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Capability 04 — Manufacturing

The last ten percent of quality is decided on the line.

A good prototype does not prove a production process. What proves it is a defined test at every gate, a fixture that measures the same thing every time and a record that ties a shipped unit back to its lot.

Production floor

The line you audit is ours.

Serow runs its own manufacturing center: a tool room, injection molding, SMT, silk-print and twelve remote-control assembly lines. A tooling change does not wait in an outside factory’s queue.

12
Remote-control lines

The largest line group on site.

100
Tool sets / year

In-house tool room capacity.

3
SMT lines

YAMAHA YV100II, supporting our own boards.

6
Assembly lines

Sub-assembly and final build.

ProcessLinesNote
Remote-control assembly 12 Final build, test and pack
General assembly 6 Sub-assembly and accessories
Ultrasonic welding 5 Housing sealing
Laser 4 Laser machines
Silk printing 2 Legends and decoration
SMT 3 YAMAHA YV100II
Tooling 100 / year In-house tool room

SMT is a supporting process for our own boards; the volume business is assembly, tooling and test.:

Production flow

Five gates between components and a sealed carton.

Each gate has an accept criterion and a record. A unit that fails a gate is quarantined, not reworked quietly and returned to the same lot.

Gate 01

Incoming inspection

Components, PCBs, keypads and housings are checked against the approved sample and drawing. Critical items — radio module, crystal, battery contacts, keypad material — are checked per lot.

Record: incoming inspection sheet
Gate 02

SMT and board test

Boards are assembled, reflowed and inspected. A board-level test checks power, key scan, IR output and radio transmission before assembly into the housing.

Record: board test log with fixture ID
Gate 03

Final assembly

Keypad, board, battery contacts and housing are assembled on a defined fixture. Sealing, screw torque and battery-door fit are checked against the work instruction.

Record: assembly line check
Gate 04

Functional test

Every unit is tested for key function, IR output, radio range and current draw. Units are tested with the firmware version released for that order, not a generic build.

Record: per-unit test result
Gate 05

Packaging and traceability

Accessories, labels and language variants are checked against the order. The carton label carries the lot, quantity and firmware version so a field issue can be traced back.

Record: packing list and lot record

Inside the line

Injection moulding — housing tools run on this floor.
01Injection moulding — housing tools run on this floor.
EDM and machining — inserts cut and repaired in the toolroom.
02EDM and machining — inserts cut and repaired in the toolroom.
SMT — placement, reflow and board test before assembly.
03SMT — placement, reflow and board test before assembly.

Quality gates

What is measured, and with what.

CheckMethodFrequencyRecord
Key function Fixture presses every key; receiver confirms code Every unit Per-unit pass/fail
IR output Receiver or optical sensor confirms carrier and frame Every unit Per-unit result
Radio range Fixed-distance test through the final housing Every unit or sampled per lot Test log
Current draw Sleep and active current against the approved limit Sampled per lot Measurement record
Housing fit Gap, flush and battery-door check against the limit sample Sampled per lot Visual inspection sheet
Sealing Program-specific test when an IP target applies Per validation and sampled in production Test report

Sampling levels and accept criteria are agreed in the production test specification. They are not left to the operator’s judgement on the day.:

Traceability

When a fault occurs at the customer site, we trace it to the batch rather than to guesswork.

Every order carries a lot record: component lots, firmware version, test fixture, test results and packing list. When a unit fails at the customer site, the record narrows the question to a specific batch instead of the whole product history.

For configured products, the record also includes the configuration file — key map, language set and property code — so a replacement can be matched to the original.

What ships with the order
  • Packing list with lot and quantity
  • Firmware version and configuration reference
  • Functional test summary
  • Approved sample retained for reference
  • Certification copies for the shipped model and market

Capacity

We schedule line time per program — it is not a price-list slot.

A headline monthly capacity is meaningless if your program shares a line with three others during peak season. We confirm the allocation for your order window before you commit to a launch date.

Pilot builds are scheduled with the same fixtures that will run mass production, so the process is proven before volume. If a fixture cannot keep up, we find that out on the pilot, not in the first shipment.

We schedule line time per program — it is not a price-list slot.

Questions

Manufacturing FAQ

Can we audit the line or the test records?
Yes, within the terms of the supply agreement and with reasonable notice. We can walk through the production flow, the test fixtures and the lot records for your order. Customer-specific audits are scheduled rather than open-ended.
What happens when a unit fails functional test?
It is quarantined with a failure code. Rework is allowed only for defined defect classes with an approved procedure, and reworked units are re-tested. Units that cannot be brought back to specification are scrapped, not mixed into the lot.
Do you test every unit’s radio range?
Every unit goes through a radio transmission check. Full range testing is usually sampled per lot because a range chamber is a slower test. The exact split is written into the production test specification for your program.
Can production move to another site later?
The design package, fixtures and test specification are written so a competent site can take over. In practice, the test fixtures and the approved sample are the hard parts to transfer, so a planned transfer should include building them at the new site.

Related: Prototype to Production Quality & Certifications

Start a project

Ask for the test specification before the price.

The test specification tells you what the unit price actually buys. We would rather discuss that first.

Typical reply within one business day