SMT Assembly with Consigned Components
Consigned SMT assembly works only when buyer-supplied parts are treated like controlled production inventory. YourPCB maps BOM ownership, audits the kit, checks MSL risk, and defines attrition before the line is scheduled.
01005
SMT component size supported on existing assembly pages
0.3 mm
fine-pitch QFP/BGA capability reference
IPC-A-610
Class 2 standard and Class 3 available
Hybrid
turnkey plus consigned sourcing by BOM line
Where Consigned SMT Builds Usually Fail
Surface-mount assembly is well documented in public references for surface-mount technology and IPC electronics standards, but consignment adds a supply-chain layer that generic SMT pages rarely explain. The factory can place 01005 parts and inspect BGAs, yet still lose schedule if the buyer-supplied kit is short, unlabeled, moisture-exposed, or missing a no-substitution rule.
This page is intentionally different from the general SMT PCB assembly page. It targets teams that already own components and need the assembly process to protect those parts. The core decision is not whether YourPCB can place the components; it is whether the kit, traveler, attrition rule, and test plan are controlled enough to finish the build without emergency sourcing.
Consigned Assembly Controls
BOM Ownership Map
Each BOM line is marked turnkey, customer-supplied, approved alternate, no-substitution, programmed, or buyer-controlled before purchasing and setup begin.
Receiving and Kit Audit
Incoming reels, trays, tubes, and cut tape are checked against the packing list so shortages and label mismatches are found before the SMT line is scheduled.
MSL Handling Review
Moisture-sensitive packages are reviewed for sealed bags, humidity cards, floor-life status, and bake permission before reflow exposure.
Attrition Planning
The build traveler states spare-part rules for fine-pitch ICs, BGAs, LEDs, RF parts, and programmed devices where replacement is slow or expensive.
Mixed Sourcing Support
YourPCB can source commodity passives and standard connectors while the buyer consigns allocation-sensitive or customer-approved components.
Unused Parts Return Control
Remaining parts can be counted, labeled, and returned or held for repeat orders, reducing confusion when a prototype turns into a pilot build.
Technical Scope and RFQ Inputs
| Best-fit builds | Prototype, pilot, low-volume, repair, allocation-sensitive, and customer-controlled SMT assembly programs |
|---|---|
| Supported packages | 01005 passives, fine-pitch QFP/QFN, BGA, LEDs, RF modules, connectors, and mixed SMT/THT assemblies |
| Receiving inputs | BOM, packing list, part labels, quantity by line, packaging type, lot/date code needs, MSL condition |
| Assembly inputs | Gerber or ODB++, NC drill, XY placement, assembly drawing, polarity notes, stencil notes, test requirements |
| Standards cited | IPC-A-610 for workmanship, J-STD-033 for MSL handling, EIA-481 packaging expectations where tape/reel matters |
| Out of scope | We do not assume liability for counterfeit, damaged, or unlabeled customer-supplied parts without agreed incoming inspection scope |
The most useful trade-off is selective control. Consign the parts that truly need buyer ownership, then let the factory source commodity lines when availability and alternates are straightforward.
Engineer's Note
"The cleanest consigned SMT builds have a boring receiving report. Every bag, reel, tray, shortage, MSL note, and no-sub part is known before the first stencil print. Surprises at placement time are what make consignment expensive."
Hommer Zhao, Technical Director
Production Workflow
1
Quote the Supply Model
The quote starts with ownership, not only quantity. We identify which parts YourPCB buys, which parts the customer supplies, which alternates are approved, and which lines cannot be substituted without written approval.
2
Audit the Physical Kit
Receiving checks the physical kit against the BOM and packing list. A 500-board build can stop because one cut-tape bag is short, one IC label is ambiguous, or a programmed part arrives under the wrong revision.
3
Protect Sensitive Components
MSL parts, LEDs, sensors, BGAs, and fine-pitch ICs are handled according to the agreed release notes. If a bag is open or humidity status is unclear, the traveler needs a documented bake, hold, or buyer-decision path.
4
Build, Inspect, and Record Attrition
The SMT line runs with the same placement, reflow, AOI, X-ray, and test discipline as turnkey assembly. The difference is that shortages, attrition use, and rework consumption are recorded because the buyer owns part inventory.
5
Close the Loop
After inspection and test, unused components are counted and dispositioned. For repeat orders, the shortage list and overage rule become part of the next RFQ instead of a surprise during receiving.
Consigned SMT Assembly FAQ
What does consigned component SMT assembly mean?
Consigned component SMT assembly means the buyer supplies some or all parts while the assembly supplier handles PCB fabrication, stencil setup, paste printing, placement, reflow, inspection, and test. The practical risk is ownership clarity: every BOM line should state whether it is customer-supplied, factory-sourced, approved alternate, or no-substitution. For IPC-A-610 Class 2 or Class 3 work, the kit also needs labels, date codes, moisture status, and enough attrition quantity to avoid stopping the line.
I want to send 200 expensive ICs for a prototype build. How much extra should I provide?
For 200 expensive ICs, send the exact build quantity plus a written attrition rule before production starts. The right spare quantity depends on package type, placement risk, rework allowance, and whether the component can be replaced quickly. A simple 0603 resistor may need a different overage rule than a fine-pitch QFN, BGA, RF module, or programmed microcontroller. If no spare can be provided, the traveler should mark that line as critical and require buyer approval before any rework consumes additional parts.
How do you control MSL parts when customers supply components?
MSL-sensitive parts should arrive sealed, labeled, and traceable to the moisture barrier bag, humidity indicator, and floor-life condition. If the bag is open, missing, or expired, the build may need a bake decision before SMT placement. J-STD-033 is the common handling reference for moisture-sensitive surface-mount devices, and the buyer should state whether baking is allowed for each part number. This is especially important for BGAs, QFNs, sensors, LEDs, and fine-pitch ICs.
Can a build mix turnkey and customer-supplied parts?
Yes, mixed turnkey and consigned SMT assembly is often the best sourcing model when the buyer controls long-lead ICs, programmed parts, or allocation-sensitive devices while the factory buys passives, connectors, and standard semiconductors. The BOM must assign ownership by line item, not by verbal agreement. It should also define approved alternates, no-substitution parts, packaging type, reference designators, and who pays for shortages or rework consumption.
What files should I send with a consigned SMT assembly kit?
Send Gerbers or ODB++, NC drill data, BOM, XY placement file, assembly drawing, polarity notes, approved alternate list, test requirements, and a packing list that matches each physical reel, tray, tube, or cut tape bag. The kit audit is faster when labels include manufacturer part number, quantity, date code if controlled, lot code if controlled, and customer project revision. Missing placement data or mismatched BOM quantities can delay a 1-day receiving check into a multi-day clarification loop.
When is full turnkey assembly better than consignment?
Full turnkey assembly is better when the buyer wants the supplier to own shortages, distributor coordination, substitutions, and purchasing records. Consignment is better when parts are expensive, scarce, programmed, customer-approved, or already held in the buyer's inventory. Many low-volume programs use a hybrid model: the buyer consigns 5 to 20 controlled lines, while YourPCB sources commodity passives and common connectors through the normal assembly workflow.
Related Services
SMT PCB Assembly
Use this page for the broader surface-mount process, fine-pitch placement, reflow, AOI, and BGA assembly scope.
Custom PCB Assembly
Useful when consigned parts are one part of a larger product-specific assembly workflow.
PCB Assembly Prototype
Relevant when the consigned kit supports engineering samples, bring-up boards, or early validation lots.
Turnkey Electronics Manufacturing
Compare this when the buyer wants YourPCB to own sourcing, purchasing risk, and supplier coordination.
Send a Consigned Kit for Review
Share the BOM, XY file, Gerbers, packing list, MSL status, overage rules, and test requirements. We will identify shortages and responsibility gaps before the assembly slot is committed.
Request Kit Audit and Quote