Guides · 24 October 2026
How to price inspection on a CNC quote: first article, in-process and final checks
Every part you ship has been measured by someone, and that someone is paid. On simple work the checks are a few minutes the operator does at the machine. Once a buyer asks for a first article report, a sampling plan or certificates, inspection becomes hours per batch, and it belongs on the quote like any other operation.
The four kinds of inspection time
- First article inspection. Every dimension and note on the drawing measured on the first part and written up. Aerospace work often asks for it in the AS9102 format. It is paid once per batch, or once per new revision, and it grows with the number of characteristics on the drawing, not with the size of the part.
- In-process checks. Critical features measured every so many parts while the batch runs, so a worn tool is caught before it makes scrap.
- Final inspection. A sample, or every part, checked before packing, against the plan the buyer specified or your own.
- Paperwork. Certificate of conformance, material certificates, the inspection report itself. Small each time, but it is someone's time.
Count characteristics, not features
For a first article, number the drawing: every dimension, tolerance, thread, surface finish and note that can be checked is one characteristic. Then allow a time per characteristic for measuring and recording it. Two to four minutes is common for hand instruments on a prismatic part; a characteristic that needs a special gauge, a surface finish tester or a setup on a CMM takes longer. Add time for the report itself.
If the part goes on a CMM, the program is written once. Price it like CAM programming: once per order, and not again on a repeat.
A worked example
An aluminium bracket, 50 off. The drawing has 40 characteristics. The buyer wants a first article report, a check of the bore and the thread every 10 parts, 8 parts checked at final inspection, and a certificate of conformance with the material certificate. Inspection time costs US$75 an hour.
| Inspection | How it is worked out | Minutes | Cost |
|---|---|---|---|
| First article | 40 characteristics × 3 min, + 30 min report | 150 | US$187.50 |
| In-process | 5 checks × 4 min | 20 | US$25.00 |
| Final | 8 parts × 6 min | 48 | US$60.00 |
| Certificates | CoC and material certificate | 15 | US$18.75 |
| Inspection | 233 | US$291.25 |
That is US$5.83 a part over 50 parts, before overhead and margin. The first article alone is almost two thirds of it, and it does not get smaller with a smaller batch: on 10 parts it is US$18.75 a part on its own.
What to look for on the request
- “FAI required”, “AS9102”, “PPAP”. A formal first article, with a report in the buyer's format.
- A sampling plan or AQL. It sets how many parts you check at final inspection. Ask for it if it is not stated.
- Critical or key characteristics. Often 100% inspection of those features, which is a time per part, not per batch.
- Certificates. Conformance, material, and anything from outside processing, such as the anodiser's or heat treater's certificate.
- Tight tolerances. They need slower measurement and better instruments; the guide on pricing tight tolerances goes through the rest of their cost.
Common mistakes
- Folding inspection into the cycle time. It hides a cost per batch inside a cost per part, so small batches come out too cheap.
- Pricing the first article once per customer. A new revision of the drawing usually means a new first article.
- Forgetting the report. Measuring is half of it; typing up 40 results in the buyer's format is the other half.
- Giving away paperwork. If certificates are asked for on every order, they are a cost on every order.
In Spindlewise, inspection can be its own operation on the line, with a time per batch for the first article and a time per part for checks, or a cost per order such as a report fee. Each quantity on the quote then carries its share, and the costing shows how much of the price is inspection.