RFQ Preparation
What Information Is Needed for a Custom Gear RFQ?
A complete RFQ helps engineering teams review feasibility, choose a manufacturing route, and quote the same technical scope that the buyer expects to receive.
SINOF Engineering Team · · 7 min read
Why a complete RFQ matters
A gear quotation is a technical agreement in progress. Tooth geometry alone is not enough to select material, heat treatment, tooling, finishing, inspection, packaging, or a realistic production route. Missing information creates assumptions, and different assumptions make supplier quotations difficult to compare.
Technical data checklist
| Information | What to provide | Why it affects the quotation |
|---|---|---|
| Gear geometry | Gear type, module or DP, tooth count, pressure angle, helix data, profile shift | Defines the tooth system, tooling, mating conditions, and measurement method |
| Blank and interfaces | Outside dimensions, bore, hub, keyway, spline, thread, datum features | Defines turning, milling, broaching, grinding, and setup requirements |
| Material | Exact grade and permitted equivalents | Affects availability, machining, heat treatment, distortion, and certification |
| Heat treatment | Process, case depth, core hardness, final hardness, areas to mask | Affects process sequence, stock allowance, distortion control, and testing |
| Accuracy | Applicable standard, grade, backlash, runout, profile and lead requirements | Defines finishing and gear-inspection scope |
| Quantity | Prototype quantity, annual demand, batch size, and schedule | Changes tooling, process planning, and unit economics |
| Documentation | Material certificate, hardness report, dimensional report, gear chart, traceability | Defines inspection time and record-retention requirements |
Application and commercial context
Application data helps the supplier identify conflicts that a drawing may not reveal. Share speed, torque, duty cycle, lubrication, temperature, shock load, noise expectations, mating components, installation constraints, and whether the gear is safety-critical. The buyer retains design authority, while the manufacturer can provide manufacturability observations.
- Separate prototype, first-article, and production quantities.
- State the delivery location and Incoterm requested for commercial comparison.
- Identify controlled or customer-supplied material requirements.
- List inspection characteristics that require measured values rather than pass/fail confirmation.
- Attach the latest drawing revision and explain any open technical questions.
Before you send the RFQ
- Check that the 2D drawing and 3D model show the same revision.
- Mark critical characteristics and define their datums.
- Remove conflicting general and feature-specific tolerances.
- Confirm units, quantity, material, heat treatment, and reporting needs.
- Ask the supplier to identify assumptions and exceptions in the quotation.
If some values are unknown, say so explicitly. An engineering review can then focus on the missing decisions instead of treating silence as approval for a supplier assumption.
Frequently asked questions
Is a 3D model enough for a custom gear quotation?
A 3D model helps with geometry, but a controlled 2D drawing is still recommended for tolerances, material, heat treatment, surface finish, inspection, and revision requirements.
Can a physical sample be used when no drawing exists?
A sample can support an initial review, but wear and damage may hide the original geometry. Production should follow mutually agreed drawings and acceptance criteria.
Should prototype and production quantities be quoted together?
Yes. Separate quantities let the supplier explain prototype setup costs and propose a different production process or tooling strategy for repeat demand.
Discuss your gear drawing with our team
Share the drawing, quantity, material, accuracy target, heat treatment, and application context for engineering review.
Request drawing review