OEM buyer guide · drawing-led quotation

What to send for an accurate CNC machining or mold plate quote.

A drawing alone may not tell a supplier which features control function, what must be measured, or what belongs in the delivery package. This checklist helps buyers define those points before a price and lead time are agreed.

Send a confidential RFQ →See drawing-review examples

The minimum RFQ package

Send a revision-controlled 2D drawing and a matching 3D CAD model, preferably STEP. Identify the part name or internal reference, requested quantity, material grade, finish, intended use, shipping destination and target date. If a drawing revision is pending, say so before tooling or programming starts.

Mark functional dimensions, fit surfaces, threads, datum references and geometric tolerances. A tolerance capability shown on a supplier website is not a promise that every feature on your part can meet that number; feasibility depends on geometry, material, setup and measurement method.

Define the evidence you need

Specify whether you require a material testing report, a first-article report, sampled final inspection, a CMM report, surface-finish readings or a particular inspection template. Identify the dimensions to report and the sample quantity. Agree these deliverables at quotation rather than assuming they accompany every shipment.

From two real customer drawings

Why a short drawing review can change the quotation.

We reviewed two customer-supplied tooling drawings for this guide. Their images, part numbers, exact dimensions and customer identities are withheld; the observations below describe review questions, not completed production results.

Engineer reviewing a CAD model at the Hongye manufacturing site — Engineering CAD review at the factory; this is not an image of either confidential customer drawing.

Plate with side-access features

One drawing combines opposed reliefs, a central bore, threaded side features and several locating positions. Before selecting a milling route, the buyer and manufacturer should agree which face is the primary datum, which features must align across setups, and whether tool access calls for a secondary process.

Ask for: a datum and setup proposal, clarification of critical bore and thread relationships, and an inspection method for the specified features.

Repeated-cavity mold plate

The other drawing combines repeated cavity groups with a dense hole pattern and material and heat-treatment requirements. Repetition creates a different risk: cavity-to-cavity consistency and position relative to the drawing datums matter more than one isolated feature.

Ask for: a machining and heat-treatment sequence, clarity on which features are finished after treatment, and an agreed measurement plan for critical positions.

These are anonymized drawing-review examples only. We do not publish customer drawings or claim a production quantity, inspection result or acceptance outcome for either project. See the separate photo-documented work →

Questions to settle before a purchase order

Question	Why it affects the quote	Buyer input
Which features are critical?	Controls setup, process choice and inspection time.	Mark functional datums, fits and GD&T on the controlled drawing.
What material evidence is required?	Report type and traceability affect sourcing and documentation.	Specify grade, standard and certificate or testing report scope.
What inspection is acceptable?	CMM is useful for suitable geometry, but not every feature or part needs the same method.	List measured features, sample size, method and acceptance criteria.
What is included in delivery?	Finishing, assembly, export packing and reports affect price and time.	State finishing, packaging, destination and document requirements.

Typical production lead time is 7–25 days after project review; the committed date depends on material availability, complexity, quantity, finishing and inspection. Read the inspection guide →

For process selection, compare CNC milling, CNC turning and mold manufacturing. If you are unsure which applies, send the complete drawing for review.