Sanding plywood edges requires careful technique to achieve a smooth finish and avoid damaging the veneer layers. The approach you take often depends on the shape of the edge – whether it's straight or curved.
Sanding Straight Plywood Edges
For straight edges, you can effectively use a common orbital sander. The key is precision and control. According to the provided reference, you should center the sanding pad on the edge and work slowly to avoid tipping the sander. This technique ensures even pressure across the entire edge thickness, preventing rounding over or uneven sanding.
Using a sanding block with sandpaper is another method for straight edges, offering manual control which can be very precise, especially for smaller projects or touch-ups.
Sanding Curved Plywood Edges
Curved plywood edges present a different challenge. While possible with hand sanding or careful use of an orbital sander, specialized tools are often recommended for better results.
- Specialized Sanders: An oscillating spindle or disc sander works great on curved edges. These tools are specifically designed for sanding curves and irregular shapes, providing a stable platform and oscillating action that helps prevent burnishing and provides a smoother finish.
- Alternative Method: If you don't have access to a spindle or disc sander, there are ways to do the job. You can try smoothing rough, curved edges using a belt sander. This method involves using a belt sander that has one side perpendicular to the platen. Carefully hold the curved edge against this perpendicular side, moving the workpiece smoothly along the curve.
General Sanding Tips
Regardless of the edge shape or tool used, it's generally advisable to start with a coarser grit sandpaper to remove saw marks and imperfections, then progress through finer grits to achieve the desired smoothness. Common grit progressions might start around 80 or 100 grit and move up to 150, 180, or even 220 grit depending on the final finish requirement.
Sanding in the direction of the wood grain is less critical on end-grain edges compared to face grain, but consistent movement and even pressure are key to preventing uneven sanding or dips in the edge.
