The nail file is the workhorse of the nail technician’s kit just as jeans are the workhorse of the average person’s wardrobe. And while both started out with just one basic style (the garnet and wood emery board invented by Joe Lupo in 1920 is your basic “Levi’s jeans” of nail files), each is now available in a plethora of styles and materials to suit every occasion. One file manufacturer alone makes 380 different nail files, and another mentions 40 different shapes.

While the basic construction of an abrasive adhered to a backing and attached to a core has changed little since the wood emery board was invented, changes have come in the materials and styles all designed to benefit the nail technician.

Wardrobe Basics

A file’s grit value is determined by the grains of abrasive in a one-inch square, explains Bobbi Berman of B&W Files in Dania-Hollywood, Fla. The lower the grit value, the coarser the file. “Envision a one-inch square filled with 100 grains of sand; it will be very rough,” she explains. “If you take a one-inch square and fill it with 240 grains of sand it will be much smoother.

According to file manufacturers, the best-selling nail file today is a combination 100/180 silicon carbide file. And with good reason - the 100-grit side is ideal for shaping an acrylic nail and reducing the length, while the 180 grit smoothes and shapes the surface. And if you guessed the second- best seller is the 3-way buffing block, you’re right: The buffing block is ideal for finishing both artificial and natural nails. And manufacturers report the original garnet and wood file remains a strong seller, because at 15-29$ it remains the least expensive file. A silicon carbide file starts at about 50¢ and goes up from there.

Any nail technician can do the full range of nail services with just four basic nail files: a coarse file (around 100 grit) for shaping acrylic and taking the length or surface down quickly; a medium file (180-220 grit) for smoothing artificial nails and shaping artificial and natural nails; a fine file (400-600 grit) for finishing artificial and natural nails; and a buffer, or microabrasive, (900- 12,000 grit) to buff and shine the nail surface.

Garnet vs. aluminum oxide vs. silicon carbide vs. zebra; cushioned vs. un-cushioned, sanitizable vs. washable vs. non-washable; board vs. block, tapered vs. rectangular, fat vs. thin - all of these choices are a matter of personal preference. “Most of the materials used in files have been used for a long time,” says Travis Bills, owner of The File Factory (Irvine, Calif.). “The changes are in the range of different materials, colors, and shapes.”

Don’t forget to consider the client when choosing your files. That’s where fun and colorful comes in. Worldwide Cosmetics’ (N. Hollywood, Calif.) Fantasy Files come in 28 different patterns, and are made specifically to encourage retail sales. “The files are so unusual that when someone pulls one out of her purse or drawer, people ask where she got it,” says Stuart Schwartz, sales manager for Worldwide. “When nail technicians put a display on their table, the files fly off.”

Can’t Get Clean Enough

Different shapes and colors account for many of the “new” file styles available to nail technicians. However, over the past 15 years there have been genuine innovations in materials and manufacturing methods.

While Mylar-backed files have been around since the ‘80s, because of their cost (the average Mylar-backed file costs 80¢ to $1.30) the durable, long-lasting backing didn’t gain favour with nail technicians until they were marketed as sanitizable. With the increasing attention to sanitation, sanitizable files, which can be safely washed and soaked in sanitizing solution indefinitely, quickly found a niche. Many manufacturers have introduced sanitizable files since Flowery Beauty Products (Greenwich, Conn.) entered the market in 1992 with Mylar- backed Purifiles. In 1996 Backscratchers Salon Systems addressed the cost complaint by introducing Septifiles. Each file has a plastic handle that is sanitizable and comes with adhesive-backed disposable grit strips. The strips are disposed of after each use, keeping costs down for nail technicians and accommodating state board regulations in California, Iowa, New York, and New Jersey, which prohibit reusing files on clients regardless of whether they are sanitizable.

Schwartz argues that Mylar files may cost less in the long run. “When you think about how many times you can use a Mylar file compared to one that isn’t made of Mylar, you’re really spending less money” he says.

In early June, Rudolph International, (Brea, Calif.) announced the biggest file innovation in several years: antibacterial files. “These files are treated with microencapsulated germicides and fungicides,” explains Jim Rudolph, president. Initially we’re offering them in all shapes of files and foot boards in 80-, 100-, and 180-grit files.

And we may do it on 3-way buffers because they are used over and over.”

Micro-encapsulation is not a new technology—it’s how perfume manufacturers make the “scratch and sniff” cards inserted into magazines. But it’s taken a long time to successfully adapt that technology to applying micro-encapsulated germicides to nail files.

“Look at an abrasive under a microscope and you see peaks and valleys,” Rudolph says. “The little capsules go down into the valleys and crevices and remain there until they are ruptured. They only activate when they are ruptured so as the file wears down and you go deeper into the crevices, you’ll always keep reaching new capsules.”

The company is currently testing the technology to see if it kills all bacteria for the life of the file. Happily, the new technology won’t cost users much. “At retail they’ll run about 8<t more, so if a nail technician was paying 60$ for a standard file shell pay about 68<t for an antibacterial file,” Rudolph says.

Fat Is Beautiful

For nail technicians who love the thick cushion of a buffer but want the length of a standard board, H8cH introduced Nail Friend. While cushioned boards have been around since the late ‘70s, Nail Friend measures in at a hefty half-inch-thick. “We use special layers of foam that go from very hard to soft. The advantage to this is that it goes around the contour of the nail. We received a patent on it because we proved that when a file is constructed with a specific flexibility it speeds filing up to 12 times. This is especially important in buffing,” explains Houshang Rastegar, president of H&H Products (Westlake Village, Calif.)

Another new type of thick board has the abrasive sprayed directly onto the foam, rather than onto a backing that is then attached to the foam. Both Rudolph International and DHS, among others, have these so-called sponge files. “What we’ve done is taken the advantages of a foam block and how it contours to the nail and adapted it for the people who prefer [the shape of] standard files,” explains Todd Hess of DHS (Ventura, Calif.). “There are no paper edges to cut the cuticles.” Sponge files also are sanitizable.

The technology used for sponge files, called The Turtle File by Rudolph International and Sponge Board by DHS, is the same one used to create a white buffing block. Because the abrasive is sprayed directly onto the foam backing, the grit tends to settle into the cells of the foam, making them less aggressive on the nail surface, explains Rudolph. This type of file is best used for smoothing and finishing nails rather than for heavy shaping.

“We don’t suggest technicians try and shape a nail with a Sponge Board like they would with a 100-grit [standard] file,” says Hess. “When you’ve got a nail file where the grit is adhered to a stiff backing, the backing prevents the file from breaking apart. If you were to try to do the same thing with the Sponge Board you might end up with some tears in the board.”

Talk About Long- Wearing

While not a new technology, the filing stone is gaining new popularity recently. The Ruby Stone, for example, has been around for about 20 years and is actually made of aluminum oxide, a commonly used abrasive on nail files (most white and colored files, in fact, are made of aluminum oxide, which is naturally white and is the only abrasive that can be dyed).

The Ruby Stone is recommended for use on natural nails and comes in a 180-grit for hard natural nails and a 220-grit for soft natural nails.

“The [aluminum oxide] crystals are bonded together with porcelain. Imagine looking through a microscope and seeing thousands of diamond-shaped crystals; where their points meet there’s a microscopic gob of porcelain holding the crystals together,” explains Larry Hudson, president of ESI Industries (Grand Rapids, Mich.). While most abrasives are electrostatically charged to make the crystals stand up on edge, in the Ruby Stone they are bonded randomly, resulting in less dramatic peaks and valleys.

Quality Pays for Itself

For a nail technician standing in front of a wall of 100 different files, it’s easy to let the purchasing decision be swayed by price. But less expensive files can cost more in the long run. Cheaply made files can shed grit and wear out quickly, buckle and crease, become too flexible (requiring more pressure and time for the same results), and cut cuticles if they’re cut unevenly.

There are several tests you can use to gauge quality while shopping for files. “On wood files, look at the pliability” advises Geoff Geils, president of Flowery Beauty Products. “See if it’s rigid and how fast it springs back to its original shape. You don’t want it to be flimsy because it will require you to apply more pressure when you’re filing. And look at the lamination of the paper: There should be no splits or frayed edges. Then look at the paper for a richer-looking abrasive and a uniformity of grit. Cheaper files will have less grit.”

For silicon carbide files, “also check the rigidity and the die cut,” Geils continues. “Then look at the side of the file; the paper should be black or dark gray. That’s the oil resin coating on the inside and means the abrasive will last a lot longer.

“On cushioned boards, look at the cushion — you want a closed-cell foam so it should be dense. When you push on the surface of the file it should pop right back out. You should never have direct contact with the core. With cheaper cushioned boards you can feel the core. The other thing you want is a rigid file; some manufacturers cut back on costs by using a less- dense core. If it flexes too much, the paper will crack and break. A nice stiff file will require less pressure to file, have fewer creases, and less ‘popping,’ (when the paper pops off the core).” Also look for a clean die cut; you don’t want a serrated edge or the cuticle will catch on the burrs.”

With all the file choices available today, it makes sense to experiment with a” variety of styles and shapes in search of a file that increases your comfort and decreases your filing time. Considering that even the most pricey files are usually less than $2.50 per board, the file is one implement you can afford to shop around for— as long as you don’t compromise on quality.

What Is a File Made Of?

Use this guide to understand the materials most commonly used in file abrasives, backings, and substrates (cores). Each component has its own strengths and weaknesses; it’s up to you to decide which ones make a file best suited for your needs.


Silicon Carbide. A bluish-black synthetic crystalline compound; one of the hardest known substances; individual crystals have very jagged edges with high peaks and valleys; cuts deeper, faster; tends to shed black dust on the nails during use.

Aluminum Oxide. A chemical compound widely found in nature; only abrasive that can be dyed; individual crystals have less dramatic peaks and valleys than silicon carbide; with the same grit and pressure, it is less likely to “shred” product or natural nails.

Garnet. Unground, it is a gemstone; reddish-brown in color; most commonly used on wood files; a long-lasting, inexpensive abrasive; the jaggedness of the individual crystals fell between silicone carbide and aluminum oxide.

Silicon Carbide With Zinc Sterate Coating (“zebra”). The zinc sterate coating is a lubricant that prevents the grit from “loading up” with filing dust; grit feels smoother than the same grit of other abrasives.

Compressed Aluminum Oxide. Compressed and bonded with porcelain, it results in a “filing stone”;comes in 180 and 220 grits only, best used for shaping and smoothing natural nails; doesn’t absorb water or chemicals; can be used like a pumice stone to remove excess cuticle and hangnails; should never wear out.


Paper. The first abrasive backing used on the original wood garnet files; inexpensive durable; not water-resistant

Waterproof Paper. Paper impregnated with an oil resin; dark gray or black in color; can be immersed indefinitely in water and temporarily in sanitizing solutions.

Mylar. Trade name for polyester film; washable; sanitizable; very durable and long-lasting: more expensive than files with paper backings.

Cloth. Cotton is most commonly used; the most flexible of all abrasive backings; higher-cost backing, very long-lasting; won’t crease; abrasives tend to embed in the cloth, resulting in less aggressive cutting action; commonly found on buffers.


Wood. First substrate used to make files; still very popular; inexpensive; rigid; most com­monly used with garnet abrasive.

Plastic. High-impact polystyrene is most commonly used; more flexible than wood; commonly overlaid with polyethylene foam in cushioned files; without a polyethylene foam overlay the plastic tends to transmit more vibration to technician’s hand than a wood substrate; look for a plastic core that is neither so rigid it won’t give or so flexible it bends easily when pressed on the nail surface.

Foam. Polyethylene is most commonly used foam; used in buffing blocks and cushioned files; dense, closed-cell foam is waterproof and firm (open-cell foam absorbs water and is more spongy); allows file to contour to nail, allowing filing action on more than one contact point, requires more pressure for filing; on some files the abrasive is embedded in foam without a backing.

Guide to Grits

This chart was prepared with the assistance of DHS, ESI Industries, H&H, Flowery Beauty Products and Tropical Shine/Realys.


60-80   Extra Coarse Reducing the length of extra long nails or shaping very thick or misshapen acrylics or gels; also used for scoring the edges of other files.
100-150         Coarse          Reducing the length of and shaping acrylics or gels
150-240 Medium Shaping the free edge of acrylics or gels; light shaping of acrylics or gels; sometimes used to lightly etch the natural nail in preparation for product (many manufacturers recommend against etching the nail surface with any file); grits higher than 220 are good for shaping and smoothing all nail surfaces as well as the free edges of natural nails.
240-400 Fine Finishing work on acrylics, wraps, and gels; filing on natural nails.
400-900 Extra Fine Finishing natural nails; removing ridges and stains from natural nails; preparing all nail surfaces for buffing and shining.
900-12,000 Buffers (Microabrasives) Smoothing and shining both artificial and natural nails.


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