“Sandpaper” is the familiar name for a broad family of coated abrasives. Modern products may use paper, cloth, film or another backing, with engineered abrasive grain bonded to the surface. They are supplied as sheets, discs, rolls and belts for hand use and machinery.
How a coated abrasive is constructed
The base gives the abrasive its strength, flexibility and dimensional stability. Paper and cloth are common; the best choice depends on the format and operating stress.
The first adhesive layer anchors the abrasive grain to the backing.
The cutting particles—such as aluminium oxide or silicon carbide—remove material and create the scratch pattern.
A second bond reinforces the grain and influences how the product holds up under sanding forces.
Some products include stearates, lubricants or other treatments intended for specific loading, heat or cutting conditions.
Abrasive grain
Grain determines how the abrasive cuts and renews its cutting edges. Aluminium oxide is a versatile starting point for many wood and metal applications. Silicon carbide is sharper and more brittle, and is widely considered for paint, glass, stone, non-ferrous materials and suitable wet-sanding products. Zirconia and ceramic grains are often selected for demanding stock removal where pressure and machine conditions allow them to fracture and renew.
For a fuller comparison, use the abrasive grain selection guide.
What the P grit number means
Citra Oasis uses P grit notation for coated abrasives. A lower number indicates a coarser abrasive; a higher number indicates a finer abrasive. The grading system controls particle-size distribution—it should not be interpreted simply as a count of particles per square inch.
| Relative range | Typical role | Selection caution |
|---|---|---|
| Coarse | Levelling, stripping and heavy stock removal | Can change geometry or leave deep scratches |
| Medium | General sanding and removal of coarser scratch patterns | Must still be matched to the starting surface |
| Fine | Surface refinement and preparation for many finishing steps | Finishing requirements differ by material and coating system |
| Very fine | Fine finishing, paint correction or polishing preparation | Requires the correct product construction and controlled process |
Do not choose only the final grit. A controlled progression removes the previous scratch pattern efficiently; see the grit sequence guide.
Paper versus cloth backing
Paper backing
Paper is commonly used for sheets, discs and rolls, and for many wood, paint and finishing products. Different paper weights provide different levels of flexibility and strength. A light, flexible paper and a heavy, rigid paper are not interchangeable simply because they carry the same grain and grit.
Cloth backing
Cloth generally offers greater tear strength and is widely used for sanding belts and demanding machine applications. Flexible cloth can follow contours, while heavier cloth supports aggressive cutting. Joint design and belt dimensions also matter in converted-belt performance.
Open coat, semi-open coat and closed coat
Coating density describes how much of the surface is covered with abrasive grain.
- Open coat: more space between grains can help reduce loading on soft, resinous or paint-like materials.
- Semi-open coat: balances grain coverage and chip clearance for many general applications.
- Closed coat: more cutting points cover the surface and may suit harder materials or fine, consistent cutting—provided loading is controlled.
Open coat is not automatically better than closed coat, or vice versa. The correct choice depends on swarf, loading, finish, pressure and the complete abrasive construction.
Common abrasive formats
Sanding belts
Narrow, wide and handheld-machine belts converted to specified width and length, with a joint suitable for the application.
Abrasive rolls
Paper- or cloth-backed material supplied in roll form for hand use, machinery or further conversion.
Sheets
Full or cut sheets for manual sanding, block sanding and compatible sheet sanders.
Discs
Converted for compatible tools, attachment systems, hole patterns and dust-extraction arrangements.
How to specify the right abrasive
- Name the workpiece: identify the timber, board, steel grade, paint system, stone or other material.
- Describe the operation: levelling, calibration, weld blending, paint preparation, finishing or defect correction.
- Identify the machine: include machine type, speed where known, contact system and dust extraction.
- Give the format and dimensions: belt width × length, roll width, disc diameter and hole pattern, or sheet size.
- State the current grit sequence: explain where the process starts, ends and fails.
- Define the target: removal rate, scratch finish, coating preparation or appearance requirement.
Using and storing abrasives
- Use the abrasive only on compatible materials, machines and operating conditions.
- Inspect belts, discs and sheets for damage before use; do not use damaged products.
- Use guards, extraction and personal protective equipment appropriate to the machine, workpiece dust and applicable safety instructions.
- Avoid loose clothing, jewellery and anything that can be caught by moving machinery.
- Store abrasives clean, dry and protected from extreme humidity, heat, direct sunlight and distortion.
- Follow the abrasive, machine and workpiece-material safety information; conduct a controlled trial when changing products or processes.
Start with the application, not the catalogue
A product code alone cannot define the result. Share the material, machine, dimensions, existing abrasive, grit sequence and desired finish. Browse the featured products and technical data sheets, or send those details to Citra Oasis for a suitable starting recommendation.