How do Keep-Out Zones work in VCarve Pro & Aspire to prevent the tool from crashing into clamps and fixtures during rapid moves?

Overview

Keep-Out Zones are a V12 feature that lets you mark areas of the material where the tool should not pass through or over. They are designed to represent clamps, screws, vacuum pods, jigs, and any other fixture that protrudes above the material surface and could damage a tool.

Before V12, the only protection against clamp collisions was raising the global Clearance (Z1) gap high enough to clear every obstacle, which added time to jobs with many rapid moves. Keep-Out Zones let you mark the obstacles instead. Both VCarve Pro and Aspire include the feature.

How They Work

Keep-Out Zones operate on Clearance Height moves: the moves the tool makes between toolpaths when it travels from one cutting area to another.

Important limitation: Keep-Out Zones do NOT protect the tool's move to the Home position at the end of the job. Once the last toolpath is finished, the tool rises to the Safe Z Home height, which is the "Z Gap Above Material" in Material Setup, and travels to Home. Set that gap high enough to clear every clamp on the bed.

There is no obstacle height setting. The zone is a footprint only. Do not assume the software knows how tall a clamp is.

Setting Up Keep-Out Zones

1. Draw closed vectors in the 2D view representing the footprint of each obstacle (clamp, screw, vacuum cup, etc.). Vectors must be closed: if a vector is open, close or join it first using the close or join vector options in the Design tab
2. Select the closed vector(s) in the 2D view
3. Open the Keep-Out Zones form from the Toolpaths tab
4. Enter a Clearance value if you need the zone to extend beyond the area covered by the selected vectors. Use this instead of redrawing the vectors larger, so the zone covers the tool radius and a safety margin
5. Click Create from Selection. The zones are created from the selected vectors with the Clearance offset applied
6. Zones appear as a distinct overlay in the 2D view
7. Use Clear Zones to remove all currently active zones

Once created, Keep-Out Zones are not linked to the vectors used to make them. They stay even if you delete the vectors, so use Clear Zones if the clamp layout changes.

Key Settings and Tips

Clearance: Make zones larger than the physical obstacle. A zone with no clearance covers only the vector outline, so add enough Clearance for the tool radius plus a margin.

Safe Z Home: Even with Keep-Out Zones, set the Z Gap Above Material high enough to clear the tallest obstacle on the bed for the end-of-job move to Home.

Toolpath warning: If you calculate a toolpath that intersects a Keep-Out Zone, the software shows a warning in the 3D view and a warning popup. Do not ignore it: move the clamp, change the toolpath boundaries, or reposition the part.

Rapid Plunge gap: To offset the time cost of a high Clearance (Z1) gap, set the Plunge (Z2) gap in Material Setup to a smaller value. The tool then plunges at rapid rate down to the Plunge (Z2) height and only switches to the plunge feed rate for the final approach. Some engraving machines cannot use this feature.

Post-processor note: When Keep-Out Zones are used, the post-processor's standard RAPID_MOVE section is ignored and STRAIGHT_RAPID_MOVE is used instead. Some machines do not interpolate G0 moves and need G1 with a feed rate there. Check that your post-processor has a suitable STRAIGHT_RAPID_MOVE line before cutting.

V11.5 and earlier: Keep-Out Zones did not exist. The workaround was to raise the clearance gap globally, or to reorder and group toolpaths to avoid rapids through obstacle areas.

Practical Setup Workflow

1. Lay out your material in the job
2. Decide where clamps and fixtures will sit on the bed
3. Draw closed rectangles or circles over each clamp position in the 2D view
4. Select the clamp vectors, set a Clearance value, and click Create from Selection
5. Set a moderate Clearance (Z1) gap (enough to clear the material)
6. Set Safe Z Home high enough to clear everything for the return move
7. Calculate and preview the toolpaths. Check the 3D view for any zone warning, and test the first run with the spindle off and the tool well above the work