Feather-Edge Chipped Car Paint: 80–400 Grit Primer-Ready

Chipped paint around door edges, hoods, and rockers is more than a cosmetic issue—left untreated, it invites rust and keeps new paint from laying flat. The professional fix is feather edging: sanding the damaged spot so the paint layers taper smoothly into the surrounding finish, leaving no hard “ledge” that will telegraph through primer and topcoat. In this guide, you’ll learn a safe, repeatable grit sequence (80→400) and a step-by-step method to go from jagged chip to primer-ready surface without enlarging the repair.

Why Sanding (Feather Edging) Matters

A paint chip isn’t just missing color; it’s a tiny crater with stacked layers—clear, base, primer—ending abruptly next to bare metal or plastic. If you spray primer over that cliff, you’ll still see the edge. Feather edging removes only enough material to create a smooth ramp, improving adhesion and making the repair invisible after paint. The right grits and light pressure prevent heat, gouges, and over-sanding the thin clear coat along body lines.

Tools & Safety

• Wet/dry silicon carbide sandpaper sheets (80–400, plus optional 600 for ultra-smooth primer surfacing).
• Small rigid sanding block (1×2 in. or similar) and a soft foam pad for gentle contours.
• Masking tape, masking paper/plastic, and trim-safe edge guards.
• Wax & grease remover, isopropyl alcohol, microfiber towels, and tack cloth.
• Filler/putty for deeper divots (if needed), primer-surfacer, and matching touch-up/base + clear.
• PPE: nitrile gloves, eye protection, and a quality respirator—dust and solvents are no joke.

Recommended Grit Sequence

• 80–100 grit: Initial edge knock-down and removal of loose/undercut paint.
• 180–240 grit: Transition zone—erase coarse scratches while widening the feather.
• 320–400 grit: Pre-primer refinement for a tight, uniform scratch field.
• Optional 600 grit: Light surfacing after primer for ultra-smooth topcoat.

Step-by-Step: Feather-Edge a Chip to Primer-Ready

1. Clean and assess. Wash the area and wipe with wax & grease remover so abrasives cut cleanly. Use a fingernail to feel the chip’s edge—this tells you how much taper you’ll need.
2. Protect surroundings. Mask trim and tape a small window around the defect so you don’t haze good clear coat. Keep tape a bit away from your sanding zone so you can blend outward.
3. Start the taper (coarse cut). For small chips or thin edges, begin with 100 Grit (25-pack) on a small, hard block. Sand short, light strokes across the chip edge to lower the paint ridge without digging a dish. Reserve 80 grit for ragged, thick edges only; use sparingly to avoid deep tracks.
4. Widen and smooth the transition. Switch to 240 Grit (50-pack) and sand a slightly larger circle, blending the ridge outward. Your goal is to replace the coarse scratches fully and create a gentle ramp you can’t catch with a fingernail.
5. Refine to primer-ready. Finish the raw feather with 400 Grit (100-pack) on a soft pad to unify the scratch pattern. This leaves enough tooth for primer while keeping the repair invisible under topcoat.
6. Fill, if necessary. If the chip crater is deep, apply a thin glazing putty. After it cures, block-sand the spot 240 → 400 until the putty is perfectly flush and the feather still disappears to the touch.
7. Degrease and prime. Wipe the area with alcohol, tack, then apply light coats of primer-surfacer, staying just beyond the feathered zone. Allow proper flash/dry per product label.
8. Surface the primer. Once fully dry, sand primer with 600 (light touch, soft pad) to remove any texture. Re-spot prime if you cut through and repeat a brief 400 → 600 surfacing.
9. Blend and paint. For color, extend base slightly beyond the primer edge; then extend clear beyond the base. Maintain wet edges and follow blending guidelines for your paint system.
10. Final inspect. Under raking light, there should be no visible ridge or halo. If you see a ring, you didn’t fully remove a coarse scratch—back up one grit locally and re-blend.

Special Cases

Plastic bumpers (PP/EPDM): Don’t over-sand—plastic heats and smears. Keep pressure low, and use an adhesion promoter after feathering before primer.
Edges and body lines: Clear is thinnest here. Mask the hard edge during coarse steps, then remove tape for the finer passes so you don’t burn through.
Bare metal spots: If tiny, your primer-surfacer may suffice; for larger exposures, spot a corrosion-resistant primer first, then build with surfacer.
Metallic/pearl colors: The feather must be flawless—coarse scratches telegraph under flake. Spend extra time at 400 and keep your blend zone generous.

Pro Tips

• Use a small, hard block to keep the surface flat; fingers alone create dishes.
• Sand across the edge to lower the ridge, then finish with light, circular or with-panel strokes at finer grits.
• Replace paper early—dull sheets polish, then gouge. Fresh grit = cooler, cleaner cut.
• Let the paper cut; don’t lean. Pressure creates heat and smears surrounding clear.
• Feather in expanding rings as you refine grits so the transition is invisible to both touch and sight.
• Keep the area clean between grits—rogue particles make random scratches you’ll chase later.

Aftercare

• Allow primer and clear to cure fully per product specs before washing or waxing.
• For small spot repairs, a gentle compound and polish after cure will level minor texture without thinning the new film excessively.
• Seal rockers/edges with protective film or mud flaps if chips are recurring due to driving conditions.

FAQs

• Can I skip to 320/400? Only if the chip edge is already low and smooth. Most chips need a brief 100–180 step or the ridge will print through.
• Dry or wet sanding? Dry gives clearer visual feedback during feathering; you can wet-sand primer at 600 for final surfacing.
• Do I always need filler? No. If the crater is shallow, careful feathering plus primer-surfacer is enough.
• DA sander or hand block? A DA can work at fine grits, but a small hand block is safer and flatter for the coarse and mid steps.
• Why does a ring reappear after paint? Usually a coarse scratch or a hard edge remained. Back up one grit, expand the feather, and re-prime.

Watch & Learn

Bottom line: Keep your pressure light, your block small and flat, and your grits disciplined: 100 → 240 → 400 (then prime and surface at 600). With the right sheets—100 Grit (25-pack) to start the taper, 240 Grit (50-pack) to widen and smooth, and 400 Grit (100-pack) to finish—you’ll be primer-ready with a feathered transition that disappears after paint.