Both present a working face to the surface, but they mount differently and suit different machines.

A polishing pad is a moulded disc of foam, wool, or microfibre with a hook-and-loop backing. It attaches flat to the machine's backing plate and is the standard format for rotary and dual-action (random orbital) polishers. Pads come in graded densities and face patterns, so a full cutting-to-finishing sequence can be run by swapping pads.

A polishing bonnet is a fabric cover — usually wool, synthetic fleece, or microfibre — with an elasticated edge that stretches over the backing pad or the sole of an orbital machine, like a shower cap. Bonnets dominate on household orbital polishers and car-care buffers, where they are quick to fit, machine washable, and inexpensive.

For paint correction work, pads are the more precise tool: their engineered densities and consistent faces give controllable cut. Bonnets excel at spreading and buffing off waxes and sealants over large panels.

Match the pad material and density to the stage of work:

1. Heavy cutting — twisted wool pads or dense microfibre cutting pads remove sanding marks, deep swirls, and oxidation fastest. Wool runs coolest under a rotary machine; microfibre gives high cut on dual-action polishers.
2. Medium polishing — firm open-cell foam pads paired with a medium polish refine the surface after cutting and remove the haze that aggressive pads leave behind.
3. Fine finishing — soft, high-density foam finishing pads with an ultra-fine polish produce the final gloss and remove any residual micro-marring.
4. Waxing and buffing — very soft foam or fleece bonnets spread waxes and sealants and buff them to a shine without adding cut.

Manufacturers colour-code their foam ranges from aggressive to soft, but the codes are not standardised across brands — always check the maker's own scale. When in doubt, start with the least aggressive combination that might work and step up only if the defects do not clear.

Choose the pad against the machine's backing plate, not the other way round. The pad face should be slightly larger than the backing plate — typically 10–25 mm (about 1/2–1 in) of overhang in total — so the plate edge can never contact the surface, while the pad stays fully supported.

Common pairings: 75–80 mm (3 in) pads on mini/spot polishers, 125–135 mm (5–5.25 in) pads on 125 mm backing plates, and 150–180 mm (6–7 in) pads on full-size machines.

Diameter also changes how the machine behaves. Smaller pads concentrate the machine's power, cut harder, and reach curved or tight areas; larger pads cover panels faster but load dual-action machines enough to slow their orbit. Long-throw dual-action polishers in particular are designed around a specific pad size, and oversizing the pad reduces their correction ability noticeably.

Bonnets are sized by the diameter of the pad or sole they stretch over — a 150 mm bonnet fits a 150 mm plate — with the elastic edge taking up small differences.

Yes — pads and bonnets are consumables, but well-kept ones survive many uses, and cleaning them matters as much for finish quality as for economy. A pad caked with dried compound and removed paint no longer cuts predictably and can mar the surface.

During the job: clean the pad every few panels. Foam pads are cleared with a pad brush or compressed air against the spinning face; wool pads are raked with a pad spur.

After the job: wash foam and microfibre pads in warm water with a mild detergent or dedicated pad cleaner, working the residue out of the face, then rinse until the water runs clean. Machine-washing on a gentle cycle works for microfibre and most fleece bonnets. Air-dry everything face up; never use high heat, which breaks down foam cells and hook-and-loop adhesive.

Retire a pad when the foam tears, crumbles, or separates from the backing, when the face stays compacted after washing, or when a bonnet's elastic no longer grips. A worn pad costs more in rework than its replacement.

Stay inside the pad's marked maximum RPM, and work well below it for most tasks — speed generates heat, and heat is what damages both pad and paint.

Typical working ranges for a rotary polisher: 900–1,500 RPM for cutting with wool, 1,200–1,800 RPM for foam polishing, and under 1,200 RPM for finishing. Higher speeds remove defects faster but raise surface temperature quickly, especially on edges and body lines.

Dual-action polishers are set by orbit speed rather than true RPM; heavy correction is generally done at the machine's upper speed settings and finishing in the middle of the range, letting the pad and compound do the work with light, even pressure.

Warning signs of excess speed or pressure are the same on any machine: compound flashing dry immediately, the pad skipping or dusting, a hot panel surface, or foam smelling scorched. Back the speed down, keep the machine moving, and let multiple cooler passes achieve what one hot pass would risk. Bonnets on household orbital buffers run at fixed low speeds and rarely overheat.

Dedicated pads per compound stage are strongly recommended. Once a pad has carried a heavy cutting compound, abrasive residue stays lodged in its face no matter how it is wiped, and any finer polish used on that pad afterwards is contaminated back up to the coarser cut. The visible result is micro-marring that the finishing stage should have removed.

A practical minimum set for paint correction is one pad per stage — cutting, polishing, finishing — and busy detailers run several of each, swapping to a fresh pad as faces load up mid-job. Fresh pads cut cooler and more consistently, so multiples are not a luxury; a common working rule is one clean pad per two or three panels during heavy correction.

The same logic applies to bonnets: keep wax-application bonnets away from compounds entirely, and dedicate one bonnet to applying product and another to buffing off. Colour-coded pad ranges make stage discipline easy — pick a colour per stage and never cross them, even after washing.

Almost all modern pads use a hook-and-loop (Velcro-type) interface. The machine's backing plate carries the hook face; the rear of the pad carries the loop fabric. Press the pad onto the plate and it is held immediately — no adhesives, clamps, or tools.

Fitting is quick but worth doing carefully:

1. Centre the pad on the plate. An off-centre pad vibrates, wears unevenly, and can expose the plate edge on one side. Spin the machine free of the surface for a moment to check the pad runs true.
2. Press it home across the whole face so every hook engages — partial engagement lets the pad creep sideways under load.
3. Peel from one edge to remove, rather than tearing the pad straight off, which stresses the foam-to-backing bond.

Heat is the interface's enemy: an overheated pad can melt the hooks and the pad's loop fabric together, ruining both. Bonnets bypass the system entirely, stretching over the plate with an elasticated skirt — check the skirt is seated evenly all round before starting the machine.