Guides · 6 min read

Up the grits: sanding from shape to finish

Sixty cuts, five thousand polishes, and the ladder in between. Which grit starts which job, why you never skip more than one rung, and what the dust asks of your face.

You start with rough wood, or an old finish. Your sander is ready. A box of discs sits on the bench, full of numbers. This is the walk from shape to smoothness, the steady climb up through the grits. It is a process of replacement. Each finer grit replaces the pattern of scratches left by the coarser one before it. Skip steps and the old scratches stay, hiding under the new finish. Go too slow and you spend hours on work that does not show. The goal is to know the ladder, match the tool, and protect your lungs while you climb.

What a grit number is

Open a pack of sandpaper and you see numbers: 80, 120, 220. The grit number is a count. It tells you how many abrasive particles are fixed to a standard unit area of the backing material. A lower number means fewer, larger particles spread farther apart. These are coarse grits. They cut fast and deep, leaving pronounced scratches. A higher number means many more, much smaller particles packed tightly together. These are fine grits. They cut slowly and shallowly, leaving a scratch pattern so fine it feels smooth to the touch.

Think of it like choosing a shovel for a job. A 60-grit disc is your spade. It moves material quickly, shaping and leveling. A 220-grit disc is your trowel. It refines the surface, smoothing out the marks the spade left. A 3000-grit sheet is your polishing cloth. It works on the finish itself, not the wood. The numbers are consistent. A 120-grit disc from one maker performs much like a 120-grit from another. The system lets you plan your work from coarse to fine, knowing each step has a defined role.

The LotFancy assortments cover a wide range, from the coarse 60 grit up to the polishing-grade 5000. This gives you the rungs for the full ladder.

The ladder, rung by rung

Every sanding project is a climb. You begin at the bottom, where the coarse grits live, and move upward one rung at a time. The purpose of each step is singular. It must remove the scratches left by the previous grit. Only then do you move to the next finer one.

Start at 60 or 80 grit for heavy shaping. This is for leveling joints, removing old paint or varnish, or taking down significant imperfections in raw wood. The scratches will be deep and obvious. Your goal here is not smoothness, it is flatness and basic shape.

Move to 120 grit. This is the workhorse for initial smoothing. It efficiently removes the deep scratches from the 80-grit stage, replacing them with a finer, more uniform pattern. Most of the material removal happens in these first two steps. The surface will still feel quite rough.

The 180 to 220-grit range is the prep for finish. Here, you erase the 120-grit scratches. The surface becomes smooth to the palm. For many projects, especially those that will receive a stain or an oil finish, stopping at 220 grit is perfectly acceptable. The wood is ready.

Finer grits, from 320 up through 500, are for finish preparation. They create an exceptionally fine surface for clear coats like polyurethane or lacquer. Sanding between coats of finish is also done in this range, often with 320 or 400 grit, to level dust nibs and provide a tooth for the next coat.

Beyond 500, you enter the realm of polishing. Grits of 1000, 2000, 3000, and up are typically used wet, often on automotive clear coats or high-gloss lacquers. They polish out orange peel or finer scratches, preparing the surface for a final buffing compound. For wood, this is rare unless you are working on a piano finish.

Our products give you the rungs. You find 60 through 320 grit in our 5-inch disc assortments for random orbital sanders. For larger 6-inch sanders, we offer 80-grit discs in bulk packs. The climb to a fine polish uses our 9x11 inch or 9x3.6 inch wet-dry sheets, which go all the way to 3000 or 5000 grit.

Never skip more than one rung

The ladder has a rule. You can step over one rung, but never two. Moving from 80 grit to 120 grit is a single skip, and it is often done. The 120-grit abrasive is still coarse enough to engage with and remove the scratches from the 80-grit stage in a reasonable amount of time.

Skipping from 80 grit directly to 220 grit is a different matter. The 220-grit particles are too fine. They will skate over the top of the deep 80-grit scratches, unable to cut down to their bottom. You will sand and sand, seeing a hazy smoothness develop between the scratches, but the deep grooves remain. They will become glaringly visible once a stain or finish is applied, shadowy lines trapped under the surface. You have wasted time and paper.

The physics are simple. Each grit size is designed to cut scratches of a certain depth. The next grit in sequence is sized to cut just deep enough to remove those scratches. Jump too far ahead and the abrasive lacks the teeth for the job. It is like trying to file down a saw cut with a nail buffer.

General woodworking practice is clear. Work up through the sequence so each stage does its job completely. You know you are ready to move on when the entire surface shows a uniform scratch pattern from the current grit, with no traces of the previous, coarser pattern visible. A bright light raked across the surface is the best test. This disciplined approach is ultimately faster than trying to rush. It prevents the heartache of discovering hidden scratches after you have applied your beautiful finish.

Matching the disc to the sander

The sander dictates the disc. Using the wrong one leads to poor performance, extra dust, or a disc that simply will not stay on.

Most modern finishing sanders use a hook-and-loop backing pad. The fuzzy loops are on the sander’s pad. The discs have a backing covered in tiny hooks. Press them together and they grip. This system allows for quick changes and a secure hold. The backing must be the right type. Our discs are all designed for this hook-and-loop system.

Next is the hole pattern. Random orbital and sheet sanders have holes in their pads to channel dust into a built-in collection bag or a vacuum hose. The sanding disc must have matching holes. If the holes do not align, dust clogs under the disc, reducing cutting efficiency and leaving swirl marks on your work. We offer two common patterns. The 5-inch disc with 8 holes fits the vast majority of 5-inch random orbital sanders. The 6-inch disc with 6 holes is for larger 6-inch models. Check your sander’s manual or existing discs to be sure.

For detail work, shape matters. Smaller mouse sanders or detail sanders from brands like Black and Decker and Ryobi often use triangular pads. Our triangle sheets are pre-cut to fit these models exactly, offered in assortments from 60 to 220 grit. There is no trimming or waste.

Finally, consider the job duration. For a big floor refinishing project, you will go through many coarse-grit discs. Our 100-pack of 6-inch, 80-grit discs is made for that. For the walk up through the grits on a single piece of furniture, an assortment pack of 5-inch discs covering 60 to 320 grit provides one of each step you will likely need.

Wet, dry, and what silicon carbide adds

Most sanding is done dry. The abrasive is aluminum oxide or similar, bonded to a heavy paper or cloth backing. It works well on wood and many other materials. But for fine finishing work, especially on hardened surfaces like automotive paint or cured lacquer, you introduce water. This is wet sanding.

Wet sanding serves several purposes. The water acts as a lubricant, reducing friction and heat. It also floats away the sanding residue, preventing the abrasive particles and the material being removed from clogging the sandpaper. This keeps the abrasive cutting cleaner and longer. The result is a finer, more consistent scratch pattern. It is almost exclusively done with the high grits, from about 1000 upward, to polish a surface to a high gloss.

Not all sandpaper can get wet. Standard paper-backed discs will disintegrate. For wet sanding, you need a waterproof backing and an abrasive that will not rust or break down in water. Silicon carbide is that abrasive. It is exceptionally hard and sharp. Our wet-dry sheets use silicon carbide bonded to a special waterproof backing. They are marked for use wet or dry.

The sheets come in two useful sizes. The 9x11 inch sheet is standard. You can tear it into smaller pieces as needed. The 9x3.6 inch strip is a clever format. It is the perfect width to wrap around a standard sanding block for wet-sanding larger flat panels, or to use by hand for curved surfaces. These sheets let you climb the highest grits, from 60 or 80 all the way to 3000 or 5000, for that final polish.

What the dust asks of your face

Sanding creates dust. Coarse grits make chips and visible powder. Fine grits make a haze that hangs in the air. Wood dust, finish dust, and the dust from composite materials are not just dirt. They are a respiratory hazard. Your lungs are not designed to filter this fine particulate. The protection you choose is not a suggestion. It is a requirement for your long-term health.

The federal guidance from NIOSH, the National Institute for Occupational Safety and Health, sets the standard for respirators. An N95 respirator is the minimum for sanding dust. Its name means it filters out at least 95 percent of airborne particles. But it only works if it seals to your face.

This is the critical detail often missed. The respirator must seal. Every breath you take must pass through the filter material, not around the edges. If air leaks in through the gaps, you are breathing unfiltered dust. Several factors break the seal. Facial hair, even a day’s stubble, can create a gap. The arms of eyeglasses can disrupt the seal along the nose bridge. Wearing jewelry like stud earrings can interfere with the fit.

Putting it on correctly matters. The straps should not be crossed. They go over the crown of your head and around the neck. The metal nose clip must be pinched and molded snugly to the bridge of your nose. Once on, you should perform a seal check. Cover the respirator with your hands and exhale gently. Feel for any air leaking out around the edges, especially at the nose. If you feel leakage, readjust the nose clip and straps until the seal is secure.

A respirator is a maintenance item. It is not worn if it is damaged, visibly dirty, or becomes damp from breath or humidity. The moisture degrades the filter’s effectiveness and can promote microbial growth. Our catalog includes NIOSH-approved N95 respirators. Some models have an exhalation valve, which makes breathing out easier and reduces heat buildup inside the mask. They are sold in practical packs of 10 or 20, acknowledging that they are disposable and need regular replacement.

That is the whole walk. You choose the grit for the task at hand, match the disc to the sander’s pattern, and decide when a sheet works dry or goes under water for the final polish. Through every step you protect your face, because the dust is part of the work and managing it is part of the craft. With the grits laid out in order and the right disc on the pad, the path from shape to finish is a straight, unhurried climb.