Custom Polyurethane Casting: What to Include in an RFQ

A practical RFQ checklist for custom polyurethane casting projects, covering files, quantity, resin behavior, cosmetics, tolerances, inserts, and approval evidence.

A useful custom polyurethane casting quotation needs more than a STEP file and a quantity. The supplier must understand what the parts are for, which surfaces matter, how closely the resin should represent the end-use material, and what evidence will release the batch.

A complete RFQ reduces hidden assumptions. It also makes competing quotations easier to compare because the tooling, finishing, inspection, and approval scope are visible.

1. Send a controlled 3D model and marked drawing

Provide a neutral 3D file such as STEP together with the native CAD file when appropriate. Add a 2D drawing or marked PDF for critical dimensions, datums, inserts, threads, cosmetic surfaces, and permitted gate or parting-line areas.

State the revision and units. If several files exist, identify which one controls. Do not leave the supplier to infer whether the model or drawing is newer.

2. Separate current quantity from future demand

List the immediate batch, any first-article quantity, and the credible repeat forecast. These numbers help the supplier decide how many silicone tools, casting cycles, and finishing operations to plan. They also reveal whether another process should be compared.

If the design may change after testing, say so. A validation batch and a repeat production batch should not be quoted as though they carry the same revision risk.

3. Describe material behavior, not only a trade name

State whether the part must be rigid, impact resistant, flexible, transparent, temperature resistant, or suitable for a specific exposure. If a named resin is mandatory, provide the exact grade and required evidence. If an “ABS-like” or “rubber-like” prototype is acceptable, define what behavior must be represented.

The polyurethane casting service route should be reviewed with current technical data rather than assuming one cast resin equals an injection-molding grade.

4. Define appearance and finishing acceptance

Mark Class-A surfaces and state the color, gloss, texture, transparency, paint, coating, printing, or assembly requirements. Provide a physical sample or controlled color reference when appearance is important.

Also identify areas where trimming, a gate witness, or a parting line may be acceptable. “Good cosmetic finish” is not an inspection criterion.

5. Identify inserts, threads, and secondary work

Call out molded-in inserts, bonded hardware, threaded components, machining after casting, labels, painting, and assembly. Supply the hardware specification and clarify who provides it. Insert position and pull-out expectations may affect both mold planning and inspection.

6. Define the approval and inspection route

State whether the master pattern requires approval, whether a first casting must be signed off, and which dimensions or cosmetic zones will be inspected. Specify the expected report, sample count, mating parts, gauges, or functional test.

Use tolerances only where function requires them. Silicone tooling, cast resin, geometry, and finishing create a different capability envelope from CNC machining or injection molding, so critical features should be reviewed individually.

RFQ checklist

Controlled CAD, drawing, revision, units, and application
First batch, repeat forecast, and change likelihood
Required resin behavior and evidence
Color, texture, clarity, paint, and cosmetic zones
Critical dimensions, mating parts, inserts, and secondary work
Master and first-article approval route
Packaging, destination, requested date, and quotation breakdown

Send one controlled RFQ package

Fengnuo can review the CAD, master status, resin behavior, finish, quantity, and approval plan together, then flag missing decisions before quotation.

Submit an RFQ Package

Bottom line

The best RFQ is not the longest. It is the one that makes the part’s function, current revision, quantity, material behavior, appearance, inspection, and approval boundaries explicit. That lets the supplier quote the actual manufacturing route instead of filling gaps with assumptions.

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