What to put in the RFQ, in full
A good RFQ is a small document, not a price enquiry. The difference in return quality is immediate, because a factory cannot quote what it cannot see, and it will fill gaps with assumptions that favour its own process rather than yours.
- The 3D model in STEP and a dimensioned 2D drawing; both, not one.
- Material grade and thickness — in millimetres, with gauge only as a cross-reference.
- Quantity, plus the expected repeat rate or annual volume.
- General tolerance standard and any feature-specific callouts.
- Surface finish with a colour reference (RAL or Pantone) or a written specification.
- Inspection and documentation requirements: FAI, material certificate, dimension report.
- Packaging expectations, destination and Incoterm.
- Any standard the part must meet, and who needs to see evidence.
Telling a factory from a broker
The most useful question is not "what do you make?" but "which operations do you run in-house, and on which machines?". A source factory can answer with specific equipment and capacity and will normally volunteer what it does not do. A broker redirects the question.
Practical checks that cost almost nothing: ask for the equipment list, ask for a video walk-through of the specific production area the part would run on, ask which operation is subcontracted, and ask what happens when a part fails inspection. The answers tell you more than a brochure.
Price, and why the cheapest quote is often the most expensive
Chinese pricing varies for legitimate reasons — equipment age and utilisation, material buying power, wage bands, location, and whether the shop is busy or hungry. It also varies for illegitimate ones: an under-specified process, an assumed tolerance, a substituted material or a missing finishing step.
The way to compare quotes is on scope, not on the number. Ask each supplier to state the material, the process route, the finishing specification, the inspection performed and what is excluded. Then the prices are comparable, and the surprising gaps usually explain themselves.
Quality, before and after the first shipment
Quality has to be agreed, not hoped for. On a new part we run a first article inspection against the drawing and issue the dimensional report along with the material certificate; for a stamped part the FAI is run on the die, before volume. Once the process is proven, routine production is controlled by sampling and gauges, with CMM reporting where a specification calls for it.
If your project has an acceptance plan — incoming inspection, a golden sample, a pre-shipment inspection — say so at quotation stage. Building a sampling plan around your incoming checks is straightforward when it is known in advance and painful when it is raised after the containers are packed.
IP, tooling ownership and the awkward questions
Ask them early. Who owns the die the customer paid for? Where is it stored, and what are the terms if the relationship ends? Are drawings held under NDA, and are they shared with subcontractors? How is your design protected from being sold to another buyer?
A serious factory answers these without discomfort and is willing to put the answers in a contract. Reluctance here is informative.
Logistics belongs in the design, not after it
Shipping mode, volumetric weight and packaging all feed back into design. A part designed five millimetres too large can change a carton layout and move a shipment from an efficient pallet configuration to a wasteful one. Sea freight is economical and slow; air freight is fast and priced by volumetric weight, which punishes bulky parts. Decide which one your programme can live with before the packaging is drawn.