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Cut a pocket from a DXF

A DXF is how a drawing usually arrives from another CAD program, and a pocket is the first thing most people want to cut from one: clear out the inside of a closed shape to a set depth. There is one real trap, which is leaving a boss standing in the middle. This guide brings a DXF in, pockets it, and shows both the right way and the way that quietly cuts the boss away.

Open RapidCAMNothing to install, no account.

  1. Bring the DXF in

    Start a New Project for your blank (here 100 × 70 mm, 12 mm thick), then drag the DXF onto the RapidCAM window. The example is a closed 80 × 50 mm rectangle with a 16 mm circle in the middle of it; use your own drawing if it has a closed outline, ideally with something inside it.

    If the file records its units, it simply arrives. If it does not, RapidCAM asks rather than guessing, and says what each answer would mean:

    No units in the file: the dialog shows the size each answer would import at. Pick the one that looks like your part.
    A dialog titled What units is this DXF in, saying the file doesn't record its units and the drawing measures 80 by 50 drawing units, with Millimetres (recommended, imports at 80 by 50 millimetres) and Inches (imports at 2032 by 1270 millimetres)

    Here the drawing is 80 × 50 units, so millimetres gives a part that fits the blank and inches gives one two metres wide. The drawing’s own zero lands on the stock’s front-left corner, and this rectangle was drawn 10 mm in from it, so there are 10 mm of wall all round.

    Imported, with 10 mm of wall all round.
    The imported rectangle and circle inside the lighter 100 by 70 millimetre stock, both selected, with 10 millimetres of stock showing on every side

    The import arrives as a group named after the file. Press Ungroup in the Properties panel so each shape can be picked on its own.

  2. Add the pocket, and choose the area

    Open the Toolpaths tab and press + Add Toolpath. Set Type to Pocket (interior clear): it clears everything inside a closed shape, down to depth, in stepped passes.

    What to cut has two answers, and they are not the same. To leave the circle standing as a boss, choose Click inside an area (flood fill) and click on the canvas between the wall and the circle. The area shades, and the list reads Area 1 — 80.00 × 50.00 — 1 island: anything enclosed inside the area you click is left standing.

    Flood fill: the shaded area is what gets cleared, and the circle is its island.
    The Add Toolpath dialog for a pocket with What to cut set to Click inside an area, an orange shaded area on the canvas around a circle, and the list reading Area 1, 80 by 50, 1 island

  3. Set the depth

    A new toolpath’s Depth starts at 3 mm. For a pocket you choose how deep: here 6 mm, half of the 12 mm blank, so the floor is 6 mm thick. (⊥ stock beside the field sets the depth to the whole thickness, which is right for cutting a part out and wrong for a pocket.) The rest can stay as it is: Stepdown 1.5 mm, Stepover 0.4 (40% of the tool diameter) and Clearing set to Offset (contour-parallel) with the default 6 mm end mill. Press Apply.

  4. The trap: picking both outlines

    It is tempting to select the rectangle and the circle and leave What to cut on Pick the outlines yourself, because that is what you drew. It cuts the circle away. Picked outlines are each a shape to pocket, so the circle becomes a second pocket, not an island. We checked by sweeping the cutter over the floor of the exported program: with both outlines picked the circle’s whole area was cleared, the same as with the rectangle alone, and with flood fill it was left standing.

    RapidCAM now says so in the export check, which is the preview you see when you press Generate G-code. Its warning names the toolpath and the way out, and the preview of the path shows why: the rings run straight across the circle.

    Both outlines picked: the rings cross the circle, and the pre-flight warns that it is cleared too.
    The Export preview showing concentric rectangular rings that pass through a circle in the middle, and a warning that one picked outline lies inside another so it is cleared too instead of being left standing as an island

  5. Look at it, then export

    Press 3D and drag in the view to tilt it until you are looking down into the pocket. The circle stands in it as an island, with the cutter having gone around it.

    The flood-fill pocket from above: the circle is left standing.
    The 3D preview looking down into the rectangular pocket, with a round island standing in the middle of the floor

    Press Generate G-code. This job is about nine minutes, and the only note on a fresh profile is the tool-change one. Export saves the .nc file; set your zero first (Set your zero).

    Before you run it: clamp the blank so nothing is in the cutter’s way, check the depth against your real material thickness, and stay with the machine while it cuts.

Open RapidCAMNext: hold the part down with tabs

Checked against RapidCAM on 2026-10-05. If something here no longer matches what you see, the app has changed and this guide is behind: please tell us.