June 25, 2024 3 min read

The beauty of live edge slabs lies in their raw, natural charm, which can add a unique aesthetic to any woodworking project. However, working with these pieces requires a specific skill set, particularly when it comes to flattening. Flattening is crucial for ensuring stability and usability, transforming a rough, uneven slab into a perfectly level piece of wood.

Understanding the Importance of a Level Surface

The Foundation of Quality Woodworking

Before diving into the flattening process, it's essential to understand why achieving a flat surface is paramount. A level slab ensures that your finished product, be it a table, countertop, or shelf, sits evenly and performs its function without any wobble or instability. It also provides a smooth base for further detailing, finishing, and aesthetic enhancements.

Assessing the Slab's Condition

Every live edge slab is unique, with its own set of knots, curves, and warps. Assessing the slab's initial condition is the first step in the flattening process. This involves checking for any significant dips, rises, or areas of concern that might affect the final outcome.

The Flattening Process: Step by Step

Preparing Your Workspace

  1. Secure Your Slab: Begin by securing the live edge slab to your workbench to prevent any movement during the flattening process. Use clamps or a custom jig for a firm hold.
  2. Choose the Right Tools: Selecting appropriate tools is critical. For most DIY enthusiasts, a router with a flattening bit and a sled setup is an ideal choice. Alternatively, hand planes can be used, though they require more skill and effort.

Flattening with a Router

  1. Setting Up the Sled: Build or set up a sled that allows your router to glide smoothly over the slab. The sled should span the entire width of the slab and provide a steady base for the router.
  2. Routing in Passes: Adjust the router to remove minimal material with each pass. This gradual approach helps maintain control and prevents gouging the wood. Move in a consistent pattern, overlapping each pass slightly.

Flattening by Hand

  1. Choosing the Right Plane: A #5 jack plane or a larger jointer plane is ideal for this task. Make sure the plane is sharp and properly adjusted.
  2. Technique Matters: Begin by identifying high spots on the slab. Use the plane in controlled strokes, focusing on these areas. Regularly check for levelness using a straight edge or level.

Post-Flattening Considerations

Sanding and Smoothing

Once the live edge piece is satisfactorily flat, the next step is sanding. Start with a coarse grit and gradually move to finer grits. This not only smooths the surface but also prepares it for finishing.

Applying Finish

Choosing the right finish can enhance the natural beauty of the wood. Options range from oils and waxes, which provide a more natural look, to lacquers and varnishes for a more polished appearance. Application should be even and consistent, following the manufacturer's instructions.


The process of flattening a live edge slab, though challenging, is incredibly rewarding. It allows woodworkers to showcase the inherent beauty of the wood while transforming it into a functional and aesthetically pleasing piece. With patience, precision, and the right techniques, anyone can master this essential woodworking skill. For further assistance or inquiries, feel free to contact KC Custom Hardwoods today. We are always here to help guide you through your woodworking journey.