The Complete Sheet Metal Fabrication Process for Self-Service Kiosk Enclosures

Vending machines at the mall. Registration kiosks at hospitals. Ticket machines at train stations. Most people never think about what it takes to build the metal box around them — but for buyers and product managers, understanding the process is where the real value lives.

We run a sheet metal fabrication factory in Hangzhou, China, specializing in enclosures for self-service terminals. This is our entire process, step by step — including the details that separate a cheap enclosure from one that still looks new after five years.

Step 0: Drawing Review — The Most Overlooked Step

Most customers think fabrication is just "make what the drawing says." In reality, drawing review is where projects are won or lost.

Before we cut a single sheet, we verify:

• Material thickness — 1.0–1.5mm cold-rolled steel for most enclosures, thicker for load-bearing areas
• Bend radius — too small and the material cracks
• Tolerances — ±0.1mm on mating surfaces, ±0.3mm on cosmetic surfaces
• Ventilation and cable pass-through holes are accounted for

Getting this right upfront saves half the trouble downstream. We offer free process review on every customer drawing — it looks like extra work, but it saves real money in rework.

Step 1: Cutting — Precision Is the Skeleton

A laser cutting machine cuts the sheet into shape, holding ±0.5mm tolerance.

Here's a detail most outsiders don't know: you must calculate the "unfolded dimensions" before cutting. Steel stretches when bent, so the bend allowance has to be deducted in advance. Get this wrong and the whole batch is scrap.

Step 2: Bending — Where Masters Separate from Amateurs

CNC press brakes fold the flat sheet into a 3D structure. A typical vending machine enclosure needs 20–60 bends.

Two classic challenges:

1. Springback. Steel "springs back" after bending, so the angle must be over-compensated in the program. The compensation depends on material thickness, grade, and tooling — it's pure operator experience.

2. Cumulative error. Each bend carries ±0.1mm error. If every bend drifts slightly, you can end up a full millimeter off by the last bend — and the door won't close.

That's why good factories run "same machine, same tooling, same material batch" for each job. Sheet metal isn't fully automated — the feel of an experienced operator is still the core competitive advantage.

Step 3: Welding — Where Appearance Is Decided

Bent parts are assembled and joined with spot welding or TIG welding.

Weld quality determines the finished grade:

• Welds must be solid — weak welds compromise structural strength (a safety item)
• Seams must be flat — grinding quality directly affects the final coating
• Thin sheets deform easily — we use fixtures and skip-welding techniques

After welding: grinding, filling, and a weld inspection (tapping + visual check for weak welds) before surface treatment.

Step 4: Surface Treatment — The Real Reason Quotes Differ by 2×

Pre-treatment is mandatory: degreasing → rust removal → phosphating. Skip or shortcut this, and the paint will bubble and peel within a year.

Two main coating options:

• Powder coating (electrostatic + oven curing) — tough and scratch-resistant, the default for public equipment
• Liquid paint — more color options, multi-color and gradient finishes

Step 5: Silk-Screen / Labeling — Details Make the Product

Logos, instructions, and warning labels are applied by silk-screen or film.

Looks simple, but 1mm off-center makes the whole machine look cheap. We use positioning fixtures plus first-article inspection so every unit is identical.

Step 6: Assembly & Inspection — The Final Gate

The enclosure is the "house"; the display, control unit, cash box, and locks are the "furniture" that moves in.

Then the full inspection checklist:

• ✔ Door/lock open-close test (smooth, no noise)
• ✔ Cable routing check (organized, secured, no pinched wires)
• ✔ Ground resistance test (safety item — always)
• ✔ Burn-in test (powered run to expose early failures)
• ✔ Final cosmetic inspection (scratches, color mismatch, gaps)

Pass everything, then it's packaged and shipped.

The Honest Summary

A self-service terminal enclosure typically takes 5–10 working days from drawing to finished product.

On the surface, it's a "metal box." In reality, every step is stacked with detail. That's why the same enclosure can be quoted at double the price by different factories — and why a cheap one rusts in a year while a good one still looks new after five or six.