-crystalline polymers: PEEK and ULTEM parts undergo a controlled anneal cycle to complete crystallisation and relieve internal stresses. PEEK protocol: ramp to 200 °C at 2 °C/min, soak 2 hours, ramp down at 1 °C/min. ULTEM 9085 anneals at 175 °C for 2 hours on the same ramp profile. Forced-air fast cooling is not used — it reintroduces thermal stress.
Expected dimensional change post-anneal: < 0.3% linear for PEEK, < 0.2% for ULTEM 9085.
Step 6: Dimensional Inspection
Every production part is inspected against the critical dimensions called out on the customer's drawing.
Results are recorded in a dimensional inspection report with nominal dimension, measured value, tolerance, and pass/fail for each feature. A feature that fails its callout triggers quarantine of the part. We do not ship out-of-tolerance parts and report them as passed.
Step 7: Documentation Package
The documentation package ships with every production run — not as an optional add-on.
Standard documentation for every job:
- Certificate of Conformance (CoC) — certifies that parts were manufactured per the specified process and conform to drawing dimensions within stated tolerances
- Dimensional Inspection Report — feature-by-feature measured vs. nominal table
- Process Parameter Record — locked print settings, machine identifier, chamber temperature log, date of manufacture
- Material Lot Traceability — material manufacturer, grade designation, lot number, receipt date
For aerospace and defence programs: FAI per AS9102, material certifications from raw material manufacturer, non-conformance records.
Turnaround Times by Material Tier
| Material Tier | Typical Turnaround | Documentation |
|---|---|---|
| Standard (ASA, ABS, PC) | 3–5 business days | CoC, Dimensional Report |
| Engineering (PA-CF, PC-CF) | 5–7 business days | CoC, Dimensional Report, Process Record |
| High-Performance (ULTEM, PPS-CF) | 7–10 business days | Full package including lot traceability |
| Premium (PEEK, CF-PEEK) | 10–14 business days | Full package + qualification documentation |
What Makes This Different From a Print-on-Demand Shop
DfAM review is included, not billed separately. Problems found before the machine runs cost 30 minutes. Problems found after shipment cost a revision cycle.
Material parameters are locked, not variable. A PEEK job run today uses the same parameters as a PEEK job run six months ago.
Documentation is standard, not an add-on. Every job ships with a CoC and dimensional inspection report. The infrastructure already exists for programs that need more.
We will turn away jobs where the material or process is wrong for the application. If a geometry cannot be built to the tolerances on the drawing in the requested material, we say so at the DfAM review stage rather than printing a part that will fail incoming inspection.
The build is the smallest part of the job. The brief, the review, the inspection, and the documentation are what determine whether the hardware deploys and stays deployed. That is the work we do on every production run at Builders Generation.
