How does the Pocket Toolpath work in VCarve Pro & Aspire: Offset vs Raster, multiple clearance tools, profile pass, and pass depth control?

Overview

The Pocket Toolpath clears all material inside one or more closed vector boundaries to a specified depth, creating a flat-bottomed recess. It is one of the most versatile toolpaths, used for sign letter pockets, inset panels, fixtures, box interiors, and clearing background material from carved signs. It is available in both VCarve Pro and Aspire.

Two Fill Strategies

Offset

Cuts in offset paths that follow the shape of the vector boundary. Cut Direction can be Climb (CCW) or Conventional (CW).

Best for: Irregular shapes, pockets with curved walls, shapes where following the contour gives better surface quality.

Tail moves: When the stepover is greater than 50% of the tool diameter, the software automatically adds small tail moves at corners to ensure no material is left.

Raster

Cuts in parallel back-and-forth lines across the pocket at a specified angle.

Best for: Large flat areas where parallel lines are faster. Common for background clearing on sign panels.

Raster Angle: Between 0 and 90°. 0° is parallel to the X axis; 90° is parallel to the Y axis.

Profile Pass for Raster: Raster needs a cleanup pass for clean walls. Options: First (profile before rastering), Last (after rastering), or No Profile Pass (you must calculate a profile pass manually). With multiple tools, choosing No Profile Pass makes the next tool machine areas that the profile pass would otherwise have cleaned up. Cut Direction applies only to the profile pass.

Multiple Clearance Tools

Add multiple tools in sequence, large tool first and smaller tools after:

1. Large tool (e.g., 1/2" end mill) clears the bulk
2. Smaller tool (e.g., 1/4" end mill) only runs in areas the large tool couldn't reach
3. An allowance is always left for the final tool

The tool order in the list should match the order they run on the machine. Use case: complex pockets with both open areas and tight corners.

Pass Depth Control

Default: The software may adjust the step down by up to 15% in either direction to reduce the total number of passes. This is usually desirable for efficiency.

Maintain Exact Step Depth: Prevents the software from varying the step. Required when cutting laminated materials where exact layer depths matter.

Edit Passes manually: Click Edit Passes to set custom depths for each individual pass.

Pocket Allowance

Positive Allowance: Leaves a thin wall of material around the edge of the pocket (pocket undersized), applied equally to each side. Use before a Profile Toolpath cleanup pass for clean vertical walls.

Negative Allowance: Cuts additional material, enlarging the pocket slightly beyond the vector.

Clean pocket wall workflow:

1. Set Pocket Allowance = 0.02" positive
2. Calculate the Pocket toolpath. It clears the bulk and leaves 0.02" on the walls
3. Create a Profile Toolpath (Inside) at full depth with zero allowance
4. The profile pass trims the walls to exact size, eliminating chatter marks

Nested Vectors (Islands)

For nested shapes (outer boundary + inner islands), the software pockets the area between them, leaving inner shapes raised. Used for letter pockets in layered signs.

Start Depth

For surface pockets: 0. For pockets inside an existing pocket: enter the outer pocket depth as Start Depth. Total depth = Start Depth + Cut Depth.