Sanding blocks and paper

This page has safety advice that hasn't yet been checked by our safety reviewer. Treat it as general guidance, and follow your game's, venue's or product's own safety rules first.

A guide to choosing and using sanding blocks and sandpaper for smoothing cosplay props and 3D-printed parts, aimed at beginners.

Sanding blocks and sandpaper are among the most fundamental finishing tools in a cosplayer's kit. Loose sandpaper can fold, slip, or cut unevenly, so wrapping a sheet around a firm block — whether a purpose-made rubber or foam block, a scrap of wood, or even a small piece of dense packing foam — gives you a flat, consistent surface to work against. This makes it much easier to smooth flat panels, blend filler putty, and knock down the layer lines that 3D-printed parts are known for. Sandpaper is graded by grit number: lower numbers such as 80 or 120 are coarser and remove material quickly, while higher numbers like 400, 800, or 2000 cut much more finely and leave a progressively smoother surface. A typical workflow moves from a lower grit to gradually higher grits, with each pass erasing the scratches left by the one before. For 3D prints, many makers start somewhere in the low-to-mid range to level the ridges, then work upward through finer grits before applying primer. Wet-and-dry sandpaper — used with a little water — is especially popular for the finer stages because the water carries away debris and helps the paper last longer without clogging. Different backing materials suit different jobs. Standard paper-backed sheets are fine for dry sanding and general shaping. Cloth-backed abrasives are more flexible and durable, which helps on curved surfaces. Foam-backed sanding pads conform to gentle curves even better and are worth keeping on hand for organic shapes like armour shoulder pieces or helmets. Sponge sanding blocks sold in hardware and hobby shops often come in multi-packs covering several grit ranges, which is a convenient starting point. Safety with sanding is easy to overlook but genuinely important. Sanding — especially on resin prints, filler primers, or any painted surface — creates fine dust that you should not breathe in. Work in a well-ventilated area or outdoors when possible, and wear a dust mask or respirator rated for fine particulates. Safety glasses protect your eyes from stray grit. Younger makers should have an adult present, particularly when sanding resins or any material whose dust composition is uncertain. Check any filler or primer product's own data sheet for specific hazard information before sanding it.