A useful custom-cable RFQ lets engineering understand the assembly without a chain of clarification emails. You do not need a perfect CAD drawing, but you should define both ends, wiring, cable construction, mechanical details, quantity, and how the sample will be approved.
1. Define End A and End B
For each end, list connector family, contact count, row layout, male/female contact gender, mounting or screw-lock hardware, and backshell or overmold preference. Add manufacturer part numbers when they are mandatory.
If one end is bare wire, terminal, RJ-style plug, or another connector family, define it with the same level of detail.
2. Attach the wiring definition
Provide a pin-to-pin table, equipment pinout, or approved sample. Mark NC positions, jumpers, and shield/chassis connections explicitly.
For DB9-to-DB25 or other transition cables, include signal names when available so engineering can review function as well as physical contact numbers.
3. Specify cable construction
State finished length, conductor or cable requirements, shielding, jacket/environment needs, flexibility, and any branch lengths. If you only know the application, describe the environment so the manufacturer can propose a construction for review.
Avoid specifying materials by habit when the real requirement is mechanical or electrical performance.
4. Add mechanical requirements
Define cable exit direction, panel mounting, backshell size constraints, strain relief, labels, split points, and any dimensional limits. Installation photos can be valuable when clearance is tight.
For panel assemblies, include the cutout or mating hardware information.
5. State quantity and project stage
Tell the supplier whether you need one engineering sample, a pilot batch, or a repeat production quantity. Include estimated annual volume when it affects tooling, process, or packaging decisions.
Separate sample quantity from production quantity so the quotation can reflect the actual project path.
6. Define approval and testing
State how the sample will be approved and what inspection evidence is required. At minimum, the factory should build and test against the approved wiring definition.
For OEM programs, freeze the approved drawing revision before volume production.
A compact RFQ template
Project/application; End A; End B; pinout/drawing; finished length; cable construction; shielding; mounting/backshell; labels; quantity; sample requirement; test/inspection requirement; packaging; target delivery.
Filling these fields usually produces a faster and more comparable quotation than sending only a product photo and asking for a unit price.
Information package to attach
- End A/End B
- Pinout/drawing
- Length/construction
- Shielding
- Mechanical details
- Quantity
- Testing/approval
What slows approval
Sending only photos and quantity; omitting the wiring definition; mixing sample and production quantities; and leaving acceptance criteria until after the quote.
Continue the specification
Use the industrial D-Sub cable selection to confirm the first related decision, then review the OEM D-Sub cable checklist before you freeze the order.
What to send BespokeCable
BespokeCable’s published customization workflow covers inquiry and specification discussion, quotation, sample making, and mass production after sample approval. Your RFQ should therefore separate the technical definition, sample quantity, production quantity, approval method, and packaging or labeling requirements.
Start the BespokeCable review
Send BespokeCable your equipment models, connector details for both ends, approved pinout or verified sample, finished dimensions, shielding and mechanical requirements, quantity, and sample-approval criteria. You can then review a defined assembly instead of relying on a generic D-Sub description.
