Define the surface and the next finish
Write down what you are sanding: bare timber, filler, a cured coating or another specified material. Then identify the next stage, such as another coat or further surface preparation. Mirka explains that grain type, backing, coating and grit all affect the abrasive’s application. The grit number is only one part of the description.
Check the abrasive maker’s material list and the coating maker’s preparation guidance. Keep recommendations for a particular finish or substrate attached to that job rather than treating them as a general sanding recipe.
Plan the progression before ordering
Mirka’s troubleshooting guidance recommends moving from coarser to finer abrasives where material removal is needed, and avoiding large jumps between grits. It notes that skipped stages can leave scratches visible after lacquer is applied. Buying only the first and last grit can therefore leave a gap in your intended process.
List the stages you actually need and compare them with the pack contents. If the correct starting or finishing grit is uncertain, seek a process recommendation for the surface rather than guessing from a familiar number. More abrasive grades are not automatically better; the useful selection is the one that covers the specified work.
Keep between-coat advice in its proper context
For intermediate sanding of paint coats on wood, Mirka gives a 240–400 grit range and cautions against removing too much of the paint layer. This is a specific application example, not a universal starting range for bare wood, filler or coating removal.
Its guidance also starts after the coating has dried. The coating’s own instructions still determine when it is ready for the next preparation step. Do not use a finer disc as a workaround for a coating that has not reached the required condition.
Investigate clogging before replacing the whole selection
Mirka identifies several checks for premature clogging: coating cure, excessively fine grit, abrasive choice and dust extraction. Reordering the same disc without checking those conditions may repeat the problem. For punched discs, the extraction holes must correspond with the backing pad; diameter alone does not establish this.
Before replenishing supplies, note which surface and stage caused the problem, the abrasive product and grit, and the pad’s hole pattern. That gives the manufacturer or supplier a more useful question than simply asking for a longer-lasting disc. Use the sander manual for operating and dust-control requirements.
Before you buy
- Match the abrasive to the substrate and preparation stage.
- Use the relevant surface or coating guidance to choose the grit sequence.
- Check that a multipack contains the grades your process needs.
- Confirm coating readiness and extraction compatibility if discs clog.
- Retain the correct diameter, fixing and hole pattern when changing abrasive products.