Sanitary stainless fabrication · Churnbrook & the butter country · Est. 2009

Welds you could eat off. In fact, you will.

Mirrorseam fabricates food-grade stainless for the creameries, breweries and kitchens of the butter country — 316L tube purged with argon to a bright internal bead, orbital welds on every product line, corners polished to 180 grit and passivated to ASTM A967. The inspector wipes, the swab comes back clean, and the line runs Monday.

Welds you could eat off. In fact, you will.
Ra 20
mirror polish on every product-contact surface, in microinches
99.99%
argon purge purity behind every orbital weld we close
316L
the only product-contact steel this shop buys
0
failed swabs in fourteen years of sanitary work

The works on Dairy Lane

Two rooms, one standard

The cutting, blasting and pipe-threading happen in the dirty room; the tube bench, the polisher and the passivation tanks live behind a wall it is forbidden to carry swarf through. Sanitary work is mostly discipline about rooms — which is why a fabricator with one open bay keeps selling you a chipped rail, and why ours has a doorway with rules.

The sanitary card

Rates from last quarter’s creamery and brewery work. Every number includes the purge gas, the polish and the passivation certificate — the things a sanitary job cannot skip are not extras.

Sanitary tube rail — fabricated & set$210–265 / linear ft

316L, orbital-welded under argon, pitched to your drains

Process tanks & hopper conesby drawing, from $3,800

Dished heads, CIP spray balls fitted, crevice-free corners

Coved floor & wall panelling$96 / sq ft

Dairy board, coved internal corners, sealed to the wall

Washdown guards & shrouds$120 / linear ft

304 economy line where product never touches

On-site TIG repair — sanitary$145 / hr

Purged field welds, re-passivated in place

Passivation & swab certification$460

ASTM A967, documented, per visit

The weld map

From the plant walk to the clean swab

  1. Day 1

    The walk, with your QA

    We measure in the plant with the quality lead beside us — slopes, drains, dead legs flagged on the spot, and a photograph of every surface the rail will meet. Sanitary work is decided in the first hour on the floor.

  2. Week 1

    The isometric & the weld map

    A drawing where every joint carries a number, every purge point is marked, and the slope is called out per run in writing. You approve the map, not just the price — the inspector will ask for it eventually, so it may as well exist early.

  3. Weeks 2–3

    The clean room bench

    Tube cut and faced square, then orbital-welded under 99.99% argon. Internal beads are inspected with a borescope before a joint is closed; anything sugared or shadowed is cut out and re-done, never cosmetically blended.

  4. Install

    Set, passivate, swab

    Rail set to the laser slope, field joints purged and welded, the whole contact surface passivated to ASTM A967 and swipe-tested with your QA watching. The certificate is signed on your floor, not mailed later.

The Dairy Lane works

Why the dirty room matters

Carbon steel dust lands on stainless and rusts there later — it is the oldest failure in food plants and it is never the welder’s fault, until it is. Our split rooms mean the torch that welds your rail has never been near a grit blaster. It costs us a wall; it saves you a recall.

The swab is the shipping label

If a Mirrorseam contact surface fails a swipe test in its first year, the re-passivation, the re-test and the visit are ours. In fourteen years it has not happened once — the wall, the purge discipline and the borescope are why.

The butter country, 2025 — 2026

Recent food-grade work

Six lines from the clean room this year. If a caption does not name a finish, assume Ra 20 and a certificate in the crate.

Churnbrook Creamery
Churnbrook Creamery — 40 m of purged rail, pitched to one drain
Two Rivers Brewing
Two Rivers Brewing — bright-tank platform, coved floor
The Ondley Bakehouse
The Ondley Bakehouse — washdown guards, 304 economy line
Halls Ferry Cheese
Halls Ferry Cheese — hopper cones, CIP spray balls fitted
Gorsel Milk Depot
Gorsel Milk Depot — tanker rail, set on the night shift
Marlden Kitchens
Marlden Kitchens — pass tables, orbital corners
Our old rail had a weld the inspector could hide a cotton swab inside of, and did, twice. Mirrorseam showed me a borescope photo of the INSIDE of their weld — bright, flat, no shadow — before I signed anything. The line passed its swab the first Tuesday and every Tuesday since. I did not know fabrication could be boring. It turns out boring is the compliment.
Dorit Kessel — QA lead, Churnbrook Creamery

Before the walk-through

Fair questions

The five every plant manager asks on the first call. The shop line at the bottom of the page answers any shift, including the one at 3 a.m. when the CIP loop alarms.

Why 316L and not 304 everywhere?

The two percent molybdenum in 316L is what stands up to brine, chloride cleaners and the salt a cheese plant breathes. 304 is legitimate steel and we use it — but only where product never touches and no hose ever points. The drawing marks which is which, per surface.

What is a dead leg, and why do you keep saying it?

A stub of tube that holds product without flow — a culture hotel with a doorman. We design runs so every branch drains, and we flag any your existing plant forces on us, in writing, before the weld map is approved.

Can you weld inside a running plant?

Yes — night shifts, containment tents, hot-work permits we file ourselves, and a purge box so the argon stays where the joint is. Plants do not stop for fabricators; fabricators work around the cleaning schedule.

Powder-coat on my frames?

Never on a product-contact surface — paint is a foreign object waiting to chip. Legs and non-contact frames get a two-pack epoxy in your colour, and the drawing lists every painted piece so the inspector never has to ask.

How long is my line down?

Measured on a Friday, fabricated in two to three weeks, and installed in one planned shift — field joints purged, passivated and swabbed before your QA goes home. The line is down for hours, not weeks.

Plant walk-throughs on any shift, estimates inside two days · (555) 014-2210 · shop@mirrorseam.example

Send the line drawing — or the napkin version

A sketch of the run, the drains it must fall to, and what the plant makes. The weld map and the fixed quote follow the walk-through, and the swab certificate follows the work. shop@mirrorseam.example