This article is part of the How to Buy CNC Machining: Quotes, Costs, MOQ & Supplier Selection on CNX Precision.
A complete CNC RFQ checklist saves days of back-and-forth. You send one clear request. The shop quotes it quickly and accurately. Everyone wins. Missing details cause questions, delays, and guesswork. Worse, guesswork leads to parts that do not match your expectations. This article gives you a proven list. Use it for every request, from prototypes to production. The CNC RFQ checklist below covers every essential detail.
Why a Complete RFQ Matters
Machine shops price parts from the information you provide. Every missing detail becomes a question. Every question adds time to the quote. In a busy week, incomplete RFQs may wait behind complete ones. Therefore, completeness is a competitive advantage. It moves your project to the front of the queue.
Complete information also protects quality. The shop knows the material, tolerance, and finish. The programmer sets up the job correctly from the start. The inspector measures the right features. As a result, parts match the drawing the first time. Rework drops, and trust grows. Complete files arrive faster when you follow a CNC RFQ checklist. This is the real value of a good request.
Incomplete requests create familiar problems. The shop guesses a material, and the buyer corrects it. The quote changes, and the clock restarts. Sometimes a part arrives with the wrong finish because no one specified it. These mistakes cost time and money on both sides. Therefore, think of the RFQ as a contract. If a detail matters to you, put it in writing.
Good RFQ habits compound over time. First, you keep a master folder for every project. Then you reuse the same checklist for each revision. Consequently, quotes arrive faster with each order. Also, your shop learns your preferences. For example, they know you prefer anodized 6061 or bead-blasted stainless. As a result, follow-up questions drop. In short, the checklist becomes a shared language between you and your supplier.
The Core CNC RFQ Checklist
Start with the core CNC RFQ checklist, then add industry extras. Copy this list into your next request. Then confirm every box is ticked before you press send.
- Part name and revision. Name the part and note the drawing revision. This prevents version confusion.
- 3D model file. Send STEP or IGES as the master format. Add native CAD files when possible.
- 2D drawing PDF. Include dimensions, tolerances, and notes. The drawing is the contract for quality.
- Material grade. State the exact alloy, such as 6061-T6 aluminum or 304 stainless steel.
- Quantity. State the number of parts. Add future quantity plans if you know them.
- Surface finish. Choose raw, bead blast, anodized, or powder coated. Define the color if needed.
- Tolerances. Mark standard and critical dimensions. Use the drawing for anything special.
- Threads and inserts. List thread sizes, classes, and any pressed-in inserts.
- Edge breaks and deburring. State sharp or broken edges. Deburring is standard, but confirm it.
- Packaging and labeling. Add special packaging needs for export, ESD, or clean rooms.
This CNC RFQ checklist works for any shop. It also works for any material or process. Add your own items as projects grow. For example, medical parts may need cleanliness certificates. Aerospace parts may need material traceability. Automotive parts may need PPAP documents. Your checklist should grow with your industry.
File Formats and Drawing Details
File format matters more than people think. STEP files are the universal standard for 3D models. IGES is older but still common. Both carry geometry without losing shape data. Native files, like SolidWorks or Fusion 360, preserve features and history. Sending both formats gives the shop maximum flexibility.
Your 2D drawing should be clean and complete. Include a title block with part name, revision, and material. Mark critical tolerances explicitly. Specify thread callouts, surface finish symbols, and edge notes. If a dimension is missing, the shop should ask instead of guessing. A drawing review service can catch these gaps before quoting.
Before you export, check the units in your CAD software. A millimeter part exported as inches becomes ten times too large. Therefore, set units first, then export. Also verify that the export includes the latest revision. Finally, run a quick geometry check to catch open surfaces. These three steps take minutes and prevent serious errors.
Use the table below to match files to their purpose.
| File Type | Best For | Notes |
|---|---|---|
| STEP (.stp) | Master 3D geometry | Universal, precise, preferred |
| IGES (.igs) | Legacy CAD exchange | Works with older systems |
| Native CAD | Feature history | Useful for quick edits |
| PDF drawing | Dimensions and notes | The quality contract |
After You Send the RFQ
Once the RFQ is sent, the shop starts a DFM review. An engineer checks the design for manufacturability. You may receive questions or suggestions. Reply quickly and clearly. Then the shop prepares a formal quotation. It lists unit price, tooling, lead time, and payment terms. Review everything and ask questions before approval.
Good communication keeps the project on schedule. Therefore, reply to questions the same day. Also, send any design updates in writing. Finally, nominate one contact person for the project. These simple rules prevent confusion. Many delays start with a missed email, not a slow machine.
A good quote includes assumptions. For example, it may state that tolerances apply to machined surfaces only. It may list finish as cosmetic or functional. Read these notes carefully. They define the agreement. If anything conflicts with your expectations, say so before production starts.
Finally, confirm the project timeline. Ask when sampling happens and when production finishes. Ask how shipping is handled and who covers customs for export orders. Clear answers now prevent surprises later. The CNC RFQ checklist ends where the project plan begins. For a smooth process, choose a partner like CNX Precision that reviews every file before quoting.
FAQ About CNC RFQ Checklists
Can I send only a 3D model without a drawing?
Yes, for simple parts. However, a drawing is safer for tight tolerances and threads. Many shops quote from models alone. Then they confirm critical details in the DFM review. When in doubt, include a simple PDF drawing.
How many RFQs should I send before choosing a shop?
Send the same complete package to two or three shops. Compare price, lead time, and communication. Also, ask about their DFM review process. The lowest price is not always the best value. Pick the shop that answers clearly and checks your design.
What if I do not know the material or finish?
Tell the shop your application and environment. The engineer will recommend options. For example, outdoor parts may need anodized aluminum or stainless steel. You decide after seeing the recommendation and price.
A complete request is a professional request. The CNC RFQ checklist above covers every essential detail. Files, material, quantity, finish, and tolerances. Send them all at once, and your quote arrives fast. Missing details, and your project slows down.
Ready to send your next RFQ the right way? Prepare your files with this checklist, then contact CNX Precision. Our engineers review drawings and models as part of every quotation. You will get a clear, complete answer the first time. Use the checklist today and see the difference.
For related information, see our guide to cnc machining service and 5-axis cnc machining and cnc milling vs turning and cnc machining tolerances.