Types of Sanding Blocks

There are a few different types of sanding blocks that are useful for various sanding tasks. Each type has its own advantages.

Foam Blocks
Foam blocks are inexpensive and effective for general sanding work. They come in a variety of sizes and are very versatile. The soft, pliable foam conforms well to any curves or shapes on the wood being sanded. This allows you to sand smoothly into corners and tight spaces. Foam blocks are also comfortable to hold for extended sanding sessions. However, they do wear down more quickly than harder materials and may leave swirls or textures in the wood if not used carefully.

Wood Blocks
Wood blocks are firmer than foam blocks and last longer with repeated use. They maintain their shape even after hours of sanding. Different types of wood such as poplar or maple are commonly used to make blocks. Wood blocks provide feedback about pressure points and help create a smooth, even sanded surface. The downside is they are less forgiving on curved surfaces than foam blocks. Extra care must be taken when sanding round edges.

Rigid Plastic Blocks
For flatter, more precise sanding, rigid plastic blocks work very well. Their hard, durable surface holds sandpaper flat without any give. This makes them ideal for final sanding and achieving a super-smooth finish. They can also be used to sand into corners and crevices where other block types may round off. Plastic sanding blocks are longer-lasting than foam or wood. However, they do not contour as easily to curves or odd angles.

Proper Grip for Sanding
The key to effective sanding with any type of block is maintaining the proper grip and stance. Stand with your feet shoulder-width apart for stability. Rest your free hand on the work surface for additional support. Use a grip that allows you to apply even pressure across the whole sanding surface without squeezing too tightly. This steady pressure promotes smooth sanding without swirl marks or uneven spots. Take breaks periodically to avoid fatigue in your hands and arms. Rotate between different grip positions for endurance.

Choosing the Right Grit of Sandpaper

60, 80 and 120 Grit Sandpaper
For initial sanding of bare wood or after planing or scraping, 60 or 80 grit sandpaper is commonly used. These coarse abrasives will remove material quickly to shape the wood and smooth out any tool marks or rough areas. However, they will leave deep scratches that require subsequent finer grits to eliminate. 80 and 120 grit papers follow a 60 grit initial pass. They further smooth out the coarse scratch pattern left behind.

150 to 220 Grits
Once the initial shaping is complete, 150-220 grit sandpapers polish the wood surface. These medium abrasives remove remaining 60-120 grit scratches very well. For painting or clear coating projects, 180 or 220 grit leaves a surface ready for priming or finishing. For natural wood projects, 220 grit produces an exceptionally smooth texture while preserving some of the wood grain character.

320 to 600 Grits
Very fine 320 to 600 grit papers take sanding to a super-smooth level. They are typically used for final smoothing before applying a very glossy topcoat like polyurethane or spar varnish. These ultra-fine papers will not remove much material, rather they blend away all scratch marks left by coarser grits. For rubbed finishes and hand-planed surfaces, 400 or 600 grit is commonly used as a final polishing step.

Changing Grits and Sanding Direction
For best results, change grits gradually - do not skip directly from coarse to fine papers. Always sand with the grain and change directions between each subsequent grit - either diagonally or in cross-hatched pattern. This raises fibers efficiently without leaving swirls. Start with less pressure as grits increase to avoid scratching. Changing direction and using the proper sequence will yield a satin-smooth result.

Guidelines for Sanding Common Wood

Softwoods like Pine
Softwoods containing large, semi-soft grain like pine require a lighter touch when sanding. 60 or 80 grit removes material efficiently on pine without clogging. Finish with 150 or 180 grit to polish the softer grain. Extra care must be taken not to dig in or produce uneven spots when sanding pine and other soft woods. Go with the grain using very light pressure.

Hardwoods like Oak and Maple
Harder and denser hardwoods like oak and maple require grits up through 120 or 150 for initial shaping. Their tight grain means less material removal is needed. Final sand hardwoods with 150, 220 or even 320 grit for supreme smoothness. Apply firm pressure following the grain. Despite their hardness, some sandpaper loading is normal with oily hardwoods like teak or ebony.

Preparing Pigmented or Stained Wood
For woods that will be painted, dyed, or stained, sand only as far as necessary for a product to bond smoothly - usually 150-180 grit. Finer sanding risks sanding through any character or figure in the grain. Let the topcoat emphasize the beauty of the natural grain. Stop sanding before the wood becomes perfectly smooth for best staining or glazing effects.

Proper Cleanup and Maintenance
Always blow or brush off sanding dust from blocks periodically. Clinging particles will clog abrasive surfaces more quickly. Clean blocks well with a stiff brush or rag after each use. Store