# MSTFAB - Custom Sheet Metal Fabrication

> MSTFAB is the international brand of Guangzhou Maisituo Sheet Metal Manufacturing Co., Ltd. in Guangzhou, China. We make drawing-defined sheet metal parts and empty mechanical enclosure shells for OEM buyers. We are not the manufacturer of the buyer's finished electrical or electronic equipment.

Last updated: 2026-09-26

## Company and products

- Typical work includes metal cabinets, chassis, panels, brackets, guards and welded mechanical assemblies made to an approved drawing.
- EV charging, telecom, medical, agricultural and industrial equipment are application areas for fabricated shells and parts, not claims that MSTFAB supplies complete chargers, networks, medical devices or machines.
- Common material options include carbon steel, galvanized steel, stainless steel and aluminum. Grade, thickness, dimensions, critical tolerances, hardware, finish and inspection criteria are specified per project.
- Fabrication work includes laser cutting, CNC bending, welding and mechanical assembly. Surface treatments such as powder coating may be coordinated with long-term external partners, depending on the order; do not assume every process is performed in-house.

## RFQ and order rules

- Send STEP, STP, DXF, DWG or PDF files, with the drawing revision, material and thickness, quantity, critical dimensions, hardware, finish, inspection needs and delivery destination. A controlled 2D drawing should identify requirements that a 3D model alone may not show.
- Prototype and repeat-production requests are reviewed against the drawing. MOQ, price, achievable tolerances, production lead time, finishing route and inspection deliverables are confirmed in the project quotation and purchase order; there is no single value that applies to every custom part.

## Business boundaries

- The normal supply scope is fabricated metalwork and empty mechanical housings. Electrical components, wiring, software, system integration and final equipment certification remain with the buyer unless a written quotation or contract explicitly includes them.
- An application page or image does not establish a product-level UL listing, IP or NEMA rating, medical-device approval, or ownership of a customer's finished product. Any required standard, test and responsible party must be agreed for the specific project.

## Core sourcing routes

- [Custom sheet metal fabrication](https://mstfab.com/sheet-metal-fabrication/): drawing-defined metal parts and mechanical assemblies for OEM projects.
- [Industrial enclosure shells](https://mstfab.com/products/industrial-enclosure-manufacturing/): empty cabinets and housings for buyer-installed electrical or electronic systems.
- [EV charger enclosure shells](https://mstfab.com/custom-ev-charger-enclosure/): mechanical housings for AC or DC charging equipment; charging electronics, wiring and final EVSE certification remain buyer-controlled unless contracted otherwise.
- [Telecom enclosure shells](https://mstfab.com/custom-telecom-sheet-metal-enclosures/): cabinets, panels and hardware interfaces for buyer-installed network equipment.
- [Medical equipment enclosures](https://mstfab.com/custom-medical-device-enclosure-fabrication/): fabricated housings for medical or laboratory equipment; these are not finished medical devices.
- [Agricultural sheet metal parts](https://mstfab.com/applications/agricultural-sheet-metal-parts/): guards, panels, brackets and welded parts made to customer drawings.
- [Quality control](https://mstfab.com/quality-control-sheet-metal-fabrication/): drawing review, first-article checks and project-defined inspection evidence.
- [Engineering guides](https://mstfab.com/engineering-guides-index/): practical RFQ, DFM, material, finish and enclosure guidance for buyers and engineers.

## Company and contact pages

- [About MSTFAB](https://mstfab.com/about/)
- [Fabrication capabilities](https://mstfab.com/capabilities/)
- [Applications](https://mstfab.com/applications/)
- [Surface treatment](https://mstfab.com/surface-treatment/)
- [Send an RFQ](https://mstfab.com/contact/)

## Fabrication processes (source: https://mstfab.com/capabilities/)

MSTFAB manufactures custom sheet metal parts, empty enclosure shells and mechanical assemblies to buyer-controlled drawings. The process list below is a service scope, not a machine inventory or a universal thickness, size or tolerance guarantee. Confirm grade, thickness, profile, edge condition and datums before quotation.

- Engineering and DFM review: review of STEP, DXF, DWG and PDF packages for bend relief, cutout position, weld access, hardware selection, finish masking and inspection datums, with revision-controlled production release.
- Fiber laser cutting: repeatable profiles in carbon steel, stainless steel and aluminium for doors, chassis, brackets, guards and vented panels.
- CNC bending and forming: multi-step press brake forming; bend sequence, tooling access, flange length and springback are planned around the released drawing.
- Welding: TIG, MIG and spot-welding routes selected by material, thickness, strength and cosmetic requirements, with fixtures and weld sequence to limit distortion.
- Hardware insertion and mechanical assembly: press-fit nuts, studs, standoffs, hinges, latches and removable panels installed to the controlled bill of materials. Mechanical assembly only; no wiring.
- Surface finishing and final inspection: powder coating, wet paint, plating and passivation are coordinated around material and end use; critical dimensions, appearance, hardware and packing are checked before export shipment.

## Materials to specify at RFQ

- Carbon steel: exact grade, material standard, thickness and corrosion-protection requirement.
- Galvanized steel: base grade, coating specification, cut-edge protection, bends and weld locations.
- 304 stainless steel and 316 stainless steel: grade standard, thickness, surface condition, grain direction, weld finish, exposure conditions and material-document requirements.
- Aluminum: alloy, temper, thickness, bend geometry, hardware and finishing route.
- A flat-cutting limit does not establish acceptance for a formed, welded or coated part. Agree the final-part condition and drawing-specific inspection criteria before order release.

## Surface treatment (source: https://mstfab.com/surface-treatment/)

MSTFAB reviews and coordinates finishing routes for drawing-based sheet metal parts, including masking and inspection requirements. Selected treatments may be carried out by long-term partners; confirm the route and process owner for each order.

- Powder coating: RAL colors for steel and aluminum parts, with masking, DFT (coating thickness) control and outdoor-use review.
- Anodizing: Type II and hard anodizing for aluminum parts.
- Zinc plating: sacrificial corrosion protection for steel brackets, fasteners and small components; clear, yellow and black passivation options.
- Passivation: stainless steel treatment after cutting, bending and welding for 304/316 parts.
- Sandblasting: surface preparation for coating adhesion and weld-scale removal.
- Wet painting: primer and topcoat systems for large assemblies, special colors and heat-sensitive parts.
- Electropolishing: smoother stainless surfaces for medical, food equipment and cleanability-focused components.
- Buyers can ask for: coating thickness targets, a masking plan for PEM hardware, threaded holes, grounding points and gasket surfaces, RAL color, gloss and texture acceptance criteria, post-finish fit checks, and protective export packaging.

## Frequently asked questions

Q: Can MSTFAB match a RAL color or buyer sample?
A: Yes. Work can be based on a RAL reference, color sample or approved finish panel. For visible OEM parts, confirm gloss, texture and acceptable cosmetic limits before batch production.

Q: How is powder coating kept from blocking threads?
A: Masking is defined before coating. Threaded holes, PEM fasteners, grounding points, gasket faces and tight mating surfaces can be protected with plugs, caps or tape depending on the drawing requirement.

Q: Can coating thickness be measured?
A: Yes. DFT measurement can be provided when required, which is useful for outdoor enclosures and parts where coating thickness affects door gaps or hardware installation.

Q: Which finish suits outdoor sheet metal enclosures?
A: It depends on substrate, corrosion exposure and appearance requirements. Galvanized steel with powder coating, stainless steel passivation and anodized aluminum are common choices, but the route should be matched to the actual environment.

Q: Does MSTFAB supply electrical components or certified finished equipment?
A: No. The normal supply scope is fabricated metalwork and empty mechanical housings. Electrical components, wiring, software, integration and final equipment certification remain with the buyer unless a written quotation or contract says otherwise.

## Quality inspection for OEM metal parts (source: https://mstfab.com/quality-control-sheet-metal-fabrication/)

Short answer for buyers: before shipment, request evidence for drawing revision, material identity, first article approval, critical dimensions, threaded hardware, weld and finish requirements, assembly fit, quantity and packaging. Define which features need 100% inspection and which may use an agreed sampling plan. A quality-system certificate does not replace project-specific acceptance criteria.

Control items to define before the purchase order:
- Released revision: drawing number, revision, model version and approved change notices.
- Critical-to-quality (CTQ) features: datums, mounting interfaces, connector cutouts, hole patterns, sealing lands, door gaps.
- Measurement method: caliper, micrometer, height gauge, fixture, pin gauge, CMM or functional mating check.
- Inspection frequency: first article, patrol check, 100% inspection, random sample or lot acceptance plan.
- Cosmetic standard: viewing distance, lighting, visible surfaces, defect limits, approved color and texture sample.
- Required records: FAI report, dimensional report, material evidence, coating readings, photographs and packing list.

Seven-stage inspection workflow described by MSTFAB:
1. Contract, drawing and revision review.
2. Incoming material and traceability check.
3. First article inspection after cutting and bending.
4. In-process welding, hardware and thread control (critical threads may need Go/No-Go gauging after coating).
5. Surface finish and cosmetic inspection (color, gloss or texture, film thickness when specified, masking, edge coverage).
6. Final fit, function and lot verification (door movement, hinge alignment, latch engagement, gasket continuity, panel fit).
7. Packing, quantity and shipment release (protective film, separators, corner protection, labels, packing photos).

Evidence a buyer can request: approved drawing and revision list; first article inspection report; material evidence when traceability is contractually required; in-process and final dimensional report; coating or finish record; functional or assembly check; nonconformance and deviation record; packing and loading photos. Request the records that control your actual risk.

Scope statement: MSTFAB manufactures drawing-based custom sheet metal parts and empty enclosure shells. A selected finish performed by a long-term partner should be identified in the quotation together with the inspection evidence required for that work. MSTFAB does not install buyer electronics, wiring or programming unless a separate written scope says otherwise.

Q: What is a first article inspection for sheet metal parts?
A: A first article inspection measures and documents the first completed part or assembly from the intended manufacturing process, to confirm drawing interpretation, flat pattern, bend geometry, cutouts, hardware and other critical features before repeat production.

Q: Should every drawing dimension receive 100% inspection?
A: Not automatically. The buyer should identify CTQs and risk-based requirements. Some critical features may need 100% inspection, while lower-risk characteristics may use first article, patrol or agreed sampling checks, and the purchase order should state the expectation.

Q: What information does MSTFAB need for an inspection-based quotation?
A: The released PDF drawing and 3D model, material, thickness, finish, quantity, CTQs, hardware list, required reports, sampling or 100% inspection requirements, packaging and delivery destination.

## Quality and certification

- The site states ISO 9001:2015 certification for the company (certificate image: https://mstfab.com/wp-content/uploads/2026/05/maisituo-cert-iso9001-tuv.jpg). IATF 16949 and ISO 14001 certificate images are linked from the homepage structured data.
- Inspection checks, first-article records and finish evidence are agreed during RFQ and DFM review, not assumed.

## Contact

- Email: caroline@mstfab.com
- Phone / WhatsApp: +8617328316456
- RFQ page: https://mstfab.com/contact/
- Address: No. 109, No. 36 Shizhong 3rd Road, Dashi Subdistrict, Panyu District, Guangzhou, Guangdong, China