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Cutout

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Marius Stanciu edited this page Oct 29, 2026 · 1 revision

Cutout creates a Geometry object with the toolpaths that cut a PCB out of the surrounding material. It can leave gaps (also called tabs or bridges) that keep the board connected to the panel. It can also cut by drilling along a line. Use it as the last operation of a PCB job, after the copper is done.

Where to find it

  • Plugins menu: select Cutout (shortcut Alt+X).
  • Plugin Toolbar: click Cutout.
  • The plugin panel opens in a new tab of the side panel. The tab shows the plugin name. Select the outline object in the Project tab, or choose it in the Source Object combo box.

Screenshot placeholder: images/Cutout-1.png - the whole Cutout panel in Advanced Mode, with the Tool, Parameters, Gaps and Cut by Drilling sections visible.

Quick start

  1. Load the board outline as a Gerber file with Importing Files. A Gerber file with the outline (Edge.Cuts) works best.
  2. Select the outline in the Source Object combo box. Set Type to Gerber.
  3. Keep Kind on Single for one PCB. Use Panel for a panel of many PCBs.
  4. Enter the cut width in Tool Dia, such as 2.4 (mm, or inch in an inch project).
  5. Set Cut Z (negative) and, if needed, Multi-Depth with Depth.
  6. In Gaps, set Size and Gaps to the number of bridges you want. The default is 4.
  7. Click Generate Geometry. A new Geometry object appears in the Project tab.

Screenshot placeholder: images/Cutout-2.png - the canvas with the cutout path around a PCB and the gaps shown as breaks in the path.

Parameters

Source Object

Parameter Description Default
Kind (radio) Single: the object is one PCB outline. Panel: the object is a panel made of many individual PCB outlines. Single (tools_cutout_kind)
Type (radio) Gerber: the outline is a Gerber object. The cut gets the cutter radius compensation. Geometry: the outline is a Geometry object. Its paths are already machining centrelines, so they get no radius compensation. —
Source Object (combo box) The object to cut out. Its kind follows Type. -

Cutout Tool

Parameter Description Default
Tool Dia The diameter of the tool that cuts out the PCB. 2.4 (tools_cutout_tooldia)
Search and Add Adds a tool with the diameter of Tool Dia to the tool table. A background search in the Tools Database looks for a matching tool. If nothing is found, a default tool is added. Hidden in Beginner Mode. -
Pick from DB Opens the Tools Database and adds the tool you select. Hidden in Beginner Mode. -

Parameters

Parameter Description Default
Convex Shape Creates a convex shape around the entire PCB. Used only when the source type is Gerber. Hidden in Beginner Mode. Off (tools_cutout_convexshape)
Cut Z The cutting depth, as a negative value, below the copper surface. -1.8 (tools_cutout_z)
Multi-Depth (checkbox) When checked, the cut is made in several passes. Each pass cuts one Depth until Cut Z is reached. On (tools_cutout_mdepth)
Depth (field, for Multi-Depth) The depth of each pass, as a positive value. 0.6 (tools_cutout_depthperpass)
Margin The margin over the bounds. A positive value moves the cutout further from the actual PCB border. 0.1 (tools_cutout_margin)
Source is board outline Check it only for a board outline file (profile, Edge.Cuts, GKO or GM1). Every hole and every inner closed contour in it is then cut as a cutout. This setting is not saved. It is unchecked again when the object changes. Off
Cut inside contours Cuts the slots and the inner contours of the board outline, as well as the outer edge. Active only when the source is a board outline and the shape is Any. Off (tools_cutout_inner)
Gaps on inner contours Adds the gaps, thin gaps and mouse bites also to the inner contours. When off, the inner contours are cut without gaps. Active only with Cut inside contours, in Automatic mode. Off (tools_cutout_inner_gaps)

Gaps

Parameter Description Default
Size The length of each gap (bridge) measured along the contour. It is the uncut part that keeps the board connected to the panel. 4 (tools_cutout_gapsize)
Type (combo box) The type of gap. See the choices below. Bridge
Depth (field, for Thin) The depth of a thin gap. It is a negative Z value, not the thickness of the material left. -1.0 (tools_cutout_gap_depth)
Tool Dia (field, for Mouse Bytes) The drill hole diameter of each mouse bite. 0.6 (tools_cutout_mb_dia)
Spacing (field, for Mouse Bytes) The edge-to-edge distance between two mouse-bite holes. 0.3 (tools_cutout_mb_spacing)
Automatic / Manual (radio) Automatic: gaps are placed by the Gaps pattern below. Manual: you place each gap on the canvas. Automatic
Gaps (combo box, Automatic only) The number and place of the gaps. See the choices below. 4
Shape (checkbox) When checked, the cutout shape is rectangular. When unchecked, the shape is Any. Any (off)

Type choices:

  • Bridge: the cutout is interrupted by bridges.
  • Thin: the same as Bridge, but each gap is thinner. The gap is partly milled to the Depth.
  • Mouse Bytes: mouse bites. The same as Bridge, but covered with drill holes.

Gaps choices (Automatic mode):

  • None: no gaps.
  • LR: one gap on the left side and one on the right side, at the middle height.
  • TB: one gap on the top side and one on the bottom side, at the middle width.
  • 4: two LR gaps and two TB gaps. That is four gaps.
  • 2LR: two gaps on each side, at one quarter and three quarters of the height.
  • 2TB: two gaps on the top and two on the bottom, at one quarter and three quarters of the width.
  • 8: the 2LR and 2TB gaps together. That is eight gaps, the maximum.

Manual gaps

These controls appear when Manual is selected.

Parameter Description Default
Big cursor (checkbox) Uses a big cursor when you add manual gaps. On (tools_cutout_big_cursor)
Manual cutout Geometry (combo box) The Geometry object used for the manual cutout. -
Manual Geometry (button) Creates a Geometry to use as the cutout. -
Gaps (button) Starts the manual gap mode on the selected Geometry. See the steps below. -

Manual gap mode:

  • Left click a contour of the selected Geometry to add a bridge.
  • Click a bridge placed in this session to select it. Drag its orange grip to preview a move. Release to apply.
  • Click a destination, or press Delete, to remove the selected bridge.
  • Right click keeps the current bridges and finishes.
  • Escape restores the object to the state before this session.
  • Bridges from completed sessions cannot be selected or edited.

Generate

Parameter Description Default
Generate Geometry Creates the cutout Geometry with the gaps (Automatic mode). -
Manual Geometry and Gaps Shown in Manual mode only, see above. -

Cut by Drilling

This section creates a series of drill holes along a Geometry line.

Parameter Description Default
Geometry (combo box) The Geometry object with the line to follow. -
Drill Dia The diameter of the drill that cuts by drilling. 1.0 (tools_cutout_drill_dia)
Pitch The distance between the centres of two neighbouring drill holes. 1.0 (tools_cutout_drill_pitch)
Margin The margin over the bounds. A positive value moves the cut further from the actual PCB border. 0.0 (tools_cutout_drill_margin)
Cut by Drilling (button) Creates the series of drill holes. -

Reset Tool

Parameter Description Default
Reset Tool Resets the parameters of the cutout to their defaults. -

Advanced

How the gaps are placed

The anchor points of the gaps are on the bounding box of the contour:

  • LR and TB put the gaps at the middle of the sides.
  • 2LR and 2TB put the gaps at one quarter and three quarters of each side.
  • 4 and 8 combine these patterns.

Each gap is Size long along the contour, centred on its anchor point. The rest of the contour is cut.

A cutout with gaps fails in these cases. The message tells you why:

  • The gaps do not fit on the contour.
  • Two gaps overlap or touch.
  • The gaps would remove the whole contour.

Change Size, the Gaps choice or the object, then generate again.

Thin gaps

Depth is a negative Z value. It is not the remaining material. The rule is:

Cut Z < Depth < 0

Example: Cut Z -1.8 and Depth -1.0 are valid. A Depth of 0 gives a full-thickness bridge, and no thin-gap tool is created.

Mouse bites

Each mouse bite is a drill hole. The centre-to-centre pitch of the holes is:

pitch = Tool Dia + Spacing

With the defaults, the pitch is 0.6 + 0.3 = 0.9.

Board outline and inner contours

For a board outline, Source is board outline cuts every hole and every inner closed contour. Use Cut inside contours to cut the slots and inner contours too. This needs the shape to be Any. Gaps on inner contours adds gaps to these inner contours. It is available only in Automatic mode.

Rectangular shape

When Shape is checked, the cut is rectangular. The icons of Generate Geometry and Manual Geometry change to match the shape.

Beginner Mode

Beginner Mode hides these controls: Convex Shape, Search and Add, Pick from DB, Type of the gaps, the Automatic / Manual choice, the separator line, and the Cut by Drilling section. Switching the mode also sets the cutout type to Automatic. The level button is at the top of the panel, and the permanent setting is in Preferences.

Tcl

The Tcl command is cutout (also geocutout). Its options are: name, type, dia, margin, gapsize, gaps and outname. See Tcl Command Reference.

See also

FlatCAM Evo Manual · Source code · Report a problem · MIT license

FlatCAM Evo Manual

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