How to Generate Gerber Files in ZenitPCB: A Complete Guide for PCB Engineers

After designing dozens of boards using various EDA tools, I’ve found ZenitPCB to be one of the most straightforward options for hobbyists and students who need professional-quality Gerber output without the steep learning curve. This guide walks you through the entire process of generating manufacturing-ready Gerber files in ZenitPCB, from initial setup to final verification.

What Are Gerber Files and Why They Matter

Gerber files serve as the universal language between PCB designers and manufacturers. Think of them as the blueprint that tells fabrication houses exactly how to build your board. Every copper trace, drill hole, solder mask opening, and silkscreen marking gets encoded into these files.

The format originated from Gerber Scientific Instrument Company back in the 1960s when they developed vector photoplotters. Today, the RS-274X (Extended Gerber) format has become the industry standard, embedding all aperture information directly into each file. This eliminates the confusion that plagued the older RS-274D format, which required separate aperture files.

When you send your PCB design to a manufacturer like JLCPCB, PCBWay, or any local fab house, they expect Gerber files. Without them, your beautifully designed circuit stays trapped in your CAD software.

Understanding ZenitPCB Suite Components

Before diving into Gerber generation, it helps to understand what ZenitPCB offers. The suite includes four integrated tools:

Component	Purpose	Key Features
ZenitCapture	Schematic design	Symbol libraries, netlist export, multi-page schematics
ZenitPCB Layout	PCB design and routing	Component placement, manual routing, design rule checking
ZenitParts	Component library editor	Custom footprint creation, library management
ZenitPCB GerberView	Gerber file viewer	Verification before manufacturing

The typical workflow moves from schematic capture to netlist generation, then into the layout editor where you’ll eventually export your Gerber files. Having the built-in GerberView tool means you can verify your output without installing third-party software.

Prerequisites Before Generating Gerber Files in ZenitPCB

Getting manufacturing-ready files requires more than just clicking export. Here’s what you need to complete first:

Design Rule Check Completion

Run the online DRC (Design Rule Check) before exporting anything. ZenitPCB’s built-in checker will flag violations like clearance issues, unconnected nets, and silkscreen overlapping pads. Manufacturers will reject files with obvious DRC errors, so fix these first.

Layer Stack Verification

Confirm your layer configuration matches your manufacturing intent. ZenitPCB supports single-sided and double-sided designs with up to 800 pins in the free version. Make sure each layer contains the correct data before export.

Board Outline Definition

Your board outline must be clearly defined. Without it, manufacturers cannot determine the physical dimensions or how to panelize your design. Check that your outline forms a closed shape with no gaps.

Step-by-Step Guide to Generate Gerber Files in ZenitPCB

The actual export process in ZenitPCB follows a logical sequence. Here’s how to get it done:

Step 1: Open Your PCB Project

Launch ZenitPCB Layout and open your completed PCB design file. Make sure all components are properly placed and all routing is finished. Any floating traces or unconnected pins will appear in your Gerber output.

Step 2: Access the Gerber Output Menu

Navigate to the File menu and locate the Gerber output option. ZenitPCB uses the Gerber 274X format by default, which is exactly what modern manufacturers expect. This embedded aperture format keeps all layer information self-contained.

Step 3: Configure Layer Selection

The layer selection dialog lets you choose which layers to export. For a standard two-layer board, you’ll typically need:

Layer Type	File Extension	Description
Top Copper	.GTL	Top signal layer with all traces and pads
Bottom Copper	.GBL	Bottom signal layer
Top Solder Mask	.GTS	Defines areas where solder mask is removed
Bottom Solder Mask	.GBS	Bottom side solder mask definition
Top Silkscreen	.GTO	Component outlines and reference designators
Bottom Silkscreen	.GBO	Bottom side markings
Board Outline	.GKO or .GM1	Physical board boundary

Step 4: Set Units and Precision

ZenitPCB allows configuration in millimeters (minimum 0.01mm) or mils (minimum 0.001 inches). Match your unit setting to whatever you used during design. Most manufacturers accept either, but consistency prevents conversion errors.

The coordinate precision typically uses 2:4 or 3:3 format (integer:decimal digits). Higher precision means larger files but more accurate representation of your design geometry.

Step 5: Generate the Gerber Files

Click the generate button to create your Gerber files. ZenitPCB will process each selected layer and output individual files to your specified directory. The process usually completes within seconds for typical hobby-sized boards.

Step 6: Generate NC Drill Files

Gerber files don’t include drill information—you need separate NC Drill (Excellon) files. Access the NCDrill output option, typically in the same menu area. Configure the drill file to include:

• Plated through-holes (PTH)
• Non-plated through-holes (NPTH)
• Via holes
• Mounting holes
• Slot information (if applicable)

The drill file uses Excellon format and typically has a .DRL or .TXT extension.

Gerber File Types Explained for ZenitPCB Users

Understanding what each file contains helps you verify your output. Here’s a breakdown:

Copper Layers

These files define all conductive patterns including traces, pads, and copper pours. The top copper layer (.GTL) shows everything visible from the component side, while bottom copper (.GBL) shows the solder side.

Solder Mask Layers

Solder mask files use negative logic—filled areas indicate where the mask should be removed, exposing copper. This exposes pads for soldering while protecting traces from oxidation and solder bridges.

Silkscreen Layers

Also called legend layers, these contain component outlines, reference designators (R1, C2, U3), and any text you’ve added. Good silkscreen design helps during assembly and troubleshooting.

Paste Layers

If you’re doing SMT assembly with solder paste stencils, paste layers define the stencil openings. These typically match your solder mask openings but may be slightly smaller to control paste volume.

Mechanical and Outline Layers

The board outline defines your PCB shape. Any cutouts, v-scores, or special mechanical features should also appear here. Some designers include a separate keepout layer.

Best Practices for ZenitPCB Gerber Generation

After working with numerous manufacturers, I’ve learned these practices prevent costly mistakes:

Always Verify Before Sending

Use ZenitPCB GerberView or an external viewer like Gerbv (free and open-source) to inspect every layer. Stack all layers together and check for alignment issues. Verify that drill holes align with pads.

Include a README File

Create a simple text file listing all included files with descriptions. Mention any special requirements like controlled impedance, specific materials, or surface finish. This helps CAM engineers understand your intent.

Package Files Correctly

Combine all Gerber and drill files into a single ZIP archive. Most manufacturers have online Gerber viewers that automatically extract and process ZIP files. Keep file names clear and descriptive.

Check Manufacturer Requirements

Different fabricators have different preferences. Some want specific file extensions, others prefer certain coordinate formats. JLCPCB, for instance, publishes detailed requirements for optimal results.

Common Gerber Generation Issues in ZenitPCB

Even experienced designers encounter these problems:

Drill File Offset

If your Gerber viewer shows drill holes shifted from pad centers, the coordinate format doesn’t match between Gerber and drill files. Regenerate both using the same unit and precision settings.

Missing Board Outline

Manufacturers can’t cut your board without an outline layer. If your outline doesn’t export properly, check that you’ve drawn it on the correct mechanical layer and that it forms a completely closed path.

Silkscreen Over Pads

Text or component outlines overlapping exposed copper will be rejected or removed by manufacturers. Check that your silkscreen clears all pad openings by an adequate margin.

Negative Layer Issues

Inner plane layers sometimes export in negative format where filled areas indicate copper removal. Verify your manufacturer can handle negative layers, or export in positive format.

ZenitPCB Gerber Output Configuration Table

Setting	Recommended Value	Notes
Format	RS-274X (Gerber X2)	Self-contained aperture information
Units	Match design units	Millimeters or inches
Precision	3:3 for mm, 2:4 for inches	Higher precision for fine-pitch designs
Leading Zeros	Suppress	Standard industry practice
Coordinate System	Absolute	Most common format
Mirror	None (unless specifically needed)	Bottom layer auto-handled

Useful Resources for ZenitPCB Users

Here are essential links for anyone working with ZenitPCB and Gerber files:

Resource	URL	Description
ZenitPCB Official Site	www.zenitpcb.com	Download software and documentation
ZenitPCB Download Page	www.zenitpcb.com/DownLoad.html	Latest version and license files
Gerbv Viewer	gerbv.github.io	Free open-source Gerber viewer
FlatCAM	flatcam.org	Gerber to G-code converter for CNC
ViewMate	www.pentalogix.com/viewmate.php	Advanced Gerber viewer
Ucamco Reference Viewer	www.ucamco.com	Official Gerber format developer
JLCPCB Order Guide	jlcpcb.com/help	Manufacturing requirements
PCBWay Guidelines	www.pcbway.com/helpcenter	Alternative manufacturer specs

Comparing ZenitPCB Gerber Output to Other Software

ZenitPCB offers streamlined Gerber export compared to more complex tools:

Feature	ZenitPCB	KiCad	Altium
Gerber Format	RS-274X	RS-274X/X2	RS-274X/X2
Built-in Viewer	Yes	No (requires plugin)	Yes
Export Complexity	Low	Medium	High
Batch Export	Limited	Yes	Yes
Price	Free	Free	Commercial
Learning Curve	Easy	Moderate	Steep

Frequently Asked Questions

What Gerber format does ZenitPCB support?

ZenitPCB generates Gerber RS-274X files, which is the extended format with embedded aperture definitions. This format is universally accepted by PCB manufacturers worldwide and eliminates the need for separate aperture files that the older RS-274D format required.

Can I generate multi-layer Gerber files in ZenitPCB?

ZenitPCB primarily supports single and double-sided PCB designs. For complex multi-layer boards with four or more layers, you’d need to consider more advanced tools like KiCad or Altium. However, for typical hobby and educational projects, two layers cover most requirements.

How do I verify my Gerber files before sending to manufacturers?

Use the included ZenitPCB GerberView tool to inspect each layer individually and as a stack. Alternatively, free viewers like Gerbv or online tools from manufacturers like JLCPCB provide additional verification. Check alignment, drill locations, and layer registration carefully.

What drill file format does ZenitPCB generate?

ZenitPCB outputs NC Drill files in Excellon format, which is the standard for CNC drilling machines. The file includes tool definitions, hole sizes, and coordinate positions. Make sure to include this file with your Gerber package since manufacturers need both.

Why are my drill holes offset from the pads in the Gerber viewer?

This typically happens when the coordinate precision or units differ between your Gerber and drill files. Regenerate both file types using identical settings. If the problem persists, try switching between leading zero suppression options.

Advanced Tips for Professional Gerber Output

Beyond the basic export process, these techniques will elevate your manufacturing results:

Optimizing Copper Pour Generation

Copper pours (ground planes or power planes) can significantly affect your Gerber file size and manufacturing quality. Before exporting, ensure your pours are properly connected to the appropriate nets. ZenitPCB’s copper plane feature creates solid fills, but verify that thermal relief connections on through-hole pads allow proper soldering.

When reviewing the Gerber output, copper pours should appear as uniform filled regions without gaps or artifacts. If you notice strange patterns, regenerate the pour in your design before re-exporting.

Managing Silkscreen Clarity

A well-designed silkscreen layer makes assembly and debugging much easier. In ZenitPCB, take time to position reference designators so they remain readable after manufacturing. Keep text at least 0.15mm (6 mils) away from solder mask openings to prevent the manufacturer from trimming your labels.

Recommended silkscreen text specifications:

Parameter	Minimum Value	Preferred Value
Text Height	0.8mm	1.0mm
Line Width	0.15mm	0.2mm
Spacing from Pads	0.15mm	0.25mm
Font	Sans-serif	Arial or similar

Handling Special Features

If your design includes slots, oval holes, or cutouts, verify these appear correctly in your drill and outline files. ZenitPCB supports slot output alongside standard drill files. Check that your manufacturer can process slot data—most modern fabs handle it without issues, but it’s worth confirming.

For non-rectangular board shapes, your outline layer becomes critical. Complex outlines with internal cutouts require careful verification. Use the Gerber viewer to trace the entire board boundary and confirm it forms a continuous, closed path.

Understanding Manufacturer Requirements for ZenitPCB Files

Different fabrication houses have varying requirements. Here’s what major manufacturers typically expect:

JLCPCB Requirements

JLCPCB accepts Gerber RS-274X files in ZIP format. They provide an online Gerber viewer that previews your board before ordering. Their system automatically detects layer functions based on file extensions, so using standard extensions (.GTL, .GBL, .GTS, etc.) ensures smooth processing.

PCBWay Specifications

PCBWay similarly accepts RS-274X format and provides detailed feedback if issues are detected. They recommend including a clear board outline layer and specifying any special requirements (controlled impedance, gold fingers, etc.) in your order notes.

AllPCB Guidelines

For AllPCB and similar services, the standard Gerber package works well. They appreciate clearly labeled files and a complete layer stack without missing elements.

Troubleshooting Gerber Generation Problems in ZenitPCB

When things go wrong, systematic troubleshooting saves time:

Problem: Empty or Incomplete Layer Files

If a generated Gerber file appears empty in the viewer, the layer likely has no data assigned to it in your design. Return to ZenitPCB Layout and verify that the layer actually contains design elements. Sometimes designers accidentally place elements on wrong layers.

Problem: Aperture Warnings

Modern RS-274X format handles apertures automatically, but if you encounter warnings about undefined apertures, check that your design doesn’t use custom shapes that ZenitPCB cannot represent. Standard pads and traces should export without issues.

Problem: File Size Anomalies

Extremely large Gerber files (megabytes for simple boards) suggest a problem with copper pour generation or complex geometry. Simplify decorative elements or graphics that might be creating excessive data.

Unusually small files might indicate missing data. Compare file sizes between layers—copper layers should generally be larger than silkscreen layers.

Problem: Import Failures at Manufacturer

If a manufacturer’s system rejects your files, ask for specific error messages. Common issues include:

• Mixed units between files
• Corrupt or truncated files
• Missing drill file
• Unsupported file extensions

Regenerate the affected files and verify them in an independent viewer before resubmitting.

ZenitPCB Workflow Integration

For the smoothest experience, integrate Gerber generation into your overall design workflow:

Pre-Export Checklist

Create a checklist you follow before every export:

1. Run DRC and fix all errors
2. Verify all nets are connected
3. Check board outline is closed
4. Review silkscreen placement
5. Confirm copper pours are generated
6. Save your design file
7. Note any special manufacturing requirements

Post-Export Verification

After generating files:

1. Open each file in GerberView
2. Stack all layers and check alignment
3. Verify drill holes center on pads
4. Check board outline matches intended dimensions
5. Confirm silkscreen doesn’t overlap pads
6. Review solder mask openings

File Management

Develop consistent naming and organization habits:

• Use descriptive folder names including project name and revision
• Include a dated README with any special notes
• Keep the original ZenitPCB project file alongside Gerbers
• Archive successful Gerber packages for reference

When to Consider Alternatives to ZenitPCB

ZenitPCB excels for simpler designs, but recognize its limitations:

The 800-pin limit restricts complex designs. If your projects routinely exceed this, consider transitioning to KiCad (free and open-source) or commercial options like Altium Designer.

Multi-layer boards beyond two layers require different tools. ZenitPCB focuses on single and double-sided designs, which covers most hobbyist needs but may not suit advanced applications.

Automated routing features are limited in ZenitPCB. For dense boards requiring autorouting, other tools provide more sophisticated algorithms.

Despite these limitations, ZenitPCB remains excellent for learning PCB design fundamentals and producing quality boards for straightforward projects.

Final Thoughts on ZenitPCB Gerber Generation

Generating proper Gerber files marks the transition from design to physical reality. ZenitPCB makes this process accessible for hobbyists and students while maintaining the professional standards manufacturers expect. Take the time to verify your output using the built-in GerberView or external tools, and always include all necessary files in a properly organized package.

The key to success lies in methodical preparation: complete your DRC, verify your layer stack, generate all required files, and inspect everything before uploading to your chosen manufacturer. With ZenitPCB’s straightforward interface and RS-274X output, you’re well-equipped to turn your designs into real circuit boards.

Whether you’re building your first LED blinker or prototyping a more ambitious project, the Gerber generation process remains consistent. Master it once, and you’ll confidently produce manufacturing-ready files for every future design.