Line Mode

Line Mode tells your laser to trace a path around the contours of vector graphics.

If you command the laser to move quickly, or with low Power, it will likely just etch the surface (sometimes called scoring). If you move slowly and with high power, especially with a CO₂ laser, the laser will cut deeper, or even completely through the material. The only difference between surface marking and cutting with Line Mode is the Power and Speed you set.

Line Mode Settings

There are several specialized options available in the Cut Settings Editor for layers set to Line Mode, split into two tabs, Common and Advanced.

Note

See Main / Shared Settings for information on applying essential settings like Speed and Power.

See Additional Options for information on specialized settings not covered on this page.

Click any option in the images below to jump directly to the relevant section for that option, or scroll down for a list of options and descriptions.

Many of the settings presented in the images below are available for users with DSP lasers only, but most are shared between all types of lasers.

Left: Common Line Mode settings tab

Right: Advanced Line Mode settings tab

Common Settings

Number of Passes

How many times the laser will repeat the shapes on this layer. Sometimes, when cutting thick material, trying to engrave very deep, or using a lower power laser, more than one pass may be necessary.

Z Offset

If you have Z movement enabled, and your controller supports it, you can use the Z offset setting to move the laser head closer to the material (inward) or farther away from it (outward). Positive values move the Z Axis inward, and negative values move it outward.

Focusing deeper into the material can sometimes help to cut thicker material, and lifting the laser away from the material can produce a thicker line.

Warning for Z Moves

Z moves have the potential to physically damage your laser by crashing the head into the material.

If your system uses auto-focus, you may not be able to push the focus point lower, because most systems treat the auto-focus height as the lowest possible height (Z limit) to avoid crashing the laser head.

Z Step per Pass

When doing more than a single pass over a shape, the Z step per pass setting allows you to tell LightBurn to raise or lower the laser with each pass by the same amount.

By allowing you to shift the focus point deeper with each pass, this is often useful for cutting thick materials or achieving deep engravings.

Kerf Offset

Closed Shapes Only

This feature only works with shapes that are closed. A shape is closed when it is a complete, continuous loop whose start and end points are the same. When a shape's start and end points are different, it is open.

See Open vs. Closed Shapes for more information.

Kerf refers to the thickness or width of a cut made by a cutting tool. The kerf of a laser is much narrower than that of a saw blade, but the extra material removed can interfere with close-fitting parts such as tabbed boxes or inlays.

Kerf Offset compensates for the extra material removed by offsetting the path of the laser to the outside of closed shapes (for positive values) or the inside (for negative values). This doesn't modify the underlying shape, so you can use your design on lasers with different kerfs by adjusting the Kerf Offset value.

The image below shows how Kerf Offset (dashed lines) relates to the original shape (solid lines).

Perforation Mode

Enable Perforation Mode to specify a distance to Cut, followed by a distance to Skip.

As the laser traces the contours of shapes assigned to this layer, it will turn on over the specified Cut distance, and off over the specified Skip distance.

Perforation Mode is useful if you're trying to cut fold lines in card stock, stitch holes in leather, or make dashed lines.

Use Perforation Mode to reduce effective power output

This can also help when using delicate materials with a powerful laser. With very low cut and skip values, the beam is rapidly switched on and off, reducing the effective power output. Try starting with cut and skip values of 0.1 mm each, and adjust the ratio between cut and skip to tune it further.

Tabs / Bridges

Tabs are small sections of cuts that the laser is commanded to skip, used to prevent objects that you are cutting from immediately falling out of the base material. When sized appropriately, the tabs can be broken with minimal force and the objects removed from the material after the job is finished cutting.

See Add Tabs for information on creating and adjusting Tabs / Bridges settings.

Advanced Settings

Under the Advanced tab you'll find several less frequently-used options. Many of the options presented here are available only for particular types of lasers.

Note

The Advanced tab is not available if you're using a Galvo laser. See Galvo-Specific Cut Settings for information on advanced settings for Galvo lasers.

Start / End Pause Time

Use these options to add a delay, in milliseconds, at the beginning of a cut, the end, or both.

If you also enable the Cut Through option, the beam will be turned on during this pause, which can be used to prime the cut and help pierce through thick material. The Power % value sets the power of the laser during this pause.

Without the Cut Through toggle enabled, it can add a delay to let the gantry settle down after a rapid move, or allow time for an air assist solenoid to engage.

Note

This setting is not available for lasers with TopWisdom controllers. Dwelling without Cut Through enabled is not available for lasers with Trocen controllers.

Overcut

Enable Overcut to tell your laser to extend a cut by a specified amount past the end of closed shapes, on the final Pass.

Override PWM Frequency

If you have an RF Excited tube, this setting allows you to control the PWM frequency of the pulses sent to the laser, and can change the edge finish on certain materials.

Note

This setting is only available for lasers with Ruida controllers.

Enable PPI

The PPI setting (Pulses Per Inch) lets you tell the laser to send an exact number of pulses per inch of travel, instead of varying the beam power directly. This is useful for delicate materials like paper, and is similar to using Perforation Mode, but is handled by the hardware itself.

Note

This setting is only available for lasers with Trocen controllers.

Lead-In / Lead-Out

Lead-In and Lead-Out are optional lines or curves added to the start or end of a cut. You can toggle each on or off individually, and specify their Angle, Length, and Style.

When cutting thick material, particularly if using Cut Through delays, or cutting metal, there is often a mark left at the start of the cut that is slightly thicker than the rest, and can leave an indent on an otherwise smooth edge. With this setting, you can add a small line to the start or end of a cut, so that mark happens off the cut line itself.

The Angle value controls the placement of the lead line — a positive number tells LightBurn to put the lead line outside the shape, and a negative number means to put it inside. You can choose to make the lead a straight Line, or a short Arc.

The shape above on the left is using an Arc set to +45 degrees, so it starts outside the shape. The one on the right is a Line set to -20 degrees, so it appears inside the shape.

Set Lead-In/Out Start Points

1. Click on the design element. Elements created with the Shape tool may not display any nodes or points along the selected elements, while path-based objects will display their nodes.

   

   Rectangle Created With Create Shapes Tool | No Visible Nodes

2. With the desired shape selected, click on the Edit Nodes tool in the Creation toolbar and either:

   Objects Created With Draw Shapes Tool

   

   No Visible Nodes

   Convert to Path

   Objects created with the Draw Shapes tool may need to be converted to a Path object in order to access the object nodes.

   

   Visible and Editable Nodes

   a. With the object selected, click on the Edit menu and select Convert to Path, or on your keyboard press Ctrl/Cmd + Shift + C.

   Objects Created With Draw Lines Tool or Path-based Objects

   

   Visible and Editable Nodes

   b. Continue to the next step.

3. Add an new node along the edge/face of the desired Lead-In/Out location. Curved shapes may be able to use existing nodes. Nodes that anchor acute angles (less than 90°) may not be compatible with internal Lead-In/Out locations.

   

4. Select the Set Start Point tool and click on the new node to set that node as the shape's Lead-In/Out location.

   

Activate Lead-In/Out at Start Points

Shapes with active Lead-In and Lead-Out points will share the same angle, length, and style settings on that layer. Assign shapes to different layers to use different Lead-In/Out settings in the same project.

1. Open the Cut Settings Editor to activate the Lead-In/Out for that shape by double-clicking the assigned layer.

   

2. In the Advanced Tab, activate the Lead-In and/or Lead-Out toggle and set your

   1. Desired angle, with positive angles for Lead-In/Outs external to that object, or negative angles for internal Lead-In/Outs. Lead-In/Outs assigned to lines will use positive values for Lead-In/Outs above the line and negative values for Lead-In/Outs below the line.
   2. Desired Lead-In/Out length
   3. Choose between Line or Arc-shaped Lead-In/Outs.

3. Click on OK to save the Lead-In/Out settings for all shapes assigned to that layer. Use different layers for different Lead-In/Outs settings within the same project.

   

4. Assign additional Lead-In/Out points to any remaining shapes as desired and repeat the process for each additional layer as needed.

   

5. Click on the Preview Icon in the main toolbar to view the updated Lead-In/Outs for each assigned shape and start the job when ready through the Laser window.

   

Reducing Travel Moves

Set Cut Order Priority

Reduce the travel moves your laser cutter makes by manually setting the Cut Order Priority of each shape to align the Set Start Point assigned to one shape to the Start Point location on another shape.

1. Click on the Optimization Settings button in the Laser window to open the Cut Optimization Settings window.

   

2. Click on Order by Priority to use the Cut Order Priority assigned to each shape. Click on the Remove button as needed to remove existing entries or reorder by clicking and dragging on each Order by item.

   

   

3. Click OK to save the new job priority settings.

   

4. Open the Shape Properties window to assign the Cut Order Priority to each shape by selecting the Shape Properties tab found in the right-hand side of the main window by default and assign a priority to each shape starting from 0 (zero), onwards..

   

   Tip

   The layout of LightBurn is highly customizable. For more information on enabling and disabling windows and toolbars, or rearranging the default layout, see Customizing the LightBurn Window.

5. Open the Preview window by selecting the Preview window button in the main toolbar to view the updated cutting path and start the job once ready.

   

Dot Mode

When enabled, the laser will pause and pulse at regular intervals along the path, instead of cutting continuously. The Time value specifies the pause delay in milliseconds, and the Spacing parameter sets how far apart the pulses are.

This can be an effective way to do stitching holes, or cut very thin or delicate materials, but the constant pausing can shake the machine — using Perforation Mode is often preferable for this reason.

Note

This setting is only available for lasers with Ruida controllers.

U Offset

Enter a distance here to set a per-layer U Axis offset. To use this setting, your laser must support U Axis control, and you must enable the U Axis in Device Settings.

Note

This setting is only available for lasers with Ruida controllers.

Additional Options

The settings presented in the Cut Settings Editor depend on the selected Layer Mode and the type of laser you're working with. Select an option below to learn more about different groups of settings.

Main / Shared Settings

Settings shared by almost all types of lasers and Layer Modes, including critical settings like Speed and Power.

Line Mode

Tells your laser to trace a path along the outlines of geometry in your project.

Fill Mode

Tells your laser to etch or engrave parallel lines inside the bounds of closed shapes in your project.

Offset Fill Mode

Tells your laser to fill closed shapes with lines that follow the contour of the outer shape.

Image Mode

Works similarly to Fill Mode, but applies additional special settings to adjust output based on the pixels in your image.

Galvo-Specific Settings

Special settings that are available for users with Galvo style lasers only.

Sub-Layers

A tool for setting up and applying multiple cut/engraving settings to the same geometry or layers in your project.

Default Layer Settings

Built-in or custom-created settings stored on a per-layer basis, that you can reset to at any time.

Note

Some options in the Cut Settings Editor are hidden if you have Beginner Mode enabled.

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For more help using LightBurn, please visit our forum to talk with LightBurn staff and users, or email support.

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