Turnkey PCBA

Not every project should be turnkey. Some customers already buy their main devices better than we can. Some work to an approved vendor list with batch requirements that have to be respected. Partial turnkey and consigned assembly are therefore just as normal here. Process, inspection standard and records are identical across all three; the only difference is who carries the material and the lead-time risk.

The three models

Turnkey

You supply Gerber files, a BOM with manufacturer part numbers, the pick-and-place file and your test and acceptance requirements. We buy the bare boards from local fabricators and every component, then place, solder, inspect and test. The priced BOM goes back to you line by line before the order is placed, and long-lead items are named at that point rather than discovered halfway through the build.

Partial turnkey

You supply the parts you already buy well or must specify: MCU, RF modules, crystals, anything on a long lead or tied to an approved source. We buy the rest, meaning passives, discretes and connectors, and the bare board if you want us to. Assembly and test are the same as turnkey. This is the usual choice when your pricing on the main devices beats ours but you do not want to chase two hundred lines of passives.

Consigned (customer-supplied material)

You ship a full kit against our kitting list, bare boards included. We count and inspect it in, load the lines, place, solder, inspect and test. Attrition, reels and leftover material are reconciled against the work order and returned with the shipment. This suits kits already in stock and programmes where the vendor, batch or date code is fixed.

BOM review and component sourcing

The BOM is reviewed before it is quoted. We check reference designators against the layout, confirm that footprint matches value and package, look for duplicate and missing lines, and mark parts that are obsolete, end-of-life, single-sourced or written ambiguously. Where you have named a manufacturer part number we buy exactly that. Where a line is generic we select on function and operating conditions, and the quotation lists manufacturer, package and minimum packaging quantity per line so you can see what you are being offered. If a part must come from a particular source, say so on the BOM and it will be bought there or referred back to you.

Alternate parts

Nothing is substituted without written approval. When a part is out of stock, or its lead time will not meet your date, we assemble the alternates and set out the differences line by line: package, electrical parameters, voltage rating, tolerance, temperature range, and anything that touches footprint or firmware. You approve in writing or you do not. If you do not, the build waits and we keep looking.

Kitting and shortages

Kitting is verified before the job is scheduled. If one line item is short the board does not start, because half-built assemblies waiting on a rack cost more than a late start. Shortages are reported with the current lead time and the options: wait, approve an alternate, or build with the position left open for later fitting. Where a part is fitted later, the open position is recorded on the route card so the board cannot be shipped as complete.

Incoming inspection

Purchased and consigned material is checked the same way: part number, quantity, packaging labels, date code and batch against the packing list, plus a sample visual check of lead condition and pad oxidation. Moisture-sensitive devices are stored to their MSL level with time out of the dry pack recorded, and baked before use if floor life has been exceeded. Discrepancies in a consigned kit are reported before the line is loaded, not after.

Programming and serialisation

In-circuit or production programming, serial numbering and label printing are quoted job by job rather than carried at a standard rate, so name the device and firmware image, the numbering scheme and the label artwork in the RFQ and they are priced with the board.

Traceability

Material reaches the line by batch. The route card records operator, equipment and time at each step and stays with the work order. After shipment, a board number can be traced back to its material batches, its process parameters and its inspection results. Records stay on file, so a field question about a board built months ago has an answer rather than a theory.

Comparing the three models

Model	You supply	We supply	Best for
Turnkey	BOM with manufacturer part numbers, Gerber files, pick-and-place file, test and acceptance requirements
Partial turnkey	Long-lead or source-specified devices: MCU, modules, crystals, memory
Consigned (customer-supplied)	Complete kit including bare boards, shipped against our kitting list