From PO to first article: how a contract manufacturing program actually runs

Between a purchase order and first articles, a contract manufacturer runs a fixed sequence: contract review, DFM feedback, material procurement, process routing in the ERP, fixtures and programs, a first article build and inspection, customer approval, production release, and packout. For a sheet metal assembly that sequence typically takes three to twelve weeks, and most of the schedule risk sits at the two ends — DFM questions and customer approval.

What actually happens between PO and first article?

Buyers see two events: the PO goes out, and a box arrives with first articles and an inspection report. Between those events the manufacturer runs nine stages, and each one has a specific owner, a specific input, and a specific way it can stall.

The reason to understand the sequence is not curiosity. Program dates slip at predictable points — an unanswered DFM question, a mill-order material, a print revision that changed after the quote, an inspection report sitting in an inbox — and a buyer who knows where those points are can pull the date in without paying for a rush. This article walks the sequence as it runs at Nevatronix and at most disciplined contract manufacturers; the durations are typical industry ranges, not our quote for any specific job.

The nine stages and how long each typically takes

Stage	What happens	Typical duration (industry ranges, not our quote)
1. Contract review	PO compared line by line to the quote: revision, quantity, price, delivery, terms, documentation	1–3 business days
2. DFM feedback	Engineering reviews the drawings for manufacturability and sends questions or suggested changes	2–5 business days; longer if a redesign is needed
3. Material procurement	Stock pulled or ordered; certifications requested	1–3 days for stocked gauges; 2–6 weeks for mill orders or specialty alloys
4. Process routing in the ERP	Job entered with operations, work centers, and inspection points; traveler generated	1–2 business days
5. Fixtures and programs	Cutting nests, bend programs, weld fixtures, hardware and finish setups built	3–10 business days
6. First article build	1–5 units run through every routed operation	1–2 weeks for an assembly; days for a piece part
7. First article inspection	Dimensional report against the print; material and finish certs assembled	1–3 business days
8. Customer approval	Buyer reviews the report and physical units	Set by the customer; 1–10 business days is common
9. Production release and packout	Job released, run built, serialized where required, packed to spec	Release same day to one week after approval; packout 1–3 days

Read down the right-hand column and the pattern is obvious: the shop-controlled stages are days, and the two stages that routinely run to weeks — material and customer approval — are the ones a buyer can influence before the PO is even placed.

Contract review and DFM: where the schedule is decided

Contract review is the unglamorous step that prevents most disputes. The order-entry team compares the PO against the quote it was based on: part numbers, drawing revisions, quantities, unit prices, delivery date, Incoterms, payment terms, packaging, and any documentation requirements. ISO 9001:2015 requires this review, and a shop that runs a real quality system will not enter an order until every line matches or the mismatch is resolved in writing. The most common catch is revision drift — the PO cites revision C, the quote was built on revision B, and revision C added a hardware callout nobody priced. (What the ISO certificate does and does not tell you about this discipline is covered in what ISO 9001:2015 actually covers.)

DFM feedback is where engineering looks at the part as a thing to be made rather than a thing to be drawn. On a sheet metal assembly the review covers flange lengths against the brake tooling, hole-to-bend distances, weld access, hardware clearances, finish masking, and whether the flat pattern nests efficiently on the sheet. Some findings are “must change” — a feature that cannot be formed — and some are “would save you money,” such as a tolerance that could relax without affecting fit. Good DFM feedback arrives as a marked-up print with each item flagged by category so the customer can accept or decline in one pass.

This is the first stall point. A DFM question that sits unanswered for a week pushes every downstream stage by a week, and the shop cannot cut material or build fixtures against a print it expects to change. The single most effective thing a buyer can do for the schedule is to name the engineer who will answer DFM questions before the PO goes out.

Material, routing, and programs: the invisible middle

Material procurement is the second stall point and the one most often underestimated. Common gauges of cold-rolled, galvanized, aluminum, and stainless sheet are stocked or available from a service center within days. Plate above about 10 mm (0.375 in), unusual alloys, pre-painted stock, and anything requiring a specific mill certification or heat lot can run to weeks. A buyer who specifies a material for an appearance reason that a stocked equivalent would satisfy is paying for that lead time without knowing it — the DFM stage is where to ask.

Process routing in the ERP turns the drawing into a traveler: an ordered list of operations, each assigned to a work center, with inspection points inserted where the quality plan calls for them. For a typical enclosure the routing might read laser cut, deburr, form, hardware insertion, weld, grind, powder coat, assemble, final inspect, pack. The routing is what lets the shop schedule capacity, and it is what the traceability system hangs off — material lot, operator, and inspection record are all recorded against routing steps. At Nevatronix this runs in MIE Trak Pro; the specific ERP matters less than whether the shop uses one at all.

Fixtures and programs are the part-specific setup. Cutting nests are programmed for the flat pattern; bend sequences are programmed and proven on the press brake; weld fixtures are built where the assembly needs parts held at position while welded; hardware insertion and finish masking are set up. On a sheet metal assembly this is almost entirely soft tooling — programs and modest fixtures — which is why the stage is days rather than the weeks a casting or molding program would spend on hard tooling. The cutting stage itself is explained on the laser site’s flat-sheet laser cutting page; the parent-site view is simply that this stage is fast and its cost is small.

First article build, inspection, and approval

The first article build runs one to five units through every routed operation exactly as production will run them — same material, same programs, same fixtures, same finish. The point is not to make a nice sample; it is to prove the process. A first article built by hand on a bench proves nothing about what unit 300 will look like.

First article inspection measures the result against the print. A proper report lists every dimension on the drawing with its nominal, its tolerance, the measured value, and pass or fail, and it comes with the material certifications for the lots used and finish certifications where specified. Many non-aerospace shops lay the report out in the aerospace FAI form format, which non-aerospace customers borrow because it is familiar and complete. Automotive-derived programs sometimes ask for a PPAP-style package instead; the content overlaps heavily. What matters is that every dimension is measured and every nonconformance is either dispositioned or sent back to you with a proposed fix, not quietly accepted.

Customer approval is the third stall point, and it is entirely on the buyer’s side of the table. The report and the physical units arrive; someone with authority has to review them and say yes. Programs miss dates here more often than at any shop-controlled stage, simply because the reviewing engineer is busy. Two habits shorten it: agree before the PO on who approves and how many days they have, and ask the shop to send the inspection report electronically the day it is complete rather than waiting for the units to ship.

Production release follows approval. Material for the run was ideally ordered in parallel with the FAI, so release can start within days. Packout closes the loop: units packed to the specification on the PO, serialized and labeled where the program requires it, shipped or held in Kanban stock. For assemblies, the shop’s assembly and packout capability is where the program either scales or does not — the sheet metal site’s assembly service page describes how that stage runs at unit rates a program can plan around.

Where this breaks down

The sequence assumes a stable drawing, a responsive customer, and a shop with a real quality system. Remove any one and the durations stop meaning much.

• Revision mid-program. A print change after material is cut or fixtures are built restarts stages 3 through 7 for the affected features. Disciplined shops re-quote and re-baseline the date rather than absorbing the change silently, which is the right behavior even when it is inconvenient.
• Material you cannot substitute. If the specification genuinely requires a mill-order alloy or a specific coated stock, the six-week material line dominates everything and no amount of shop speed recovers it. Order long-lead material against a letter of intent if the program cannot wait for the PO.
• Approval without a named approver. An inspection report addressed to a general inbox waits. Name the person.
• Certification requirements the shop does not hold. If the program requires AS9100, ISO 13485, or ITAR registration, the sequence above still applies but Nevatronix is not the shop — we hold ISO 9001:2015 and run a UL listed shop, and we do not take flight hardware, regulated medical device, or ITAR work.
• Volume outside the process. Below one unit the sequence is a prototype, and above roughly 50,000 units of a frozen design the economics may favor hard tooling the sequence does not include.

What to put on the PO

The PO is the input to contract review, so anything missing from it is a question that costs a day. A complete PO for a sheet metal assembly carries the drawing number and revision for every part, the quote number it is based on, quantity and delivery date, the material and finish callouts or a pointer to the print that has them, the inspection and documentation deliverables (FAI report, material certs, finish certs, serialization), packaging requirements, and the name of the engineer who will answer DFM questions and approve the first article. If the program will run as Kanban or scheduled releases, say so on the first PO rather than after the first shipment. The qualification steps that precede the PO — capability review, pilot order, second-source planning — are covered in how OEMs qualify a second-source metal fabricator; the capabilities page lists what to check us against.

How we’d quote your program

Send the drawings, the target quantity and schedule, and the documentation you expect with the first article to our contact page. We will return DFM notes with the quote so the first stall point is cleared before the PO exists, and we will tell you plainly if any requirement sits outside what we do.

References

1. NIST Manufacturing Extension Partnership — supplier and manufacturing process resources
2. SAE AS9102C — Aerospace first article inspection requirement (the FAI form format non-aerospace shops borrow)
3. AIAG — Production Part Approval Process (PPAP) and automotive core tools
4. ASME Y14.5 — Dimensioning and tolerancing
5. AWS D1.1 — Structural welding code, steel