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Twenty Questions to Ask a Machine Shop Before the First Order

September 21, 2026

An audit is not an interrogation. It is a way of finding out which parts of your job the shop controls and which parts it subcontracts, before that information arrives as a delay.

Capacity and capability

What did you run last month in my material, at my tolerance? Show me the drawing and the report.
How many machines can hold this part size, and what is their current load?
Who programs, and what happens when that person is away?
Which operations on my part are done in this building?
What do you decline, and why?

Question five is the most informative on the list. A shop that declines nothing is telling you it discovers problems after the order rather than before it.

The finishing chain

Who does your anodize, electropolish, plating and heat treatment?
How far away, what is the normal turnaround and what is the batch minimum?
What happens when a part comes back out of spec, and who pays?
Do you inspect parts when they return from the finisher, and what do you check?
Can you supply the finish certificate with the shipment?

Inspection and documentation

What inspection equipment is here, and when was it last calibrated?
Show me a first article report with the ballooned drawing.
How do you measure surface finish, and what cutoff do you use?
How do you measure flatness on a large plate, free state or constrained?
Do you keep a control plan for repeat parts?

The documentation questions are in first article inspection reports, and the measurement questions in flatness, parallelism and datums.

Cleaning, packing and handling

Walk me through cleaning a part that goes into a cleanroom, step by step.
Where are parts stored between operations, and what are they stored in?
What do you pack in, and who decides the packing level?

If the answer to sixteen is a single sentence, the shop cleans parts rather than following a process. The difference is in what cleanroom machining actually requires.

Commercial and continuity

Have you shipped export orders on your own documents, and to where?
Who is my contact when something goes wrong at ten at night, and in what language?

Answers that should worry you

“We can do everything” with no examples
A cleanroom claim with no ISO class, no particle count and no procedure
A quote returned in under an hour on a drawing with finish, flatness and packing requirements
Sample parts that are better than anything the shop could repeat in a lot of fifty
Certificates that cannot be produced for a job they already delivered

After the audit

Run a paid pilot lot at the real quantity and measure delivery as well as dimensions. A shop that hits tolerance and misses dates twice is not a supplier, it is a rework queue. If the pilot works, write down what made it work and use the same document for the second source.

If you would rather skip the search and go straight to shops that have already answered these questions, send the RFQ and we will match on them.

Frequently asked questions

Can this be done remotely?

Partly. Documents, certificates, reports and photographs travel. What does not travel is the state of the shop floor, how parts are stored between operations and whether the cleaning area is what the slide says it is. Do the paperwork remotely, then visit before a first production order.

What is the single most useful question?

Ask to see a first article report from a job like yours, with the ballooned drawing next to it. It shows the measurement capability, the documentation discipline and the kind of work the shop actually does, all in one document.

How long should an audit take?

Half a day for a small shop, a full day if finishing and inspection are being reviewed properly. Longer visits usually mean nobody prepared.

Need a quote for this part?

Send the drawing. We match you with up to 3 shops in Vietnam and reply within 24 business hours.

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