Sheet Metal Fabrication Guidelines

Dear Customer,

To avoid any unnecessary disputes, we recommend that you carefully read the following sheet metal fabrication guidelines before placing an order.

1. Supported Drawing Formats for the Sheet Metal Fabrication System

-3D (required): STEP (.step, .stp)

-2D: PDF, DWG, DXF, JPG, PNG

-2D File (DWG,DXF) Requirements for Laser Marking & Silkscreen:

● Please upload the marking/silkscreen drawing that includes the part’s outline, holes (if included), and marked content, based on the actual flat shape after bending--DO NOT upload the unbent unfolded sheet exported from CAD.

● Clearly draw part outline and hole positions (if included).

● Text (if included) must use a double-line font with a 0.2mm line width. See sample image

-Compressed packages (.rar, .zip) can be uploaded directly. Please ensure the package contains the required 3D file (.step, .stp).

-Silkscreen/laser marking drawings should be uploaded under the “Surface Treatment” section.

-Thread/riveting drawings should be uploaded under the “Thread or Riveting File” section.

2. Recommended File Uploads for Optimal Processing

For best results, we recommend uploading a compressed package containing the 3D file (required), 2D file, BOM list, and silkscreen file, ensuring that files for the same design share the same name.

3. Upload Quantity and Size Limits

Each upload can include up to 20 drawings, and each file must be under 100 MB.

4. Guidelines for Assemblies

Due to the special nature of sheet metal assemblies, if parts have an assembly relationship, we strongly recommend uploading them as a complete assembly file.

If you choose to upload them as separate parts, please clearly indicate which parts are related to avoid assembly issues after processing.

Should individual parts be uploaded without clarifying the assembly relationship, we cannot ensure compatibility upon assembly.

5. Minimum Length of Bending Edge and Minimum Distance from Hole to Bending Edge ：

6. Hole Spacing Requirements & Risk Notes  

Min. distance between holes: 1mm. A distance under 1mm will result in a default risk of damage.

7. Bending Outer R Corner Radius

8. Minimum Diameter Specification for Sheet Metal Cutting Holes

The minimum diameter of a cutting hole must be at least half the sheet thickness, and not less than 1 mm.

9. Minimum Width at Center of Bent U-Shaped Structure

(The minimum width position as indicated by the red arrow in the attached figure below)

10. Tolerance Details

11. Welding

Since the welding process may cause issues such as thermal deformation, surface irregularities, and color differences, our standard processing services do not include welding by default.

Should your part require welding, please add a remark during the order submission process.

12. Silkscreen Colors We Support

Kindly note that the actual effect may have slight variations depending on the material's surface treatment (roughness, glossiness) and the lighting conditions of the usage environment.

13. Available Materials, Surface Treatments, and Processes

We offer standardized materials, surface treatments, and machining processes for your selection. For details, please refer to our sheet metal service page: Materials Supported in Sheet Metal Fabrication.

14. Custom Parameters for Sub-Components

We support custom machining parameters for individual parts within an assembly. If you have specific requirements for a sub-component, please specify them in the machining options. The custom part name must match the sub-component name in your design file.

15. Feedback and Contact

If you have any comments or suggestions regarding JLCCNC Sheet Metal services, please contact us: support@jlcpcb.com.

Our team is committed to providing you with the highest level of service.