Case study · MY · Electronics
Electronics-Assembly Plant
First-pass yield 94.1% → 98.6% · unplanned downtime down 38%
The results
Near-misses logged in seconds from the line, in three languages, so they get reported instead of remembered.
The reflow A3 and shift-start ESD checks moved first-pass yield for the first time in two years.
Fewer line stops and fewer rebuilds pushed on-time delivery to European customers from 91% to 97%.
Finance-verified ledger: board scrap, overtime and expedited freight are the top three lines.
One board instead of a slide, so the meeting is about today and ends on time.
“We argued about the reflow oven for a year. The A3 settled it in three weeks, and now the morning brief tells me which machine to visit before I have had coffee.”
The starting point
The plant builds controller boards and finished units for industrial automation customers in Europe and Japan. Six SMT lines run three shifts, and each shift handed over through a printed slide and a WhatsApp group. By the time the morning tier meeting started, the numbers on the slide were twelve hours old.
First-pass yield sat at 94% and would not move. Every engineer had a theory: solder paste, feeder wear, the reflow profile on line 4. Nobody could prove one, because defects lived in the AOI machine, downtime lived in a spreadsheet, and maintenance lived in a notebook on the technician's bench.
What changed, step by step
One connected loop: audit, defect, fix, root cause, kaizen, standard, recognition. Open any step to see what it did at this plant.
Step 1 · Audit · 5SESD and line-readiness walks on a cadence
Line leaders walk their line at the start of every shift with a phone: ESD straps and mats, feeder carts, MSL bake logs, label stock. The walk takes eight minutes and replaces a paper form that was signed at the end of the shift, not the start. In week one, four of six lines failed the ESD check on at least one station.
Step 2 · DefectsAOI escapes, ESD gaps and leaks on one board
Quality findings, safety findings and machine problems now land on the same board, each with an owner and a date. The tier-1 meeting opens that board instead of a slide, so the conversation is about what is red today rather than what was red yesterday. Meeting length fell from twelve minutes to seven.
Step 3 · Fix-PlanMaintenance stopped living in a notebook
Every placement machine, reflow oven and AOI got a record, a preventive plan drafted from the manuals, and a spare-parts list with reorder points. Breakdowns are reported in the operator's own words, in Malay, Tamil or English, and arrive as a work order the technician can start from the line.
Step 4 · Root cause · A3The line 4 tombstoning got an A3
The team pulled AOI defects, reflow temperature logs and maintenance history into one A3. The fishbone pointed at the oven, and the 5-Why thread found a zone-6 heater that had been drifting for months, masked by a profile tweak each time it was noticed. The heater was replaced and the profile reset. Tombstoning on line 4 dropped 80% in a month.
Step 5 · Kaizen · savingsChangeover minutes became money
Changeover kaizens moved feeder prep offline and standardised stencil storage. Each one carries an expected saving and, after 60 days, a finance-verified actual. Nine months in, the ledger reads $410k a year, mostly from scrapped boards that are no longer scrapped and overtime that is no longer needed.
Step 6 · OPL → Skill matrixEvery new operator learns the same line
The reflow and ESD standards became one-point lessons with photos from the plant's own lines. The skill matrix shows who is certified on which machine, so the shift lead stops guessing who can run line 4 on a Sunday.
Step 7 · LeaderboardThe morning brief names tomorrow's breakdown
Factory Intelligence reads the downtime, maintenance and quality history every morning and lists what to look at first, with the evidence beside each item. Twice in the first quarter it flagged a placement head whose pick errors were climbing before the machine stopped. Unplanned SMT downtime fell 38%.
More case studies
All 9 →Illustrative deployment story: a composite of typical LeanOS rollouts; company and names are fictional.