Device Settings: Dimensions / Units

The Dimensions / Units tab of Device Settings contains settings related to units and measurement and is available regardless of device type.

The image below shows the Dimensions / Units tab for a DSP device. Click any option in the image below to jump directly to the relevant section for that option, or scroll down for a full list of options and descriptions.

Working Size¶

The maximum X (Width) and Y (Height) travel for your laser. This sets the size of the work area in LightBurn, but does not affect the laser itself.

CNC Machine¶

Enable this setting if working with a machine with a rear-right origin and negative workspace coordinates. CNC machine users may also want to try MillMage.

Machine Coordinates¶

Enable this setting when working with a CNC machine that uses G54 offsets.

LightBurn works best with the G54 Workpiece Coordinate Offset set to 0,0,0. You can set this in the console by entering G10 L2 P1 X0 Y0 and pressing enter, while connected to your machine. If you do need to use the G54 offset, enabling Machine Coordinates will fix some problems, but not all. In particular, User Origin workflows and Continuous Jogging may not work correctly with a G54 offset.

Origin¶

The location of your laser's Origin, or home. If this is set incorrectly, the orientation of your laser's output will be mirrored or inverted.

For help with troubleshooting your laser's Origin, please see Troubleshooting: Wrong Orientation.

Laser Offset¶

If your laser has a red dot pointer for Framing and positioning, this setting allows you to compensate for misalignment between the pointer and the actual cutting location. Enable this setting to shift the laser's output relative to the red dot location.

See Laser Offset Setup for instructions on calculating the offset.

Enable U Axis¶

Enable this setting to apply per-layer U Axis offsets. This is not supported by all controllers.

Device Units¶

Use this section to tell LightBurn whether your device expects to receive metric or imperial units. Most machines will use metric. Not all device types will have this section.

Control Units¶

This section sets the Control Units for your currently active device, which are the units used for speed and distance when controlling your device.

If you prefer to design in inches but use metric units for speed, choose Inches / mm/sec for CO₂ and Galvo lasers or Inches / mm/min for diode lasers.

Link Control and Design Units¶

By default, Control Units and Design Units are linked, so switching between millimeters and inches for either one will switch both. To unlink the two types of units, turn off the Link Control and Design Units toggle. To relink them, enable the toggle.

Z Control¶

This section contains settings for your laser's Z Axis, which controls the distance between the laser and the workpiece. The options available will vary depending on what laser you're using.

Enable Z Axis¶

Enable this to allow LightBurn to control the Z Axis of your machine.

Reverse Z Direction¶

If your machine's Z Axis moves in the opposite direction of what you expect, toggle this switch to flip the direction for Z moves.

Relative Z Moves Only¶

This setting treats the machine's height at the start of the job as 0, and uses that height as the starting point for all Z moves. Material height is ignored when Relative Z Moves are enabled.

This is the simplest way to work, as you set your focus according to the manufacturer's directions and LightBurn will treat that height as the correct height to start from.

Optimize Z Moves¶

By default, LightBurn always retracts the Z back to the starting height after completing a shape with a Z Offset. This is done to prevent the laser head from crashing into the workpiece.

With Optimize Z Moves enabled, LightBurn will only issue Z moves when the Z height actually changes. If you know your material is flat and that none of the Z moves will result in the laser moving low enough to run into anything on your work table, this can save a lot of time.

OMTech Polar¶

Enable this if using an OMTech Polar device.

Troubleshooting¶

• If you aren't seeing a setting you expected to see, check which tab you're in and make sure it's applicable to your laser.

Related Topics¶

• Settings/Preferences
• Machine Settings
• Devices