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CUSTOM METAL & PLASTIC COMPONENTS · DONGGUAN, CHINA
Precision metal and plastic components. From your first prototype to repeat production.
TOPS Precision supports engineering teams worldwide with CNC machining, die casting, sheet metal fabrication and plastic injection molding under one manufacturing partner.
Upload STEP / STP / IGES / PDF / DWG files
Engineering review and DFM support available.
One partner. Four manufacturing routes.
Choose the process around geometry, tolerance, material, quantity and total program cost. Start with the capability you need—or send your drawings for an engineering review.
Precision milling and turning for complex metal and plastic parts, prototypes, fixtures and end-use components.
Repeat production of aluminum, zinc and magnesium components when geometry, alloy and volume justify tooling.
Cut, bent and formed metal parts for enclosures, frames, covers and assemblies.
Tooling and thermoplastic molding for engineering validation, pilot builds and repeat production.
TOPS Precision is a custom precision manufacturing company in Dongguan, China, providing CNC machining, die casting, sheet metal fabrication and plastic injection molding for metal and plastic components from prototype through production.
*The ±0.005 mm capability is feature- and process-specific. Critical dimensions are confirmed during quotation; it is not a blanket tolerance for cast, formed or molded parts.
The facts, in one place
| Capability | TOPS Manufacturing Range |
|---|---|
| Manufacturing processes | CNC machining, die casting, sheet metal fabrication and plastic injection molding |
| CNC axes and methods | 3-axis, 4-axis and 5-axis machining; turning, mill-turn, EDM and grinding subject to feature review |
| CNC tolerance | Down to ±0.005 mm for suitable features, geometry and materials; acceptance criteria agreed before manufacture |
| Production volume | Prototype, pilot build, low-volume batch and repeat production; quantities quoted per project |
| Metals | Aluminum, stainless steel, steel, brass, copper, titanium and selected advanced alloys |
| Plastics | ABS, PC, POM, PEEK, Nylon, PP, PMMA, PTFE and other suitable grades |
| Inspection | CMM, optical measurement, micrometers and gauges; XRF for suitable alloy-composition screening |
| Documentation | FAI, dimensional reports, material certificates, RoHS documentation and CoC as specified |
| Surface finishing | Anodizing, hard anodizing, plating, passivation, powder coating, electropolishing and polishing |
| Secondary operations | Deburring, heat treatment, hardware installation and assembly operations as agreed |
| Quality system | ISO 9001:2015 |
| File formats | STEP, STP, IGES, X_T, STL, DWG, DXF and PDF |
Material grades, part envelope, tooling scope, lead time and inspection coverage are confirmed against your drawing and order requirements.
Keep the program moving
Your manufacturing route can evolve as a design matures. We review what must stay consistent—and what should change—between development, pilot builds and repeat production.
Evaluate fit, assembly and function before committing to production tooling.
Manufacturing route: CNC machining and suitable rapid manufacturing routes. Test material and process should reflect the intended evaluation.
Build the quantity you need while designs, demand or production tooling are still developing.
Manufacturing route: CNC machining, soft tooling where suitable and other project-specific methods. Tooling investment is assessed against unit cost.
Move approved designs into a repeatable manufacturing program.
Manufacturing route: Die casting, injection molding or optimized machining, selected around the part, annual demand and approved quality plan.
Geometry. Material. Quantity. Cost.
Engineers review geometry, tolerances, material, annual quantity, surface requirements and target cost before recommending a manufacturing route.
| Your requirement | Process to evaluate | Why it may fit |
|---|---|---|
| Complex precision metal prototype | CNC machining | Limited tooling investment; direct access to 3D geometry and drawing-defined features. |
| Tight-tolerance low-volume parts | CNC machining | Critical features can be machined and inspected individually. |
| Repeat aluminum housing | Die casting + secondary machining | Evaluate alloy, draft, wall thickness, tool cost and volume. Machine critical interfaces after casting. |
| Thin metal enclosure | Sheet metal fabrication | Use cut patterns, bends, welds and hardware to create a functional assembly. |
| Repeat thermoplastic enclosure | Injection molding | Review resin, uniform walls, draft, gates, shrinkage and tooling investment. |
| Cylindrical or rotational component | CNC turning / mill-turn | Rotational features suit turning; cross-features may require additional milling. |
| Complex multi-sided geometry | 5-axis CNC machining | Can reduce setups or improve cutter access when the part and fixture support it. |
These are starting points for DFM, not automatic process assignments. Undercuts, accessible datums, wall thickness and inspection requirements may change the route.
CONTROL THE FEATURES THAT MATTER
Precision depends on part geometry, material, feature size and manufacturing method. TOPS supports tolerances down to ±0.005 mm for suitable CNC-machined features.
Critical dimensions are reviewed during quotation and verified using an agreed inspection method. Surface finishing, heat treatment and assembly conditions are considered before dimensions are finalized.
For suitable CNC features. Confirmed by drawing review.
3-, 4- and 5-axis machining, with access and workholding reviewed.
CMM, optical measurement, micrometers and gauges selected for the feature.
Dimensional reports, FAI and material certificates as specified.
Datum scheme, sampling and measurement conditions agreed before production.
Documented checks. Defined acceptance.
TOPS operates an ISO 9001:2015 quality management system. Inspection planning connects the drawing requirements to checks at each stage of manufacturing.
Tell us which dimensions are critical, which reports you need and how the parts will be used. A clear inspection plan makes acceptance criteria visible before the first part is made.
Dimensional verification selected around the part and drawing requirements.
Review material grade, condition and traceability. Material certificates and incoming checks are specified by the purchase requirements. XRF can support alloy screening where appropriate.
Check the first manufactured parts against the drawing and critical characteristics before releasing the approved production route. Agree the FAI format and sample quantity in advance.
Monitor key dimensions at defined manufacturing stages. Checks are selected around process risk, tool wear, stability and the features that cannot be verified after assembly.
Verify agreed characteristics using CMM, optical systems, gauges, micrometers or other suitable equipment. Specify whether sampling or full inspection is required.
FAI, dimensional inspection reports, material certificates, RoHS documentation and CoC are available as agreed. Specify the required standard and traceability level at RFQ stage.
Select packaging around surface protection, cleanliness and transport requirements. Shipping documents and identification are checked against the approved order.
100+ metal & plastic options
Select the exact grade around performance, environment, manufacturing method and cost. Material families alone are not enough to define a part.
Wrought grades and casting alloys are selected for different processes. A356 is evaluated for suitable casting routes; it is not treated as an interchangeable pressure-die-casting alloy.
Review corrosion resistance, machinability, hardness condition and post-processing requirements.
Specify the full grade, supply condition and any heat treatment or hardness requirements.
Select around conductivity, corrosion behavior, strength and machinability. Grade suitability depends on the part.
Exact alloy, stock availability, tool wear and inspection scope require project review.
Machining and molding suitability differ. PTFE and Torlon require process-specific review; not all materials suit conventional thermoplastic injection molding.
Grades shown are options for engineering review, not a claim that every grade is stocked or suitable for every process. Confirm grade, temper, color, additives and documentation before ordering.
Function, appearance and assembly
Finishing changes a part’s surface—and can change the fit. Confirm thickness, masking, roughness and inspection requirements with the drawing.
Finish appearance depends on substrate, alloy, preparation and processing.
We review deburring, polishing, anodizing, plating, coatings, heat treatment and assembly operations together with the manufacturing route. Critical interfaces should be checked in their required final condition.
Explore Surface Finishes →Protective and decorative aluminum oxide finish. Specify color, thickness, masking and sealing.
Wear-focused aluminum finish. Review dimensional growth, alloy response and sealing requirements.
Durable coated surface for suitable substrates. Specify color, texture, thickness and masked interfaces.
Electrochemical finishing for suitable alloys. Review surface targets and dimensional effects.
Surface treatment for suitable stainless steels. Specify the required standard and cleanliness criteria.
Select coating chemistry and thickness around corrosion, wear, conductivity and substrate compatibility.
Define the intended appearance and surface roughness. Cosmetic expectations should be agreed with a sample.
A secondary operation selected for material condition and hardness. Review distortion and any final machining allowance.
From a single interface to a complete component
Metal and plastic components are made to your drawings. Send the geometry, material and intended use so we can assess the right process and inspection plan.
Part families shown for process selection. Dimensions, material and suitability are confirmed for each project.
Explore Our Parts Gallery →Application-driven manufacturing
Match the manufacturing route to the operating environment, critical features and documentation requirements—not just the industry name.
Lightweight brackets, housings, mechanical components and precision assemblies.
Explore Aerospace →Powertrain, testing, vehicle, EV and production-equipment components.
Explore Automotive →Precision housings, fixtures and mechanical components made to the specified drawing.
Explore Medical →Frames, actuator parts, joints, housings and motion-system components.
Explore Automation & Motion Applications →Fixtures, grippers, tooling, machine components and custom assemblies.
Explore Automation →Battery-system, power-electronics and industrial energy-equipment components.
Discuss Energy Components →Industry examples do not imply application approval or sector-specific certification. Regulated or safety-critical requirements must be identified and agreed during quotation.
Decisions supported by manufacturing detail
Down to ±0.005 mm for suitable CNC features, with critical dimensions reviewed before quotation.
Continue from development into pilot builds and repeat orders with an agreed drawing and manufacturing route.
Compare CNC machining, casting, sheet metal and molding through one manufacturing partner.
Review tool access, wall thickness, datums, tolerances and finishing risks before committing to production.
ISO 9001:2015 quality management, agreed inspection planning and project-specific reports.
Metal and plastic grades evaluated around the application, process, availability and documentation needs.
Manufacturing from Dongguan, China, with packaging and delivery planned for overseas engineering and sourcing teams.
A clear path from CAD to delivery
Send 2D drawings and/or 3D CAD files, material grade, quantity, finish and the requirements that control acceptance.
We evaluate geometry, critical tolerances, material, tooling and the manufacturing route. Design risks are discussed before production.
Review pricing, process recommendations, tooling scope and estimated lead time. Confirm inspection, packaging and delivery requirements.
Production starts after drawing revisions, specifications and commercial terms are approved.
Critical dimensions and agreed requirements are checked against the approved inspection plan. Required documentation is prepared.
Parts are protected, packaged and shipped to the agreed destination. Delivery terms and transport arrangements follow the confirmed order.
Send the details that determine the quote
Share your design and application. Our engineering team reviews the material, manufacturing route and critical requirements before confirming pricing and lead time.
STEP | STP | IGES | X_T | STL | DWG | DXF | PDF
Prefer email?
info@tops-precision.com
Answers for engineering and procurement
Precision manufacturing produces components to defined dimensional, geometric, material and surface requirements. The process is selected around the drawing and application, then checked against agreed inspection criteria.
TOPS Precision provides CNC machining, die casting, sheet metal fabrication and plastic injection molding for custom metal and plastic components. Engineering review, tooling, secondary operations, finishing and inspection are planned around each project.
For suitable CNC-machined features, TOPS can support tolerances down to ±0.005 mm. This is not a default tolerance for every dimension or process. Material, geometry, feature size, temperature, finishing and measurement method must be reviewed before the tolerance is confirmed in the quotation.
TOPS supports more than 100 metal and plastic material options across its manufacturing services. Common families include aluminum, stainless steel, steel, copper, brass, titanium and engineering plastics such as ABS, PC, POM, PEEK, Nylon, PP, PMMA and PTFE. Exact grade, stock condition and process suitability are confirmed during review.
Yes. CNC machining and other suitable rapid manufacturing methods can produce prototypes for fit, assembly and functional evaluation. Send your CAD model, critical dimensions and intended test conditions so the prototype material and manufacturing route can be selected appropriately.
Yes. TOPS supports low-volume batches, pilot builds and bridge production. CNC machining, soft tooling where suitable, or other processes are compared using geometry, unit quantity, tooling cost and the expected path to production.
Yes. TOPS supports repeat manufacturing programs. Approved drawing revisions, process settings, inspection requirements and material specifications are used to control subsequent orders. Tooling capacity, lead time and batch size are confirmed for the program.
Inspection is planned around the drawing. TOPS uses CMM, optical measurement, micrometers, gauges and other suitable equipment for dimensional checks. XRF can support alloy-composition screening where appropriate; it does not replace every required material test or certificate.
Yes. Material certificates, dimensional inspection reports, FAI, certificates of conformity (CoC) and RoHS documentation can be provided as agreed for the project. Specify the required standard, report format, sampling plan and traceability level before quotation.
Yes. TOPS manufactures metal components through machining, casting and sheet metal fabrication, and plastic components through machining and injection molding. Material behavior and manufacturing constraints are reviewed separately for each part.
Send the latest 2D drawing and 3D model, material grade, quantity per part, critical tolerances, finish, inspection and documentation requirements, delivery date and shipping destination. STEP, STP, IGES, X_T, STL, DWG, DXF and PDF files can be reviewed.
CNC machining often suits prototypes, lower quantities and critical features without dedicated production tooling. Die casting can suit repeat metal parts when alloy, geometry and quantity justify the tool. Injection molding can suit thermoplastic parts at repeat volumes. Engineers compare total program cost, tolerance, material, tooling and production quantity before recommending a route.
LET’S REVIEW YOUR NEXT COMPONENT
Send the drawing, material and quantity. Start with a practical engineering review of your custom metal or plastic part.
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