Sanding Grit Progression in 2026: The Honest Sequence for Wood, Metal, and Auto Body

Sanding is where finishing time gets quietly burned. Most projects spend more time sanding than every other step combined, and the schedule slips because either the grit sequence was wrong (causing repeat passes) or the operator went too fine on bare wood (causing finish problems that meant stripping and starting over). The honest sanding sequence is shorter and more deliberate than most beginners try. Here is what actually matters at each grit, and where to stop.

What sandpaper does at the scratch level

A piece of sandpaper is just abrasive grit (aluminum oxide, garnet, ceramic, silicon carbide) bonded to a paper or cloth backing. The grit cuts tiny parallel scratches into the surface as you drag it. Each grit’s scratch depth is roughly half the previous coarser grit. A successful sanding sequence removes the visible scratches from one grit by cutting shallower scratches with the next.

The grit numbering system (CAMI, used in the US) goes:

• 40 to 60: coarse stock removal, raw lumber dressing
• 80 to 100: leveling, removing planer marks
• 120 to 150: smoothing
• 180 to 220: final wood prep before most finishes
• 240 to 320: knocking down raised grain after water-based finish, light scuff between coats
• 400 to 600: between coats of high-build finishes, polishing
• 800 to 2000: final polish, automotive
• 2500 to 5000: rubbing out finish, polishing compound prep

European P-grade numbering is slightly different above 220 (a P320 is closer to a 240 in CAMI), but most US-sold paper uses CAMI even when marked P.

Skip-grit rule

The rule is do not skip more than one full grit step in the sequence. Going from 80 to 120 is fine. Going from 80 to 180 is too far, because the 180 cannot cut deep enough to remove the 80 grit scratches in a reasonable time. You end up sanding for 30 minutes at 180 trying to erase scratches that the 100 or 120 would have cleaned up in 90 seconds.

The standard wood-sanding progression is 80, 120, 150, 180. Four grits. Each step takes about half the time of the previous step because the scratches you are removing are shallower.

Where to start on each material

Planed lumber straight from a thickness planer

Start at 120 grit. The planer left no scratches, only mill marks that are mostly cosmetic. 120 to 150 to 180 covers the whole job in 3 to 5 minutes per square foot with a random-orbit sander.

Rough lumber or boards with deep planer snipe

Start at 80 grit. Work to flat, then 100 (optional, can skip on softer woods) to 120 to 150 to 180.

Reclaimed lumber with old finish

Start at 60 or 80 with a half-sheet sander or random-orbit sander and aluminum oxide paper. Take all the old finish off. Then proceed with the normal 100 to 120 to 150 to 180 sequence on the bare wood.

Hand-cut joinery (paring marks, tenon shoulders)

Start at 150 if the chisel work was clean, 120 if there are visible chisel marks. Go up to 180. Most joinery surfaces hide inside the joint or in shadow lines, so 220 is wasted.

The 180 vs 220 question

The final grit before finish depends on the finish:

• Pure oils and hardwax oils: 150 to 180. Finer leaves the surface too closed for the oil to penetrate well.
• Water-based polyurethane: 180. Then after the first coat (which raises grain), 320 to scuff.
• Oil-based polyurethane: 180 to 220. The slower-curing finish self-levels enough that fine final grits are not necessary.
• Lacquer (sprayed): 180 to 220. Each coat melts into the previous so sanding scratches under the first coat get partially redistributed.
• Shellac (french polished): 220 to 320 for the final wood prep. The padded application reveals the slightest scratch.
• Stain followed by topcoat: 180 only. Going to 220 closes the pores and the stain pulls less, which gives an inconsistent color.

Going to 320, 400, or higher on raw wood for a stained piece is one of the most common reasons stain comes out blotchy. The wood needs open pores to absorb the pigment.

Between coats of film finish

The scuff sand between coats of polyurethane or lacquer needs only enough abrasion to mechanically key the next coat and knock down dust nibs. The grit:

• Polyurethane (oil and water-based): 320 to 400. Light pressure. Wipe the dust off with a damp cloth or tack rag.
• Lacquer: usually no inter-coat sanding needed because each coat melts into the previous. Optionally 400 if dust nibs are bad.
• Shellac: no inter-coat sanding. Each pad goes onto the previous coat that has not fully cured.

Burning through to bare wood between coats is the warning that you used too coarse a grit or too much pressure. Stop, recoat, re-sand at 400.

Final rub-out for a glass-smooth surface

After the last coat of polyurethane or lacquer is fully cured (the manufacturer’s cure time, not the recoat time), the surface can be rubbed out for a satin-to-gloss finish:

1. 600 grit wet-sanding with mineral spirits or water (depending on finish), light pressure.
2. 1500 grit wet-sand.
3. Optional: 2000 grit wet-sand.
4. 0000 steel wool with paste wax for a satin sheen, or buff with a power buffer and rubbing compound for high gloss.

This step is what separates production furniture from custom furniture. Skip it and the finish looks fine; do it and the finish looks like jewelry. Most projects benefit from at least the steel-wool-and-wax step.

Sander selection by stage

The right tool for each grit range:

• Belt sander (60 to 100 grit): for fast stock removal on rough lumber. Aggressive and hard to control. Skip if a thickness planer is available.
• Random-orbit sander (80 to 320 grit): the workhorse for almost all wood finishing. Festool ETS EC 125 (220 dollars), Bosch ROS20VSC (75 dollars), Mirka DEROS (510 dollars premium).
• Quarter-sheet finish sander (180 to 320 grit): good for flat areas where the random-orbit pattern is too aggressive. Less common now.
• Hand sanding block (any grit): final passes with the grain, inside corners, profiles.
• Detail sander (150 to 220): inside corners on cabinets and small parts.

For most home shops, one quality random-orbit sander plus a rubber sanding block covers everything from rough stock to final prep. Add a detail sander only if you do a lot of cabinetry.

Loaded paper and when to change

Sandpaper has a finite useful life. Once the grit is loaded with finish, pitch, or fine dust, it stops cutting and starts polishing, which leaves shiny patches and burnishes the wood. Change discs:

• Whenever the disc starts gliding instead of cutting
• After 5 to 8 minutes of active use on hardwood
• Immediately when the disc loads with finish (no amount of pressure brings it back)

Quality discs (Mirka Abranet, Festool Granat) at 1 to 2 dollars each cut faster and last longer than the 10-for-5-dollars bargain discs. The math favors the better disc. For how we test abrasives across projects, see our methodology page. Sand smart, not long, and the finish coats fall into place.

Frequently asked questions