Overview
XCM CNC provides custom zinc turning and milling for Zamak 3, Zamak 5, and Zamak 8 die-cast parts that need fit-surface finish machining, hole-position correction, and datum rework after casting.
With ISO 9001 and IATF 16949 aligned systems and machines from brands such as DMG and Mazak, we review datum choice, die-cast allowance, and the pre-finish machining zone before sampling starts. MOQ starts from 1 piece, sample lead time is usually 3-7 days, and repeat production often runs in the 10-15 day range once the sample route is approved.
Key Capabilities
Machining Parameters
- Materials: Zamak 3, Zamak 5, Zamak 8 by drawing review
- Tolerance: +/-0.003 mm (+/-0.00012 inch), IT5 or IT6 accuracy, +/-0.01 mm shaft and bore fits, with h6 and H7 available
- Surface Finish: Ra 3.2 um milled, Ra 1.6 um precision, Ra 0.8 um turned or bored
- GD&T: Coaxiality 0.012 mm, runout 0.01 mm, cylindricity 0.011 mm
- Max Size: Milling 3000 x 1600 x 1400 mm, turning diameter 1250 x 2000 mm
- Surface Treatment: Plating, powder coating, chromate finish, painting, or cosmetic prep by drawing review
- Thread: M1.4-M220, NPT, BSP, G, PT
- Inspection: CMM report, FAI report, and material certificate by order requirement
DFM Review for OEM Zinc Drawings
Zinc OEM drawing review can lock +/-0.003 mm critical features and 0.015 mm position tolerance before sample approval. When the program changes between Zamak 3, 5, or 8, includes thin-wall die-cast housings, or needs 0.01 mm hole position control, we confirm stock allowance, fixture datums, and the inspection scope during the sample review.
Sample Approval for Thin-Wall Zinc Parts
Zinc sample approval can reserve Ra 1.6 um mating faces and Ra 0.8 um turned or bored functional surfaces on functional areas. When the geometry approaches 0.5 mm walls, H7 fits, or multi-face setups, the first article also checks heat buildup, springback, and the deburring range.
Revision Control for Critical Fits
Zinc revision changes should trigger a recheck of 0.012 mm coaxiality and 0.01 mm runout on shaft-bore and flange interfaces. When a revision affects deep cavities, long slots, or fit-critical faces, the toolpath, stock allowance, and reinspection sequence are reviewed again around 0.02 mm flatness and +/-0.003 mm precision features.
Reinspection After Surface Preparation
Zinc protected parts can keep Ra 3.2 um standard milled faces while reserving key areas for plating or cosmetic surface preparation. For lock-hardware fits, electronic shielding housings, and precision interfaces after die casting, the sample route can recheck 0.015 mm hole position and 0.012 mm coaxiality with CMM and supporting order documents.
Specifications
| Product Name | OEM Zinc CNC Turned and Milled Parts Supplier |
|---|---|
| Manufacturer | XCM CNC |
| Factory Location | Shenzhen, Guangdong, China |
| Quality System | ISO 9001, ISO 13485, IATF 16949, GJB9001C |
| Machining Process | CNC turning, CNC milling |
| Material | Zinc |
| Material Grade | Zamak 3, Zamak 5, Zamak 8 by drawing review |
| Tolerance | +/-0.03 mm standard CNC machining tolerance |
| Precision Tolerance | +/-0.003 mm for selected critical features by drawing review |
| Surface Roughness | Ra 3.2 um milled, Ra 1.6 um precision, Ra 0.8 um turned or bored |
| Surface Treatment | Plating, powder coating, chromate finish, painting, or cosmetic prep by drawing review |
| Max Part Size | Milling 3000 x 1600 x 1400 mm / Turning diameter 1250 x 2000 mm |
| Inspection | CMM, roundness tester, height gauge, roughness tester, thread gauges |
| Application | Die-cast trim parts, lock-hardware fits, and EMI cover finish machining |
| Typical Application | Drawing-based zinc die-cast secondary machining |
| Key Features | Die-cast follow-up machining, fit-surface correction, DFM review, and sample approval |
| Critical QC Requirements | Casting datum review, fit-surface inspection, deformation control, finish allowance check, and post-process reinspection |
| Batch Range | 1 piece to low-volume repeat production |
| MOQ | 1 piece |
| Typical Lead Time | Samples 3-7 days, repeat production 10-15 days by drawing review |
| Drawing Formats | STEP, IGS, DWG, PDF, X_T |
| Secondary Process | Deburring, tapping, cosmetic-prep machining, plating prep, and dimensional reinspection |
| Material Certificate | Material certificate by order requirements |
| Material Feature | Die-cast follow-up machining, fit-surface correction, and pre-finish machining review |
| Assembly Features | Die-cast mating faces, threaded inserts, locking features, and EMI cover interfaces by drawing review |
Applications
Automotive Zinc Die-Cast Fit-Surface Machining
Typical Parts: Door latch housing, fuel cap internal bracket, seat-adjustment knob base
CNC finish machining after die casting can correct hole position and mounting-face flatness on automotive zinc parts. During drawing review, we confirm die-cast allowance and assembly datums first, then machine fit holes to H7 class and control position tolerance to 0.015 mm where required, with CMM and FAI reporting available by order.
Lock Cores and Handle Mating Surfaces
Typical Parts: Lock core housing, handle base, knob seat
Zinc lock and handle parts often need secondary machining on critical fit surfaces before plating or coating. Lock bores can be turned to Ra 0.8 um, handle datum faces can be precision milled to Ra 1.6 um, and the finish allowance plus appearance standard are fixed during the sample stage.
EMI Shield Housings and Connector Shells
Typical Parts: 5G base-station filter shield can, fiber-module retention shell, non-structural EMI shielding frame
Finish machining on thin-wall shielding cavities and connector shells must control fixture distortion and wall-thickness stability. Structures near 0.5 mm thickness can use staged fixturing and low cutting parameters, while grounding faces and clip-hole positions follow the drawing before plating or appearance work starts.
Toy Model Decorative Pieces and Small Accessories
Typical Parts: Model decorative part, clip accessory, small housing
Appearance correction and size consistency on small zinc parts directly affect final assembly quality. Small housings and clip parts can keep visible faces at Ra 1.6 um, while burr direction and tool marks are confirmed at the sample stage and later batches follow the same first-article standard on key dimensions.
Why Choose Us
Qualified Systems and Equipment Coverage
XCM CNC runs zinc die-cast secondary machining under ISO 9001, ISO 13485, IATF 16949, and GJB9001C aligned quality systems, while using equipment from brands such as DMG, Mazak, Matsuura, and Brother for fit-surface correction and multi-face machining. For Zamak series projects, we review datum choice, pre-finish allowance, and reinspection priorities during drawing review.
Broad Size Range for Zinc Finish Machining
We support zinc finish machining from small connector-scale parts to larger housings, covers, and medium-size structural parts. Three-axis travel reaches 3000 x 1600 x 1400 mm and turning capacity reaches diameter 1250 x 2000 mm, while the final route still follows the die-cast datum, the pre-finish allowance, and the fixture method.
Tiered Equipment Strategy for Cost and Quality
XCM CNC uses CNC equipment from mainland China, Taiwan, Japan, and Europe or the US in a tiered production mix. Lower-tolerance operations can run on domestic or Taiwan machines, while higher-precision critical work moves to imported machines such as DMG and Mazak. That helps reduce cost without placing simple operations onto high-hour machines.
Front-Loaded Drawing Review and Process Planning
Zinc die-cast projects are stronger when 2D and 3D drawings, datum choice, fit faces, and pre-finish allowance are reviewed before the sample route instead of after the first build. Zamak 3, 5, and 8 differences can also affect machining parameters and the later finish route, and NDA support is available before review starts.
Sample Approval That Transitions to Batch Work
Zinc samples usually need the casting offset, fit-surface correction, and thin-wall fixturing method confirmed before batch scheduling begins. When the design changes, we review holes, appearance faces, and the pre-finish state first, then update the reinspection list before repeat production starts.
FAQ
Why do zinc die-cast parts still need CNC finish machining?
Zinc die-cast parts often need CNC correction on critical holes, fit faces, and assembly datums because die casting alone usually cannot hold the required assembly tolerance. The final machining scope still depends on part structure, tolerance level, and the later surface-treatment route.
How do you choose Zamak 3 or Zamak 5 for a zinc CNC part?
Zamak 3 is often used on standard die-cast parts with balanced strength and flow, while Zamak 5 offers stronger creep resistance and can be better suited when higher strength or plating quality matters. The final grade should still follow the service condition and the planned finishing route.
What surface treatments are common for machined zinc alloy parts?
Common zinc finishing routes include nickel plating, chrome plating, chromate finish, powder coating, and painting. The final process and coating target should follow the part function and the required appearance standard.
When should zinc alloy be chosen instead of aluminum for machined parts?
Zinc is often a better choice when the project is centered on die-cast follow-up machining, complex appearance parts, or medium-size batches that need fit-surface correction after casting. The main condition is that the part strength, weight, and service temperature stay within zinc alloy limits.
What drawing files and casting details do you need for custom zinc finish-machined parts?
Quotation and DFM review usually need 2D and 3D drawings such as STEP, IGES, STP, DWG, or a dimensioned PDF, together with the grade, tolerance requirements, quantity, and any note about the pre-cast condition. If the part includes key fit faces, appearance faces, or later finishing, those sample-review priorities should be marked from the start, and NDA support is available.
How do you handle zinc die-cast revision changes after sample approval?
If a zinc part changes after sample approval, we first review the datum choice, the correction allowance, and the critical-face condition. Whether a new sample or an updated reinspection plan is needed depends on what changed in the revision.
Request a CNC Machining Quote from XCM CNC
Send us your drawings. Our team will review the file and reply with a machining quote. MOQ: 1 piece, with competitive low-cost pricing.
Email: [email protected] | WhatsApp: +8618638951317
