Services / Production management

Production managed from PO to shipment.

Once the tool is cut the work changes: releasing materials, approving the first article, running the pre-production and pilot batches, writing the inspection plan the line works to, and closing the documents that release the balance. Ideambox runs that phase with production partners we have worked with for over 15 years, in injection moulding and PCB manufacturing among others.

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Assembled PCBA on an inspection bench during production

Electronics: the first article decides the run

A reflow profile is cheapest to correct on the first board off the line. We specify what the SMT first article has to prove before the reels are consumed — AOI, X-ray on every BGA, and the firmware's manufacturing test mode running on every board at end of line, inside 30 seconds — and we read that report before the batch continues. Tombstoning, solder bridges and cold joints are profile and stencil problems. They get fixed in the process, not at the rework bench.

Who runs the inspection, and who writes it

IQC on incoming material, IPQC during assembly, FQC on finished units — those checkpoints belong to the factory's own quality department, on their floor, with their disposition authority. Ideambox writes the plan they run against: scope and frequency per checkpoint, AQL per defect class, the photographed defect catalogue, the disposition rules, and the records each stage has to leave behind. Then we audit the plan against what the line actually produces.

Materials released before the first shot

Production starts when the BOM revision is locked to the spec revision and every incoming lot can be traced: certificate of conformance with the manufacturer's date and lot codes, authorised-distributor sourcing on the part types counterfeiters favour, and the second source already named on the AVL rather than qualified in a panic. Critical single-source components carry four to eight weeks of safety stock, and the material for week one is ordered eight to twelve weeks ahead of it.

Partners, not a plant of our own

Ideambox does not own the lines. Production runs through partners we have worked with for over 15 years, in injection moulding and PCB manufacturing among others, with an electronics engineering partner under a standing agreement for board-level questions during the run and a Taiwan sourcing partner we work with regularly. What we bring to their floor is the engineering: a tolerance stack, a tooling review, a line failure read as a process problem.

Build stages

Six batches between first shot and steady state.

Each batch answers a different question, and each has its size for a reason. Jumping from off-tool samples to a five-thousand-unit run is how a fixture problem becomes five thousand units of rework. Quantities follow the ramp-up reference, IDB-RMP-021.

Engineering sample

5–10 units. Process feasibility on the process the factory actually intends to use, not on a sample-room substitute.

Pre-production sample

20–50 units. Full process verification in production materials. Defects come back numbered, measured and photographed at 1:1 against the lighting the plan names — not as an email saying the finish looks wrong.

Off-tool sample, T1

First parts from production tooling, one to two weeks after the tool, then T2 and T3 iterations. The golden sample is signed and dated here by both sides: one copy stays on the production floor, one stays with the buyer.

Pre-production run

100–500 units. This is the batch that sets the yield and cycle-time baseline. Every capacity number after it is calculated from here, so it runs on the production line at production takt or it proves nothing.

Pilot production

500–2,000 units. Validates the fixtures and trains the operators. First-week operators work at 40–60% of an experienced operator and reach 90% at two to three weeks, so a ramp planned on first-week operators is a ramp planned on the wrong number.

Ramp to steady state

2,000–5,000 for the first commercial batch, then 5,000 and up per week. Capacity is planned from stations, shifts, reject rate and an OEE of 0.75–0.90, against a takt each station has to hold: 50 units an hour is a 72-second takt.

Inspection plan

AQL is a number in the contract before it is a number on a report.

Sampling follows ISO 2859-1 level II, normal inspection — the same tables as ANSI/ASQ Z1.4. Sample size comes from lot size, not from the defect rate: a 501–1,200 unit lot draws 80 pieces, a 1,201–3,200 lot draws 125. The accept and reject numbers come from the AQL per class: 0% critical, 2.5% major, 4.0% minor, tightened to 1.0% major where the market demands it.

What counts as critical is written before the run rather than argued after it — a safety hazard, a unit that does not perform its primary function, a missing or wrong regulatory mark, and any component that deviates from the approved BOM even when it works. On PCBA the important checkpoints sit outside the sampling tables: AOI, X-ray on BGA, and the manufacturing test mode on every board.

Scope, frequency and accept criteria per checkpoint
Defect catalogue with class, limit and a photo at scale
Disposition rules: accept, rework, hold, scrap
Calibrated equipment, with the calibration dates
Records per lot: ID, date, inspector, defects, disposition

Hardware product units on the assembly line during a production run

Pilot to mass production

The gate is a list, not a feeling.

Before the line goes from hundreds a week to thousands, the pilot clears a written gate. Short of any of these lines it is not a mass-production line yet, whatever the schedule says.

First-pass yield ≥ 90% on the pilot run
Cpk ≥ 1.33 on every critical dimension, demonstrated by the supplier
SOP at every station, operators qualified against it
Fixtures validated — same fixture, same defects, batch after batch
BOM and spec revisions locked at the production version
Rework path defined for each defect type

A gate can be cleared below 90% first-pass yield when the defects are recoverable at a rework station with a known fix time, the yield-improvement plan is in writing with dates, and the higher unit cost during the ramp is accepted in writing. A deliberate exception, not a default.

Escalation triggers we write into the plan

First-pass yield below 75% — the line has stopped improving on its own. The cause is process, not practice.
One defect type above half of all defects — a single root cause is holding the yield down, and a single root cause is findable.
Under two weeks of a critical component — the shortage lands before the reorder does.
Tooling damage needing repair — dimensions drift before anyone reads a report about them.
Any compliance-relevant defect — a mis-marked or mis-labelled unit is a critical defect, not a cosmetic one.

Corrective action

What happens when a lot fails.

A rejected lot is a document before it is an argument. The sequence is written into the plan in advance, so none of it is negotiated on the day it triggers.

Contain

The lot is held and the defect logged against the catalogue: class, location, measurement, photograph at 1:1 under the lighting the plan names. A defect described only in prose cannot be adjudicated or fixed.

Trace

Serial to build date and lot, lot to BOM revision, revision to the component lots in that batch. Without that chain a failure has no root cause and a containment has no boundary.

Tighten

Two rejected lots in five switch sampling from normal to tightened. Five rejected lots suspend production. Five consecutive passes return it to normal. The switching rule belongs in the plan, not in the conversation after the reject.

Root cause

A reflow profile, a stencil aperture, a worn mould, a torque setting, a feeder, an insertion path. Named with evidence, and not "operator error" as a first answer.

Change

An ECN carries the impact analysis across cost, lead time, regulatory and firmware, the approval, the disposition of the stock on hand, and the effective date the line cuts in on. A change with no effective date is a change nobody applied.

Verify

The first batch after cut-in is inspected against the new revision, and the lever the change was meant to pull is checked against its own timescale: fixture refinement two to three weeks, tooling refinement four to eight, a design change six to twelve.

Release documents

The paperwork that releases the balance.

Production ends in documents. These are the ones that decide whether a shipment is accepted, and they are written during the run, not assembled after it.

Golden sample

A physical unit signed and dated by both sides, photographed at high resolution with a dimensional report, tagged with revision and date. One copy stays on the production floor, one stays with the buyer. Production quality is measured against it rather than against the prototype, the render, or anyone's recollection, and disputes are settled by inspecting it.

Pre-shipment inspection report

The PSI runs on the packed goods against the AQL in the plan: sample size from ISO 2859 level II normal, defect rate, measurements, photographs, and a pass, hold or fail. It exists for the buyer, not for the factory, and the agreement ties the balance to it. Above 1% major defects, the contract puts the re-inspection and the rework on the supplier's side.

Per-lot records

Lot ID, date, inspector, defects and disposition. A first-article report at the start of each shift, a defect log per station and per shift, and the capability data the supplier trends on the critical dimensions. A number that lives only on a whiteboard is not a record.

One revision across the file

The QC plan, the spec sheet and the BOM share a revision number, and the change log names the ECN behind each line. A QC plan that was not updated when the spec changed is worse than no QC plan. The file is retained for the regulatory period — ten years for CE.

The engineering behind the service.

IDB-QCI-004

Quality control & inspection

AQL sampling (ISO 2859), inspection points (IQC/IPQC/FQC/PSI), defect catalogues, the golden-sample workflow, and process-specific defect tables for moulding, PCBA and sheet metal.

PDF reference → IDB-RMP-021

Production ramp-up

Pilot-to-MP gate criteria, yield ramp targets, operator training and line balance, capacity planning for the first 8–12 weeks.

PDF reference → IDB-BOM-005

BOM & component sourcing

BoM structure, component lifecycle, second-source planning, MOQ management, counterfeit risk, ECN workflow. Includes XLSX BoM template.

PDF + XLSX → IDB-RFQ-007

Supplier RFQ checklist

RFQ package contents, supplier qualification, tooling cost benchmarks, and the contract clauses that decide tooling ownership and disputes. Includes XLSX comparison template.

PDF + XLSX → IDB-IMP-008

Importing from Asia

Five-stage reference from specification to landed-in-market: supplier verification, sample rounds, agreement and QA, pre-shipment inspection, shipping and customs.

PDF reference → IDB-SBC-011

Sourcing beyond China

Vietnam, India, Thailand, Taiwan — capabilities, lead times and MOQs by country, Section 301 impact, and how to audit BoM origin rather than assembly origin.

PDF reference →

How an engagement is scoped

There is no standard package and no rate card, because the shape of the work changes with the product. What is released, how many suppliers a build needs, whether tooling exists, the first production quantity and the date it has to hit all move the scope, and they move it a long way. Scope and commercial terms are agreed per project, in writing, before anything starts.

Send the drawing package, the BOM if there is one, the quantity and the date. That is enough to come back with what the work involves.

About to release a PO, or already in a ramp?

The inspection plan is cheapest to write before the PO and most expensive to write after the first rejected lot.

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