AS9100D Machine Shop: What I Learned the Hard Way Running One

When I first heard the term AS9100D machine shop, I honestly thought it was just ISO 9001 with a fancy aerospace label slapped on it. I was wrong. Very wrong. Running an AS9100D-certified machine shop isn’t just about paperwork or passing an audit once every year. It’s a mindset shift, and it took me years of mistakes, late nights, and a few near heart attacks to really get it right.

I remember the first aerospace RFQ that landed on my desk. Tight tolerances, full traceability, first article inspection, and more acronyms than I care to remember. I almost didn’t quote it because it looked intimidating. That moment changed everything.

Why AS9100D Is a Big Deal in a Machine Shop

AS9100D isn’t optional if you want serious aerospace work. Primes and Tier 1 suppliers won’t even talk to you without it. What makes AS9100D different is risk-based thinking, product safety, and counterfeit part prevention. Those words sound simple, but living them day to day in a machine shop is another story.

I learned early that aerospace customers don’t forgive mistakes easily. One mislabeled material cert, one missing inspection record, and the job is dead. Sometimes the relationship too.

My First AS9100D Audit (and the Panic That Came With It)

I still remember my first AS9100D certification audit like it was yesterday. The auditor walked straight to the shop floor and asked an operator to explain the traveler.

The operator froze. I froze too.

That was the day I realized documentation means nothing if your people don’t understand it. Procedures can’t live in binders collecting dust. They have to live on the floor, next to the machines.

After that audit, I rewrote half our work instructions in plain language. No fluff, no corporate nonsense, just clear steps that made sense to machinists.

Documentation: The Necessary Evil of AS9100D

Let’s be honest. Documentation is where most machine shops struggle. I hated it at first. But AS9100D documentation isn’t about pleasing auditors. It’s about consistency. When you’re machining flight-critical parts, consistency keeps planes in the air.

We built:

Process flow charts for every part family
Control plans tied directly to inspection points
Clear revision control rules (no exceptions)

Once documentation matched reality, audits became easier. Still stressful, but manageable.

Material Traceability Nearly Broke Me Once

If there’s one thing AS9100D machine shops must obsess over, it’s material traceability. Early on, we had a bar of aluminum get separated from its cert. Just one bar. We spent two days trying to trace it. In the end, we scrapped it. Expensive lesson. Now every piece of material gets tagged immediately. Heat number, job number, and cert reference follow it everywhere. No shortcuts. Ever. That system saved us more times than I can count.

First Article Inspection Reports (FAIRs) Are Not Optional

FAIRs used to scare me. AS9102 felt like homework I forgot to do. But once I understood the purpose, it clicked. A First Article Inspection proves you understand the print, the process, and the risks.

We learned to:

Balloon drawings properly
Tie every dimension to a measurement result
Verify material, processes, and specs upfront

Doing FAIRs correctly reduced rework later. That alone made them worth the effort.

Training People Was Harder Than Buying New Machines

Buying a new CNC is easy. Training people to think aerospace is hard. AS9100D requires competency, not just experience. That forced me to stop assuming people “just knew” things.

We started tracking:

Machine-specific training
Inspection training
Quality system awareness

Some folks resisted at first. Over time, most appreciated knowing exactly what was expected. Fewer surprises, less blame.

Risk-Based Thinking Changed How We Quote Jobs

Before AS9100D, quoting was about cycle time and material cost. After AS9100D, risk entered the equation.

We ask questions now:

Is this tolerance realistic for our process?
Do we control special processes properly?
What happens if this part fails in service?

Sometimes we walk away from jobs. That hurt at first. But it saved us from disasters later.

Counterfeit Parts Are a Real Threat

I used to think counterfeit parts were someone else’s problem. Not anymore. AS9100D made us verify suppliers more carefully. Approved supplier lists became serious business.

We now:

Audit key suppliers
Verify cert authenticity
Track supplier performance

It’s extra work, sure. But it protects everyone downstream.

Calibration Nearly Sank an Audit Once

This one still stings. A gauge was overdue for calibration by three days. Three. Days.

The auditor caught it instantly.

That taught me that AS9100D doesn’t care about excuses. Systems must work even when people forget. We implemented automatic reminders and visual tags after that.

Problem solved, stress reduced.

Process Control Is Where AS9100D Really Lives

If you want AS9100D to work, focus on process control.

We started using:

In-process inspection checkpoints
SPC on critical dimensions
Tool life tracking

Scrap went down. Predictability went up. The shop ran smoother.

That’s when I stopped seeing AS9100D as a burden and started seeing it as a tool.

Nonconformance Reports Aren’t the Enemy

I used to dread NCRs. They felt like failure. Now I see them as feedback. AS9100D forces you to document problems, investigate root cause, and prevent recurrence. We learned that ignoring small issues leads to big ones. Writing an NCR early often saved a customer relationship.

Management Commitment Is Not Just a Checkbox

Auditors always ask about management commitment. I used to give textbook answers. The truth is, commitment shows up when production is behind schedule and quality still comes first. That’s hard. I messed that up more than once. Over time, I learned that cutting corners always costs more later. Always.

Continuous Improvement Is Slower Than People Think

AS9100D pushes continuous improvement, but it’s not flashy.

It’s small changes:

Better fixturing
Clearer travelers
Smarter inspection plans

Some improvements took months to show results. Patience was required, and yeah, I struggled with that.

Why Customers Trust an AS9100D Machine Shop

Customers trust AS9100D machine shops because the system reduces uncertainty.

They know:

Processes are controlled
Parts are traceable
Problems are documented

That trust leads to repeat work. That’s where the real value is.

Mistakes I’d Avoid If I Started Over

If I could start over, I would:

Involve machinists earlier in procedure writing
Invest in training sooner
Not rush certification just to win work

AS9100D isn’t something you “get.” It’s something you live with daily.

Is AS9100D Worth It for a Machine Shop?

For aerospace work, yes. Without question. It’s expensive, frustrating, and exhausting at times. But it forces discipline, clarity, and professionalism. My shop became better because of AS9100D, not in spite of it.

Final Thoughts on Running an AS9100D Machine Shop

Running an AS9100D machine shop taught me humility. It showed me how much I didn’t know. It also gave me confidence. When a difficult aerospace job comes in now, I don’t panic. I trust the system. If you’re thinking about AS9100D, know this: it will challenge you. It will expose weaknesses. And if you let it, it will make your shop stronger.