Measuring Distances in PCB Design with Flux

Check clearances and fits on the board while you design.

Use the automatic and manual measurement tools in Flux to check distances on your PCB.

Overview

Accurate measurements make sure that components fit and that the board meets manufacturing requirements. Flux has automatic and manual measurement tools.

Automatic Measurement

Flux shows automatic measurements in real time as you work. You can check spacing without stopping your design work.

How Automatic Measurements Work

Measurement lines and text appear automatically on the canvas when you select an object and hover over another object:

• By default, measurements display in a straight line between the closest points

• The units are inherited from the selected object

• Hovering near the edge of an element results in edge-to-edge measurements

• Hovering near the center shows center-to-center measurements

Customizing Automatic Measurements

Use these keyboard shortcuts to customize how measurements are displayed:

Manual Measurement

Ask Flux to measure the distance between objects on the board.

You can also do it in the editor.

For more deliberate measurements, use the manual measurement tool to precisely measure the distance between any two points on your PCB.

Using the Manual Measurement Tool

1. Select the empty canvas (click on any area without components)

2. Right-click and select Measure Distance from the context menu

3. Click on the first point you want to measure from

4. Click on the second point to complete the measurement

5. Flux shows the distance. To change the units while you measure, press U

Keyboard Shortcut

• Create a manual measurement: Press M while the canvas is selected

Best Practices for Accurate Measurements

• Use edge snapping: When measuring between components, click precisely on edges for accurate results

• Verify critical clearances: Double-check minimum clearances between high-voltage traces or components

• Measure at multiple points: For irregular shapes, take measurements at several points

• Use X/Y axis measurements: Hold Shift for separate horizontal and vertical measurements when checking alignment

Practical Applications

• Component clearance verification: Ensure components have sufficient spacing for assembly

• Trace width validation: Verify trace widths meet current-carrying requirements

• Manufacturing constraint checks: Confirm your design meets fabrication house specifications

• Thermal management: Measure distances between heat-generating components

Troubleshooting Common Issues

Inconsistent Measurements

• Issue: Measurements seem inconsistent or inaccurate

• Solution: Ensure you're clicking precisely on component edges and check your grid settings

Measurement Tool Not Responding

• Issue: Manual measurement tool doesn't activate when pressing M

• Solution: Make sure you've selected the empty canvas first, not a component

Units Display Problems

• Issue: Measurements display in unexpected units

• Solution: Press U while you measure, or set the Dimension Unit rule. See Managing Units

What's Next

Now that you understand how to use Flux's measurement tools, you might want to explore:

• Design Rule Checks - Learn how to automatically verify design constraints

• PCB Rules Reference - Understand how to set up rules for consistent spacing

• Manufacturing Preparation - Prepare your design for fabrication