Two hundred aluminum housings came back from anodize in March with rack marks on the mounting face. Type II clear, nothing exotic. The customer had circled that face on the print: cosmetic, no witness marks. Eleven days to the ship date.
I called the anodizer at 7:15 the next morning. He was decent about it. Stripped and re-ran the lot on his dime, had them back in six days, and we shipped on time. That’s not the part I remember. What I remember is the certificate framed in his lobby the day I toured that shop, which told me nothing about whether somebody would rack two hundred parts wrong.
I own outside processing here. Anodize, plating, passivation, powder coat, black oxide, heat treat. I pick who gets the work and I’m the one calling when a lot’s late, so I’ve collected opinions.
We don’t run tanks, and I don’t want to
Everything we machine, we machine here. 3, 4 and 5-axis milling, turning, CMM and vision inspection under our own roof. No tanks, no booth, no furnace, and I don’t want any. Those are chemistry businesses, run by people who’ve done nothing else for twenty years. Handing finishing to a shop that only does finishing is the right answer. Nobody’s settling.
But a finished part is our machining plus a process somebody else controlled. If the coating comes back out of thickness range, or the lot shows up nine days late, the customer doesn’t file that under vendor problem. It’s ours. They’re right.
The certificate is a floor
I ask for certifications and I read them. Registration to a quality standard, plus whatever process approvals the job calls for. Aerospace and medical make those non-negotiable, so if a shop doesn’t have them it’s a short call.
But a certificate says a documented system existed the day an auditor walked the floor. It says nothing about what the line lead did at 4:40 on a Friday with racks backed up.
Two things make one worth reading. The scope statement is first, the only part of the document carrying information. “Anodizing” isn’t a scope. Type II and Type III sulfuric on aluminum, class and thickness ranges written out, is a scope. I’ve had a shop send a gorgeous certificate that didn’t cover the process I’d called about. Twice. Same shop. Second time I’m fairly sure he knew.
Second is whether they’ll talk about their own nonconformances. I ask what their last finding was and what changed because of it. A shop with a real system answers in a sentence. A shop whose system lives in a binder gets vague, and the vagueness is the data point I wanted.
The four things I actually keep
On-time delivery, measured when my dock takes possession. Not when the vendor ships. Not when a carrier scans a pickup. That’s the vendor’s convenience, and it forgives transit and Friday handoffs that sit in a warehouse until Monday. I score against the date they put in writing when they took the order. If it moves later, I keep both and score the first one. This irritates people. I’ve made my peace with it.
First-pass yield, the number nobody volunteers. What fraction came back conforming, no rework, no sort, no second trip through the tank. A vendor who returns 100 pieces and reworks 12 after my inspection didn’t deliver 100 good pieces. He delivered 88 and a second lead time I hadn’t planned for. The conformance paperwork gets written after the rework, so it reads the same.
Third, whether they call me before I find out myself. Nobody has a clean quarter every quarter, so when a vendor has never once called with bad news, all I’ve learned is that his bad news shows up on my dock instead of over the phone. A voicemail saying your rack came out light, we’re stripping and re-running, Thursday instead of Tuesday, beats a spotless record with one surprise in it.
Fourth is documentation, and this one loses people work. Do I get actual numbers or a sentence saying it conforms? Thickness readings, the lot, the date, legible, traceable to the parts in the box. On medical work I need that, and so does my customer’s auditor two years later when nobody remembers the job. Some very good finishers are sloppy here, and it’s cost them orders with me.
None of this needs software. Somebody has to decide the delivery record is evidence and keep it. Mine’s a spreadsheet, mostly.
What I don’t look at
The capability deck. They all have the same tanks, the same racks, the same photo of a clean floor with the lights on. It tells me what a shop can attempt.
The first-order price. That’s a marketing budget, not a cost structure. What matters is order twenty, after the introductory rate expires and the expedite fees start, plus the lots I had to chase. A cheap plater who slips two weeks on a medical build has already cost more than he’ll ever save me.
The salesperson, mostly. Not because salespeople lie. Their information is structurally a month old. They know what a shop can do; the scheduler knows what it’s doing this week. So I ask for the scheduler. If I can’t get five minutes with one, that tells me something too.
The first four lots
What I ask a new vendor for is short and all checkable.
- The scope statement on their certifications, plus any process approvals the work requires
- Turn time for our part family in writing, in working days, with the clock start defined
- Who I call when a lot is late, by name, and who sits above that person
- What they inspect every lot versus on request, and whether I get data or a statement of conformance
- What happens to a nonconforming lot: containment, notification, who pays for the re-run
Then a small job. Real print, real requirements, low quantity, schedule margin to absorb a miss. We inspect it hard on receipt, dimensionally too, because coatings change dimensions and people forget that.
Four lots before I’ll claim to know a vendor. I used to say three. Then a shop had a beautiful first quarter, lost its line supervisor in the spring, and I found out the expensive way.
I’ve been wrong the other direction too. A passivation house ninety minutes north had a bad August two years ago. Late three times, one lot rejected for water spotting. I had the replacement priced. Then the owner called, unprompted, and walked me through it: a rinse tank drifting out of spec, a tech covering two jobs. He told me what he’d bought and who he’d hired. I gave him another quarter, and he’s been my best vendor on on-time ever since. By the scoreboard alone I’d have dropped him.
And I dropped one that looked fine on paper. Good certificate, pleasant people, three days late twice in one quarter, both times I found out because I picked up the phone. Second time it was a customer who’d already been patient with us once.
The uncomfortable part: this takes a quarter to tell me anything, and purchasing decisions don’t wait a quarter. So it isn’t a gate. Everybody’s measured all the time, including vendors we’ve used six years, because a shop that was excellent in 2024 may have lost the person who made it so. First week of every quarter I re-read the numbers. Takes two hours.
If you buy parts from us and want to know who’s finishing them, ask me. And if a lot’s running late, you’ll hear it from me before your receiving dock works it out. That’s what I demand from my vendors. Hard to ask and not do it.
