A useful casting RFQ is not only a part name and a target price. The drawing, material, quantity, machining areas, inspection requirements, and final use decide whether the quote is practical.
Short answer: send the 2D drawing, 3D model if available, material grade, quantity, application, machined surfaces, tolerance notes, surface finish, inspection requirements, and delivery expectations. If something is not final, mark it as open for review.
Many buyers contact a supplier with a part name such as pump body, gearbox housing, bracket, or aluminum cover. That is a starting point, but it is not enough for a serious casting quotation. The supplier needs to know which surfaces must seal, which holes will be machined, where the part fits in an assembly, and what inspection documents are required.
1. RFQ Information Checklist
| Information | Why it matters | Buyer note |
|---|---|---|
| 2D drawing | Shows dimensions, tolerances, material notes, threads, surface finish, and inspection requirements. | Send the latest revision and mark uncertain areas. |
| 3D model | Helps review part shape, wall thickness, ribs, bosses, draft, machining allowance, and tooling risk. | Useful for housings, covers, pump bodies, and complex brackets. |
| Material grade | Affects casting route, strength, corrosion resistance, machining, surface treatment, and cost. | If unknown, describe the application and working condition. |
| Quantity | Changes tooling choice and process selection. | Separate sample quantity from annual or batch quantity. |
| Machined areas | Controls allowance, datum selection, fixture planning, and final inspection. | Mark bearing seats, sealing faces, holes, threads, and mounting faces. |
| Inspection needs | May affect process, cost, lead time, and documentation. | Confirm CMM, material report, X-ray, leakage, or pressure test early. |
2. What We Review Before Quotation
- Whether the drawing can be cast with the requested material and wall thickness.
- Whether sand casting, die casting, gravity casting, or another route is more practical for the quantity and geometry.
- Whether ribs, bosses, hot spots, or thin sections may create shrinkage, porosity, or deformation risk.
- Whether machining allowance is enough for sealing faces, bearing seats, holes, threads, datums, and flat mounting surfaces.
- Whether the requested inspection method matches the functional risk of the part.
- Whether packing must protect machined surfaces, coating, threads, or visible surfaces during shipment.
3. Process Selection Questions
The casting process should not be chosen only by part name. A housing may be sand cast, die cast, or gravity cast depending on size, material, wall thickness, quantity, and final machining. A pump body may need a different route if pressure, leakage, or corrosion risk is involved.
- Is the part large, heavy, or lower volume? Sand casting may be practical.
- Is it an aluminum or zinc part with repeat production and thin walls? Die casting may be practical.
- Is it an aluminum part where better density or lower tooling pressure matters? Gravity casting may be reviewed.
- Does the final part need tight holes, threads, bearing seats, or sealing faces? Plan CNC machining from the start.
4. Common RFQ Mistakes
- Sending only a photo and asking for a firm production price without dimensions or material.
- Not marking machined surfaces, then discovering after casting that the allowance is not enough.
- Choosing die casting only because the surface looks better, while the quantity does not justify tooling cost.
- Ignoring porosity risk near sealing faces, pressure areas, or machined bores.
- Asking for inspection reports after production instead of confirming them before quotation.
- Comparing quotes without checking whether they include tooling, machining, finishing, inspection, packing, and export details.
5. Example RFQ Notes by Part Type
| Part type | Details to mark | Often linked page |
|---|---|---|
| Gearbox housing | Bearing seats, mounting faces, datum surfaces, hole positions, flatness, inspection points. | Cast Housings |
| Pump body / valve body | Sealing faces, ports, flanges, threads, pressure or leakage requirement, material documents. | Pump & Valve Castings |
| Aluminum cover or enclosure | Visible surfaces, ribs, cover fit, coating, machined holes, burr control. | Aluminum Die Casting |
| Bracket or base | Load areas, mounting holes, flat faces, ribs, surface treatment, packing protection. | Cast Brackets & Structural Parts |
FAQ
Can you review a project without a final drawing?
Yes, but the answer will be preliminary. Send the current drawing, sample photos, or existing part details first. A final quote usually needs confirmed dimensions, material, quantity, and machining requirements.
Should machining be discussed before or after casting?
Before casting. Machining allowance, datum selection, clamping, hole position, sealing faces, and inspection access can all affect tooling and process decisions.
What if I do not know the material?
Describe the application, load, corrosion condition, temperature, contact medium, and target cost. Material options can then be reviewed against the part function and casting process.
Related Buyer Guides
Send the drawing, material, quantity, machined areas, tolerance notes, inspection requirements, and delivery expectations. We will review the practical casting and machining route before quotation.