Automotive Sandpaper Grit Chart: What Grit to Use at Every Stage of a Car Paint Job

A good automotive paint job is built on the sanding work underneath it. The correct sandpaper grit removes defects and creates a surface that the next material can grip. The wrong grit can leave scratches beneath the paint, cut through panel edges, create waves in body filler, or reduce adhesion between coatings.

The most important rule is simple: lower grit numbers cut more aggressively, while higher numbers produce finer scratches. The correct starting and finishing grit depends on what you are sanding and what will be applied next.

Use the chart below as a general starting point. Always check the technical data sheet for your specific body filler, primer, sealer, basecoat, single-stage paint, or clearcoat before sanding. Product requirements take priority over any general grit recommendation.

Quick Automotive Sandpaper Grit Chart

Sandpaper grit	Common automotive use
P40–P80	Heavy paint removal, rust removal, weld cleanup, and initial metalwork
P80–P120	Shaping body filler and leveling rough repairs
P120–P180	Refining body filler and removing coarse sanding scratches
P180–P220	Feather-edging old paint and preparing repairs for high-build primer
P240–P320	Final filler refinement, primer preparation, and removing P180 scratches
P320–P400	Blocking and refining primer-surfacer
P400–P600	Final primer sanding before many solid colors, basecoats, and single-stage paints
P600–P800	Final preparation for many metallic or pearl colors, blend areas, and sound existing finishes
P1000–P1500	Leveling defects or texture in fully cured clearcoat
P2000–P3000	Refining clearcoat sanding scratches before compounding
P5000	Final clearcoat refinement to shorten compounding time

 

These ranges overlap because paint systems differ. A solid-color single-stage urethane may require a different final scratch than a metallic basecoat. The condition of the panel, whether a sealer will be applied, and whether sanding is performed by hand or with a dual-action sander also affect the correct choice.

P40–P80: Removing Paint, Rust, and Heavy Damage

P40 to P80 abrasives are used for aggressive material removal. They can strip old coatings, remove surface rust, clean up repair areas, and prepare damaged metal for further work.

For severe coating removal, a product such as the 3M Green Corps 00524 40-Grit Abrasive Disc cuts quickly. However, P40 leaves deep scratches and should not be used across an entire undamaged panel simply to prepare it for paint. On modern sheet metal, aggressive sanding also increases the risk of thinning or distorting the panel.

P80 is a more common starting point for localized collision repair and body-filler work. High Teck 80-Grit PSA Sanding Discs can be used for removing coatings and establishing the initial shape of a repair.

Before sanding, clean the surface with a dedicated automotive cleaner such as Grow Automotive 1705 Grease, Wax and Silicone Remover. Sanding a contaminated panel can drive wax, silicone, grease, or road residue into the existing finish and cause adhesion problems later.

P80–P180: Shaping and Refining Body Filler

Fresh body filler usually requires more than one sanding step. Start with a grit aggressive enough to establish the repair shape, then progress to a finer grit that removes the previous scratches.

A common progression is:

1. P80 for the initial shape.

2. P120 or P150 to refine the surface.

3. P180 to remove the remaining coarse scratches and prepare for primer, when permitted by the primer manufacturer.

Roberlo Maxifill Universal Light Body Filler is formulated for fast drying and easy sanding, but good technique remains essential. Avoid pushing excessively hard on the sanding block. Heavy pressure can flex the panel, dig low spots into the filler, and make the repair appear straight while pressure is applied but wavy after sanding stops.

For the refinement stage, High Teck 180-Grit PSA Sanding Discs provide a useful transition between coarse filler shaping and primer preparation.

Use the longest sanding block that fits the repair. Long blocks bridge low spots and level high spots more effectively than sanding with fingertips. The Dura-Block AF44HL Hook-and-Loop Sanding Block Kit provides multiple shapes for flat panels, contours, and tighter repair areas.

P180–P320: Feather-Edging and Preparing for Primer

Feather-edging creates a smooth transition between the repair and the surrounding factory finish. Each coating layer should taper gradually without leaving a hard edge that can show through the finished paint.

P180 or P220 can be used to begin feather-edging, depending on the coating and repair. Follow with P240 or P320 to remove the coarser scratch pattern. High Teck 220-Grit PSA Sanding Discs and High Teck 320-Grit Hook-and-Loop Sanding Discs provide a practical two-step progression for this stage.

Do not assume that a thick coat of primer will hide every sanding mark. Primer-surfacer can fill a controlled scratch pattern, but deep P80 scratches left outside the filler repair may shrink back and become visible after the vehicle has been painted.

Before applying primer:

• Remove all coarse scratches outside the intended repair area.

• Eliminate glossy edges that could reduce adhesion.

• Blow off sanding dust and clean the panel correctly.

• Confirm that the final grit is approved for the primer being used.

A high-build product such as the High Teck 7330 Gray 2K Urethane Primer Kit can help level properly prepared repairs. Primer is not a substitute for straight bodywork or a correct sanding sequence.

P320–P600: Blocking Primer Before Paint

Once the primer-surfacer has cured according to its technical data sheet, it must be leveled and refined before color is applied.

Start with a grit that can remove texture and minor surface variation without cutting through the primer too quickly. P320 or P400 is commonly used for initial primer blocking. A guide coat helps reveal low spots, pinholes, scratches, and texture that are difficult to see on a uniform primer surface.

High Teck 400-Grit Hook-and-Loop Sanding Discs are suitable for refining primer with a DA sander. Flat repair areas should still be checked with a block because a soft DA interface can follow waves instead of removing them.

After the panel is straight, refine the surface with the final grit required by the paint system. P400 to P600 is common before many automotive topcoats. High Teck 600-Grit PSA Sanding Discs can remove the P400 scratch pattern and leave a finer surface for color application.

Use extra care on panel edges, peaks, and body lines. These areas have less coating build and are easy to sand through. Sand them by hand with light pressure, and avoid holding a DA sander over an edge.

P600–P800: Metallic Colors, Pearl Colors, and Blend Areas

Metallic and pearl colors tend to reveal coarse sanding scratches more readily than many solid colors. Some paint systems therefore specify P600 or P800 for final preparation, especially in blend areas or over a sound existing finish.

High Teck 800-Grit Hook-and-Loop Sanding Discs can create a fine, uniform scratch where the coating system permits P800 preparation.

Do not automatically use the finest paper available. A surface can become too smooth for the next coating to achieve reliable mechanical adhesion. Follow the basecoat, single-stage, or sealer technical data sheet and make sure every glossy area has been prepared, including edges and recesses.

If a sealer will be applied, its approved substrate and sanding requirements may differ from those of basecoat applied directly over sanded primer. Confirm the complete system rather than choosing the final grit from the color alone.

P1000–P1500: Leveling Defects in Cured Clearcoat

Fine wet sanding is performed after the clearcoat has cured sufficiently. It can level dust nibs, small runs, light orange peel, and other surface texture before compounding.

P1000 or P1200 cuts quickly but also removes clearcoat quickly. These grits should be reserved for defects that genuinely require aggressive leveling and for finishes with enough clearcoat film build to be corrected safely. P1500 is a more controlled starting point for many general paint-finishing jobs.

Never sand through the clearcoat and into the basecoat. A sand-through normally requires repainting the affected area. Also avoid sanding freshly applied basecoat as if it were clearcoat. If basecoat contains a defect, follow the paint manufacturer's procedure for correcting and recoating it before clear is applied.

When wet sanding:

• Keep the surface and abrasive clean.

• Use a suitable interface pad or block.

• Sand only until the defect is level.

• Dry the area frequently to inspect progress.

• Stay away from edges and sharp body lines.

P2000–P5000: Refining Clearcoat Before Polishing

After the defect has been leveled, finer abrasives remove the previous sanding scratches and reduce the amount of compounding required.

A typical finishing progression is P1500, P2000, P3000, and then P5000. The correct starting point depends on the severity of the defect and the clearcoat manufacturer's finishing recommendations.

The 3M 30666 Purple Finishing Film Disc in P2000 is designed for leveling and refining paint defects. Follow it with the 3M 02085 Trizact 3000-Grit Foam Discs to reduce the P2000 scratch pattern. For further refinement, 3M 30662 Trizact 5000-Grit Foam Discs can leave a surface that requires less aggressive compounding.

Refining to a finer grit does not eliminate polishing. Sanded clearcoat must still be compounded and polished to restore full gloss. The 3M Buff and Polish Full Bundle Kit combines compound, machine polish, ultrafine polish, and matching pads for a complete finishing sequence.

Should You Sand by Hand or With a DA Sander?

Both methods belong in a complete automotive sanding process.

Use a DA sander for:

-Removing coatings from broad areas.

-Initial body-filler shaping.

-Feather-edging repairs.

-Refining primer across larger surfaces.

-Producing a consistent scratch efficiently.

Keep the sander flat and moving. Tilting the pad or concentrating on one spot can create gouges, pigtails, and uneven surfaces.

Use a sanding block for:

-Straightening body filler.

-Leveling primer on flat panels.

-Revealing high and low spots.

-Sanding near body lines with better control.

Hand-sand carefully around:

-Panel edges.

-Door-handle recesses.

-Curves and narrow contours.

-Sharp peaks and stamped body lines.

The Dura-Block AF4401 PSA Sanding Block is compact enough for smaller repairs while still distributing pressure more evenly than fingertips.

Wet Sanding Versus Dry Sanding

Dry sanding is normally preferred for body filler, bare metal, and much of the primer preparation process. It makes the scratch pattern easier to inspect and prevents water from entering porous filler, exposed metal, seams, or pinholes. Dust extraction also helps keep the panel and work area cleaner.

Wet sanding is most useful during fine finishing of cured coatings. Water helps carry away sanding residue and reduce abrasive loading. It should not be used over exposed body filler, unprotected metal, or any primer that the manufacturer does not approve for wet sanding.

Whether sanding wet or dry, clean residue away before applying the next product. Do not allow dirty sanding water to dry across the panel.

Common Automotive Sanding Mistakes

Skipping too many grits

Moving directly from P80 to P320 may leave deep scratches that the finer abrasive cannot remove efficiently. Use a logical progression and do not advance until the previous scratch pattern is gone.

Sanding with fingertips

Fingertips create concentrated pressure that can leave grooves and waves. Use a block wherever the panel shape permits.

Using primer to hide poor bodywork

High-build primer can fill controlled sanding scratches and minor surface texture. It cannot permanently correct low spots, sharp filler edges, or badly shaped repairs.

Sanding through edges

Edges carry less primer and clearcoat than flat panel areas. Reduce pressure, work by hand, and inspect frequently.

Choosing a grit without checking the next product

The correct finishing grit is determined by what will be applied next. Primer, sealer, basecoat, single-stage paint, and clearcoat do not always require the same surface profile.

Failing to clean before sanding

Sanding a dirty panel can spread contamination across the repair. Clean first, sand, remove dust, and complete the paint manufacturer's recommended final cleaning procedure.

Frequently Asked Questions

What grit sandpaper should I use before automotive primer?

P180 to P320 is a common range, depending on the substrate and the primer. High-build primer may accept a coarser scratch than a sealer or direct-to-paint surface. Follow the primer's technical data sheet.

What grit should I use before automotive basecoat?

P400 to P600 is common over primer, while some metallic, pearl, and blend applications call for P600 to P800. The basecoat or sealer technical data sheet should determine the final grit.

Can I apply basecoat over P320 scratches?

Only if the coating manufacturer specifically approves that surface. P320 scratches may show through some colors and paint systems, particularly metallic finishes. Additional refinement or a compatible sealer may be required.

What grit removes orange peel from clearcoat?

Light texture may be corrected with P1500 or P2000. Severe texture may require a more aggressive starting grit, but that increases the risk of removing too much clearcoat. Confirm that the clear is fully cured and has enough film build before sanding.

Do I have to compound after using P3000 or P5000?

Yes. Fine abrasives reduce the severity of the sanding marks, but compounding and polishing are still required to restore full gloss.

Final Sanding Checklist

Before spraying the next coating, confirm that:

-The panel is straight and free of unresolved low spots.

-The previous grit scratches have been completely removed.

-The final grit matches the next product's technical requirements.

-No glossy, unsanded areas remain where adhesion is required.

-Edges and body lines have not been sanded through.

-Dust, residue, grease, wax, and silicone have been removed.

-The panel is completely dry before coating.

There is no single sandpaper grit that works for every stage of automotive refinishing. The best results come from matching the abrasive to the material, progressing through the grits without leaving deep scratches, and following the technical requirements of the paint system.

AutoColorOnline carries automotive sanding discs, sanding blocks, body fillers, primers, paint-finishing abrasives, compounds, polishes, and other supplies needed to take a repair from bare metal to final gloss.