Mechanical assembly
One-stop precision sheet metal manufacturing
One-stop OEM partner for Mechanical assembly: MetlTek runs precision sheet metal, mechanical assembly and complete unit delivery from a single plant in Kunshan, China. Founded in 2001, the factory runs three laser cutting machines (a Trumpf 3030 plus two Hongshan machines, the largest 6000 x 2540 mm), a 6.5 m CNC gantry machining center, a Salvagnini P2Lean bending center, Panasonic and Fronius welding robots and an 8 m rail-mounted welding cell. Finished goods ship to industrial customers across Europe and North America.
Every order starts from your drawings. We quote from STEP, DWG or DXF files, build a first-article sample, then run series production on the same line. Typical sheet thickness runs from 0.5 mm to 12 mm in cold-rolled steel, galvanised steel, stainless steel 304/316 and aluminium.
What you get when you order
Three commitments we are judged on by every customer, on every order.
Round-the-clock response
Send drawings at any hour — an engineer replies within one working day, not an automated ticket.
Factory-direct pricing
No trading layer in between. You buy from the plant in Kunshan that actually cuts, bends and welds the parts.
Delivery you can plan around
Committed lead times, serialised inspection records and export packing that survives ocean freight.
Typical specifications
| Material | Cold-rolled steel DC01, galvanised steel, stainless steel 304 / 316, aluminium |
|---|---|
| Sheet thickness | 0.8 – 6.0 mm |
| Tolerance | ± 0.05 mm (laser cut, all machines), ± 0.25° (Salvagnini / TRUMPF bending), ± 0.3 – 0.5° (conventional brakes) |
| Surface finish | Powder coating to RAL (2 automatic lines), zinc plating, brushed or polished |
| Minimum order | 1 piece for prototypes, series from 50 pieces |
| Lead time | Sample 7–10 working days · series 3–5 weeks |
Production Equipment
Inspection & information systems
| Array | ||
|---|---|---|
| Inspecvision optical vision measuring (UK) | 1 | full-surface fast inspection · automatic deviation report |
| ERP full-process management | 1 | sales · purchasing · production · QC · stock · finance |
| MES shop-floor visibility | 1 | real-time progress · data capture · alerts |
All parameters match the factory nameplates and can be verified during customer audits.
Assembly is where a kit becomes a product
Sheet metal assembly is the discipline of taking a set of formed parts, giving each one a definite position relative to the others, and fixing it there so the result matches the drawing. It sounds trivial and it is not. The process runs from locating and fixturing through welding or riveting, correction after welding, finishing and final inspection — and the order in which those steps happen decides how much distortion there is to correct. A sequence chosen badly means chasing flatness and squareness on finished parts. Chosen well, the parts hold each other in position and the corrections are small. There is no single correct sequence either: frame size, batch size, tooling, material spring-back and the skill on the bench all move the answer. One structural point is worth knowing early — unlike plastic parts, most sheet metal has almost no elasticity, spring grades such as SUS301 being the exception, so an assembly cannot rely on snap-fit and detent alone.
What we deliver at each level
| Mechanical assembly | hardware insertion, riveting, threaded fasteners, hinge and latch fitting, gasket and seal installation, and dimensional check against the drawing |
|---|---|
| Mechanical fit-up | enclosure squareness, door and gasket seating, hinge and lock alignment, and cut-out position against the drawing, recorded against the work order |
| Dimensional verification | measured clearance and gap checks, seal compression on rated enclosures, and attenuation-relevant seam checks on EMI-shielded cabinets |
| Documentation | inspection report, hardware and torque records, and test results shipped with the batch |
| Packing and dispatch | protective wrap, custom foam or a wooden crate, export labelling, and palletisation matched to how the container will be loaded |
Assembly pitfalls and the controls on them
Assembly errors rarely come from one wrong move. They come from a sequence that gives a part nowhere to sit, or a check that happens after the point of no return.
Losing the datum
Once the first locating feature is buried under other parts, everything downstream is measured from whatever is convenient rather than from the drawing. Datum is set and recorded at the start, and fixtures hold it through the rest of the build.
Tolerances stacking up
Individually in-spec parts can still assemble out of position. On critical builds we measure the assembly rather than the parts, and where the stack is tight we hold the first part of the chain closer than the drawing demands.
Deformation from over-torque
Thin sheet and soft alloys deform long before a fastener is tight. Torque values are specified rather than judged, and hardware is pressed in-line so fasteners do not have to pull a panel into place.
A snap-fit that cannot work
Designed as though sheet metal behaves like plastic. Where a closure has to be tool-less we use a formed spring feature or a discrete catch, and prove it on the first sample rather than at volume.
Contamination inside a sealed enclosure
Swarf and grinding dust sealed into a cabinet will find electronics eventually. Cleaning happens before sealing, and sealing happens after the last metal-cutting operation.
Missing hardware at final inspection
Boards are built to a parts list and signed off against it, so an omission is caught at the station where it happens rather than by the customer.
What ships as a tested unit
- Control cabinets and operator panels delivered assembled and tested
- Automation equipment frames with hardware, guarding and cabling installed
- Energy and telecom cabinets sealed and functionally checked before dispatch
- Medical and instrument housings where cleanliness and cosmetic standard both matter
- Complete lines where sheet metal, mechanical assembly and dimensional check are one purchase order
Built for buyers who audit their supply chain
Four things that decide whether a metal enclosure project lands on time and on budget.
Tolerances we can hold
±0.1 mm on laser-cut features and ±0.3 mm on formed parts, verified before dispatch.
Quality you can audit
ISO 9001 processes, first-article inspection and a measurement report with every series batch.
One supplier, five processes
Cutting, bending, welding, coating and mechanical assembly under one roof — no hand-offs between vendors.
Built for export
Export-grade packing, customs documentation and container loading planned for Europe and North America.
From your drawing to a delivered container
A four-step process, with a defined deliverable and a defined owner at each step.
Send drawings
STEP, DWG, DXF or PDF — tell us material, surface finish and quantity.
Engineering review
We flag manufacturability issues and return a quotation with lead time and tooling cost.
Sample and approval
A first-article sample in 7–10 working days for dimensional and finish sign-off.
Series production and shipping
Batch production with inspection records, then export packing and container loading.
Product lines
Frequently asked questions
What is the minimum order quantity?
There is no fixed MOQ. Prototypes and small batches from one piece are accepted, and unit prices fall as volume grows. One-off tooling cost is quoted separately.
Can you work from our drawings and keep them confidential?
Yes. We regularly work under NDA and produce strictly to customer drawings. Files stay on an internal server and are never shared with third parties.
How long does production take after the sample is approved?
A first-article sample is typically ready in 7–10 working days, and series production runs in 3–5 weeks depending on quantity and surface finish.
Send your drawings and quantity — an engineer, not a sales script, comes back with a quotation covering material, tooling, surface finish and lead time.
Send your drawings and quantity — you will get a quotation with lead time, not a sales script.