How to Scallop a Board Edge with a CNC Router: A Step-by-Step Expert Guide

Scalloping the edge of a wooden board adds a decorative, elegant touch to furniture, cabinetry, and custom woodworking projects. Traditionally done by hand, this process can now be executed with precision and repeatability using a CNC router. Whether you’re a seasoned woodworker or a CNC enthusiast, learning how to scallop board edges with a CNC router opens up a world of creative possibilities.

In this expert guide, we’ll walk you through the complete process of scalloping wood edges using a CNC router, from design to execution. We’ll also cover the tools, software, and techniques needed to achieve perfectly smooth, symmetrical scallops every time.

What is a Scalloped Edge?

A scalloped edge refers to a series of semi-circular or curved indentations along the edge of a wooden board. This decorative feature is often used in:

• Cabinet doors
• Table aprons
• Shelving
• Wall paneling
• Picture frames

Scalloped edges add a classic, ornamental look and can be customized in size, depth, and spacing using a CNC router.

Why Use a CNC Router for Scalloping?

Using a CNC router to scallop board edges offers several advantages over manual methods:

• Precision – Perfectly symmetrical and repeatable scallops
• Speed – Faster than hand-carving or routing with jigs
• Customization – Easy to adjust depth, radius, and spacing
• Consistency – Uniform results across multiple boards

Step-by-Step: How to Scallop Board Edges with a CNC Router

1. Design Preparation

• CAD Software: Use CAD software (e.g., Vectric Aspire, Fusion 360) to design the scalloped edge.
  • Draw the board outline.
  • Create evenly spaced semicircles or curves along the edge. For uniformity, use tools like “Array” or “Pattern” to replicate the scallop shape.
  • Ensure scallop spacing matches the desired aesthetic (e.g., 2″ wide scallops on a 24″ board = 12 scallops).

2. Tool Selection

• Ball Nose End Mill: Ideal for smooth curves (e.g., 1/4″ or 1/2″ diameter). The radius of the bit determines the scallop depth.
• Alternative: A down-cut spiral bit minimizes tear-out on the top edge.

3. CAM Setup

• Import Design: Load the scallop vector into CAM software.
• Toolpath Strategy:
  • Use a 2D Profile Toolpath to follow the scalloped vector.
  • Set Cut Depth: Typically 1/4″ to 1/2″, depending on material thickness and desired effect.
  • Climb Milling: For cleaner edges on wood.
  • Multiple Passes: If cutting deep, use step-down increments (e.g., 0.1″ per pass).

4. Material Setup

• Secure the Board: Use clamps or a vacuum table, ensuring no interference with the toolpath.
• Orientation: Align the board so the edge to be scalloped is accessible. Set the origin (X/Y/Z) at a corner or edge.

5. CNC Parameters

• Feed Rate and RPM:
  • Softwoods: ~100-150 IPM feed, 12,000-18,000 RPM.
  • Hardwoods: ~60-100 IPM feed, 10,000-16,000 RPM.
• Depth of Cut: Adjust based on material and bit size (e.g., 1/4″ depth for a 1/2″ ball nose bit).

6. Safety Checks

• Inspect tool clamping, workpiece security, and clearances.
• Wear safety gear and perform a dry run.

7. Execution

• Run the CNC job, monitoring for issues like chatter or burning.

8. Post-Processing

• Sanding: Smooth any rough edges with 120-220 grit sandpaper.
• Inspection: Verify scallop consistency and depth.

Tips for Success

• Test on Scrap: Validate toolpaths on a spare piece.
• Grain Direction: Cut with the grain to reduce tear-out.
• Dust Management: Use a vacuum to keep the workspace clear.

Final Thoughts

Scalloping a board edge with a CNC router is a fantastic way to add artistry and craftsmanship to your woodworking projects. With the right tools, design, and technique, you can create elegant, professional-looking scalloped edges that elevate the aesthetic of any piece.

Whether you’re working on custom furniture, decorative trim, or creative art pieces, mastering this technique will set your work apart.