Sanding With Grinder (Angle Grinder as Sander). Sandpaper grinder

WHICH SANDING DISC IS BEST?

When considering what is the best sanding disc to use for a specific job there is an overwhelming range of different discs, grains and grits available on the market. It is difficult to know what to choose for your job. This article will address the most suitable disc to use depending on your requirements.

Different Sandpaper Grains

Not only does the density of sandpaper grit make a difference in the success of your sanding project, but the type of abrasive material does, too. The following is a brief description of the more common types of abrasive grains used in sandpaper products.

Aluminium oxide (generally brown in colour), is a durable synthetic grit, is well suited for sanding and polishing various types of metal, including bronze and alloy steel, in addition to being a good choice for sanding all types of woods. Unfortunately this grain is not suitable for work on stainless steel as it is not INOX (iron free) grade. For this reason Smith ARROW do not sell sanding discs in this grain.

Zirconium / Zirconia (generally blue/green in colour) is suitable for use on all materials including wood, fiberglass, metal, brass, aluminium, and stainless steel – including painted surfaces. Unlike aluminium oxide zirconia can be used on both mild and stainless steel, and will cut faster and last four to five times longer than aluminium oxide discs. This grain is long-lasting and well-suited for grinding away burrs on metal and for an initial sanding of rough wood. When sanding metal with zirconia alumina, the grit particles can actually become sharper, so you won’t have to change sandpaper frequently. Smith ARROW stock fibre discs and flap discs in this grain type.

Ceramic abrasive grain (generally red in colour) is the top of the range in terms of both effective cutting ability and how long the discs will last. It is extremely tough, sharp, and long-wearing and does not dull quickly because of its extreme density, making it best for aggressive material removal with both wood and all types of metal including Stainless Steel. This makes ceramic discs the best choice for removing stock, and sanding all surfaces in wood or metal. For this reason, ceramic abrasive discs are generally more popular in the more coarse grits. Ceramic abrasives are durable, and lasting longer than both aluminium oxide and zirconia.

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Different Sanding Abrasive Discs for Angle Grinders

Manufactured from an abrasive fibre sandpaper, Fibre Discs are a round disc with a round hole or star pattern in the centre. They are made from a stiff, card–like backing coated in a wide variety of abrasive materials and are generally used with a rubber or polyurethane backing pad on an angle grinder. They are the recommended abrasive wheels for medium to light stock removal on both mild and stainless steel. Used on a backing plate on an angle grinder, resin fibre discs have an extensive scope of applications ranging from fine and coarse sanding, blending welds, deburring and de-rusting. The most common use of fibre sanding discs is for sanding layers of paint, sanding back welds and welding splatter or generally taking work back to bare metal.

Flap discs are a very popular sanding / grinding product due to their versatility and long lasting design attributes. Applied directly to the angle grinder with no need for a sanding pad, frap discs are cleverly designed for Rapid effective removal of stock in most applications. Their design allows for the cutting edge of each flap to fall away cleanly once the abrasive grain has been used up, exposing the fresh face of the new abrasive grain on the flap underneath it. Essentially, flap discs are designed to allow for the abrasive grain to cut effectively for as long as possible and then release cleanly to open up the fresh cutting grain on the flap underneath – providing a more consistent finish and uniform cut rate. Flap discs are one of the best abrasive /grinding wheel for fast stock removal, deburring welds and provide grinding, blending and finishing with one product.

The main application for using a “ poly strip disc ” or “strip disc” is when it is important for the substrate or underlying material is to be left virtually untouched. All other removal tools such as sanding discs, grinding discs and flap discs will remove the wood or steel underneath, for example paint once it has been removed, and damage that surface. The value of using a strip disc in this situation is that it will remove the rust or the paint from the surface without starting to remove the steel, or fiberglass or wood that is underneath. Very popular for use in the auto industry, poly strip discs will remove the paint from car panels in just one pass of the grinder without damaging the metal panel underneath and causing “flat spots”.

Different Sanding Grit Sizes

Sandpaper is measured by its grit size, or number of sharp particles per square inch of sandpaper – the lower the grit number, the courser or harsher the grit. A 24 grit sanding product will be very aggressive in the removal of stock leaving harsh scratches on the surface, as opposed to a 600 grit sandpaper which is designed to remove less matrterial in a way that leaves a smoother finish. You need to choose the grit size of sandpaper depending on the particular job you are trying to accomplish. The higher the number, the smaller the grains and the finer the sandpaper grit. Conversely, lower numbers indicate larger grains and overall coarser sandpaper. Many jobs require you to “go through the grits.” This means you start the project using lower numbered grit and use finer pieces of sandpaper as you progress. Each time you advance to a higher grit sandpaper, you remove the scratches from the previous layer. Grit are used as follows:

  • 24 grit: Rough stock removal. It is used for grinding back steel or welds as well as removing paint and varnish that you think might never come off.
  • 36/40 grit: Aggressive grinding and weld removal (very popular), such as sanding the edge of a sticking door to make it close flush.
  • 60 grit: When medium grinding and finishing are required in one step. This grit is a good starting point for most projects involving working with steel or wood.
  • 80 grit: Very similar to the 60 grit, 80 grit is just a little less course and a very popular grit for most metalworking jobs.
  • 120 grit: A good choice for fine surface blending and finishing in both metal and wood working applications.
  • 240 – 400 grit: Extra-fine grit sandpaper is used for light sanding between coats of finish and to sand metal and other hard surfaces
  • 600 grit and higher: Super-fine surface finishing / polishing. Ideal to sand the final layer of finish on wood or metal. It is just strong enough to thin patches and small inconsistencies in the layer’s application, but not rough enough to actually remove anything that would want to be kept.

Smith ARROW stock sanding discs for angle grinders in 24, 36, 40, 60, 80 and 120 grit. If you are seeking an angle grinder sanding disc, Smith ARROW sells:

  • Fibre discs in ceramic and zirconia options. These discs come in 4”. 4.5”. 5” and 7” sizes
  • Flap discs in zirconia, sold in 4”. 4.5”. 5” and 7” sizes
  • Strip discs sold in 4”. 4.5”. 5” and 7”

Sanding With Grinder (Angle Grinder as Sander)

Preparing wood for your next project often requires taking away mill marks or sanding the surface to smooth out any rough edges. And while the angle grinder may not be the first tool you think of for sanding wood, it is a versatile device that can do many things in your workshop.

Can I Use an Angle Grinder for Sanding?

Yes, you can use an angle grinder for sanding. By attaching an abrasive flap disc you can turn the angle grinder into a sander and use it for sanding wood, metal, welded joints etc. The drawback is that, you cannot use it to flatten an uneven surface like a belt sander. While it is not a method to produce accurate results, it works well to remove material fast.

There are two methods you can apply to use your angle grinder to sand.

The first and the most common method is by using the flap disc. The second method is to utilize an orbital sander attachment. While the second option is more complex and require more investment, it offers best results in terms of surface quality.

Let’s start with the first method. While this technique is commonly used in metalworking, it can also be used for sanding wood. Of course, you will need the right type of disc when using the angle grinder for snading. This is where the flap disc comes in. This is a common sanding pad used for the angle grinder which makes removing the top layer of materials much easier to accomplish.

Sanding with Angle Grinder

Keep in mind that you can use the angle grinder for sanding a wide variety of materials from wood and wooden floors to decking, metal, concrete, fiberglass, and more. Another popular use of the angle grinder is to strip away the paint from surfaces such as wood and metal.

Method #1: Use a Flap Disc

The flap disc is a sanding disc that consists of overlapping sections or flaps that are spaced across the surface of the disc. When used on an angle grinder, the flaps can quickly sand large areas in a relatively short time. They are exceptionally well-suited for pallet or reclaimed wood as they can quickly smooth away the surface area.

Type of Flap Disc

You may have noticed there are two basic types of flap discs, flat and angled. The flat version is designed to sand at angles up to 15 degrees. As the name suggests, it is flat across the entire surface area. This is often called a Type 27 flap disc.

The Type 29 flap disc is flat in the center, but then angles downward towards the edges. This flap disc is perfect for sanding at 15 to 25-degree angles. The angle of the disc allows you to sand steeper areas easier and with more consistency compared to a Type 27.

Disc Size

There two sizes to consider; one is the grit size of the abrasive and second is the actual size (diameter) of the disc. To use the flap disc, you will need to find one that is the right size for the job you want to accomplish without being too big or small to be attached to the angle grinder.

Grit Size:

A smaller grit size denotes course grain which removes material at a higher rate, but with a rough finish. For instance, a 30 – 40 grit wheel can be as effective as grinding. For wood, I recommend you start with a 60 or 80 grit wheel and work your way up to 120-grade disc for smoother finish. Be sure to purchase a flap disc that is best suited for your needs.

Step-1: Attach the Flap Disc

Now that you have the right flap disc for the job, attach it securely to the angle grinder. The flap disc operates essentially in the same manner as the grinding discs.

Step-2: Wear Safety Equipment

Be sure to take the proper safety precautions which includes wearing eye protection and ear protection. You may also want to use a pair of safety glove.

Step-3: Match the Angles

Switch on the grinder and gently apply the flap disc to match the angle of the flap disc to the surface. The grinding angle of Type-27 flap disc is approximately 5° to 15° whereas the Type-29 disc requires you to work at angle ranging from 15° to 35° on a relatively flat surface.

Step-4: Let the Disc Do the Work

Do not apply too much pressure on the workpiece. When working with metal, excessive pressure on the flap disc will result in tearing of the flaps. In woodworking this may cause gouging and burn marks which will be very difficult remove.

So, put light pressure and let the disc do the sanding. Then using back and forth motions sand off the top layer of the workpiece.

Step-5: Finish Sanding

Once you have removed the surplus material with the rough disc, switch to a higher grit flap disc to finish your work.

Method #2: Orbit Sander Attachment for Angle Grinder

For top-down sanding, an orbital sander is the preferred device to use. However, you can turn your angle grinder into an orbital sander with the proper attachment. This is an attachment that extends the working distance of the device, so you can create internal curves, profiles, and shells. While the attachment itself is rather small compared to a standard-size orbital sander, it does allow you to do most of the work for far less expense. The attachment is essentially an arm-extension of the angle grinder. It extends the sanding pad outward by enough distance so you can use it at any angle. This overcomes one of the issues with using an angle grinder in which the device itself gets in the way of making certain types of sanding possible. By extending the sanding pad away from the grinder, you put enough distance away from the device to make any type of sanding motion you want.

You can choose an orbit sander attachment that contains a flexible backing pad. This creates a smooth finish to your work. If your goal is to sand without scarring, blemishing, or scratching the wood, then this is the attachment to use.

The downside is that the device is still angled compared to the sanding pad. As a result, you have less control over the sanding action. This also means, you cannot press your weight into the pad as you would with a traditional orbital sander. Plus, the pad itself is relatively small, so it is best used on materials that are also small or have tight corners that would be tricky for a larger sanding pad to reach.

Pros Cons of Using Angle Grinder as a Sander

There are several advantages to using an angle grinder for your sanding needs.

Pros

The first and foremost is the design of the angle grinder itself which allows for quick sanding of surfaces. The open design allows you to work the flap discs at any angle, so you can quickly sand surfaces.

Another strong advantage is that flap discs are relatively inexpensive and will last for a considerable amount of time under normal use conditions. The design of the flap disc combined with its inherent strength means that you can use a single disc for a considerable time before having to change it out.

Changing out flap discs is another advantage of the angle grinder. Its easy access allows you to quickly remove and attach new discs securely in place. This means that you can increase your work productivity by spending less time attaching and detaching discs.

Cons

Of course, the angle grinder does have some limitations compared to traditional sanders. The most obvious is the inability to work on uneven surface to make it flat. You could use the angle grinder to sand the high points and to remove lot of material quickly. But if you are trying to achieve a smooth flat surface, get a real sander.

Another disadvantage is the relatively small size of the discs available. This limits the angle grinder to small and moderate-size pieces of wood for sanding purposes. If you are sanding larger surfaces, such as plywood or large planks, then a belt sander or a random orbital sander is a better tool for the job.

Finally, the design of the angle grinder itself makes it more likely to suffer damages or abrasions because of the lack of control as compared to orbital sanders and other devices.

Get to know how different grit types and grade impact the sanding process so that you always choose the right supplies for the project at hand.

By Bob Vila | Updated Oct 30, 2019 6:39 PM

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If you’ve ever worked with wood, you’re likely familiar with instructions to sand all edges after cutting: before applying a finish, between coats of paint, and so on. Seeing sandpaper on a tools and materials list may seem easy enough to check off—until you hit the hardware store and face stacks of sheets and booklets, each distinctly identified with a different set of numbers, or sandpaper grits. Which did this project call for again?

Different sandpaper grits perform very different jobs, and selecting the right grit can be confusing when you’re starting out. Warm up with these basic recommendations and rules of thumb. This guide will run you through:

  • Selecting the right size of sandpaper grit,
  • Choosing the appropriate coarseness for the project,
  • Considering the best type of grit to choose, and
  • Finding the right tool for the easiest effort.

After you have a few completed projects under your belt, you’ll be an old pro at picking just the right sandpaper.

sanding, grinder, angle, sander, sandpaper

Sizing Sandpaper Grit

Sandpaper isn’t made of sand, of course, but rather it consists of fine particles from either natural or synthetic sources. The particles (also known as grains or grit) are sifted through screens and sorted by size before being bonded with adhesive to a paper, sponge, or cloth-type backing to create an abrasive material that’s handy in a number of do-it-yourself situations.

Distinguishing sandpaper grit sizes is important because not every project requires the same.

In the United States, grit is determined based on a gradation scale established by the Coated Abrasive Manufacturers Institute (CAMI). When shopping for sandpaper, you’ll see numbers such as 80-grit, 100-grit, or 200-grit. Keep in mind:

  • The higher the number, the smaller the grains and the finer the sandpaper grit.
  • And, conversely, lower numbers indicate larger grains and overall coarser sandpaper.

On the CAMI scale, sandpaper grit is measured in microns, and to get an idea of how small a micron is, check out a piece of 100-grit sandpaper. The small grains on the sandpaper measure approximately 141 microns in size, which is equivalent to.00550 of an inch. Very small.

Most sandpaper you buy at DIY centers and lumberyards will bear the CAMI scale, but if you order sandpaper online, you may run across sandpaper grit sized by the Federation of European Producers of Abrasives (FEPA). Grit sized with the FEPA scale is indicated by the letter “P” preceding the grit number. While there are too many grit gradations to list, if you’re buying FEPA-sized sandpaper, the following commonly used CAMI sizes will give you an idea of the corresponding FEPA sizes. FEPA sizes are not an identical match to CAMI sizes, but you can get something very close by selecting one of the two closest FEPA numbers.

  • 40-grit (CAMI) sandpaper corresponds closely to (FEPA) P-36 or P-40
  • 80-grit (CAMI) sandpaper corresponds closely to (FEPA) P-80 or F-100
  • 100-grit (CAMI) sandpaper corresponds closely to (FEPA) P-100 or P-120
  • 120-grit (CAMI) sandpaper corresponds closely to (FEPA) P-120 or P-150
  • 220-grit (CAMI) sandpaper corresponds closely to (FEPA) P-180 or P-220
  • 400-grit (CAMI) sandpaper corresponds closely to (FEPA) P-600 or P-800

Selecting the Correct Coarseness

To make choosing sandpaper easier, manufacturers identify a coarseness level in words on the package in addition to the specific grade. This is essentially a range of grit sizes that are similarly effective for the same sanding work. In fact, it’s not uncommon for projects to call for a certain coarseness level as opposed to a specific grit of sandpaper, so it’s Smart to know what each level includes.

  • Extra coarse sandpaper in the 24- to 36-grit range is tough stuff. It’s used for removing paint and varnish that you think might never come off. The sanding of old floors may also require the abrasiveness of extra coarse sandpaper. Don’t even think about using this stuff on any but the toughest jobs.
  • Coarsesandpaper‘s strong suit is the rough shaping of wood and the removal of previous finishes, such as light coats of polyurethane. Coarse grits are typically in the 40- to 50-grit range.
  • Mediumsandpaper, ranging from 60- to 100-grit, accommodates some final shaping. Primary sanding of rough wood and the removal of planning marks on wood is often best done with medium-grit sandpaper.
  • Fine sandpapers range from 120- to 220-grit. For most home workshops, this sandpaper will suffice for final sanding before the work is finished.
  • Extra finesandpaper is often used between coats of paint or varnish. Grits of 240, 320 and 400 are termed very fine, while extra- or superfine sheets with grits of up to 600 are best-suited for polishing jobs.

Note: On many projects, you’ll start with a coarse sandpaper grit, and then switch to finer grits to obtain a smooth finish.

Choosing Grit Material

Not only does the density of sandpaper grit make a difference in the success of your sanding project, but the type of abrasive material does, too. Some types of grit grain are better suited to smooth and sand types of materials (wood versus metal, for example). Most manufacturers list the type of material best suited for sanding on their product labels, but it’s Smart to know what type of grit to look for before you shop.

  • Flint: A natural grain, flint is durable and well suited for sanding off surface products, such as old varnish or paint.
  • Emery: A natural grain, emery sandpaper is most often used for removing corrosion and/or polishing steel and other metals. The edges of its particles can be too sharp for sanding wood.
  • Garnet: Another natural grain, garnet is slightly softer than flint or emery, so it tends to dull relatively quickly when used to sand metal. It’s best-suited for fine sanding of wood.
  • Zirconia alumina: A synthetic product, this grit is long-lasting and well-suited for grinding away burrs on metal and for an initial sanding of rough wood. When sanding metal with zirconia alumina, the grit particles can actually become sharper, so you won’t have to change sandpaper frequently.
  • Aluminum oxide: Another very durable synthetic grit, aluminum oxide is well suited for sanding and polishing various types of metal, including bronze and alloy steel, in addition to being a good choice for sanding all types of hardwoods.
  • Silicon carbide: The most durable of all synthetic abrasives. Silicon carbide is good for sanding a wide range of materials, including plastic, metal, hardwoods, and softwoods.

Working with the Right Tools

Sandpaper is very versatile by itself: You can fold a sheet into a palm-sized square, sand until the grit dulls, and then refold it for a fresh sanding surface. If you have a lot to sand, however, you may be better off making use of one or more popular sanding tools. Even with these instruments, choosing the right sandpaper grit and type for the job still applies.

sanding, grinder, angle, sander, sandpaper
  • Manual hand sander: This inexpensive tool features a pad, often made from rubber; side clamps to secure the sandpaper; and a handle that allows the user to move the sander quickly and easily. Manual hand sanders are great when you need to sand large areas, such as the side of a bookcase that would take much longer if you were sanding with a piece of folded sandpaper.
  • Sanding sponge: Made from a flexible sponge that’s covered with sanding grit, the suppleness of a sanding sponge allows the user to sand rounded edges uniformly just by pressing the sponge on the edge while sanding. Some sanding sponges come with a beveled side that helps with sanding in tight spots, such as around the base of stair balusters.
  • Vibrating palm sander: This corded power sander is small enough to hold in one hand and you can choose from a variety of sanding plate shapes, including square and rectangular for sanding open areas, or triangular for sanding in hard-to-reach spots. Just attach sandpaper (some types of palm sanders accept only pre-cut sanding pads) and flip the switch on—the powerful vibrations do all the sanding work, you only need to guide the sander.
  • Orbital sander: True to its name, this power sander moves in a circular, orbital pattern, which should not be construed as spinning. Imagine placing your palm flat on a table and moving it in a series of small circles—that’s the same motion an orbital sander makes. Orbital sanders, depending on the size and brand, accept either cut pieces of regular sandpaper, or pre-cut sanding pads, and they are well-suited for sanding flat areas.
  • Random orbital sander: Like a regular orbital sander, a random orbital sander moves in circular patterns, but at the same time, the entire sanding base also moves in an arbitrary side-to-side and back-and-forth pattern. This helps prevent sanding marks that can occur if the sander is held in one place too long. Random orbital sanders have circular sanding plates and usually accept only pre-cut sanding disks.
  • Belt sander: The power belt sander packs a lot of sanding power into a handheld sander that usually requires both hands to operate. Pre-packaged sanding belts (loops) are fitted over two cylindrical drums at the base of the sander. When powered-on the drums spin and the sanding belt moves in a continuous direction. Belt sanders are great for removing old varnish or sanding large rough surfaces, but because the belt moves only in one direction, the user must keep the sander moving at all times. If a belt sander is held in one place, it can quickly create deep sanding marks in the wood.
  • Drum sander: The drum sander features a large cylinder that accommodates a wide sanding belt or loop. When the machine is powered-on, the drum spins, sanding in much the same way as a belt sander. Like a belt sander, the drum sander is also fairly aggressive and care should be taken to keep it in motion to prevent sanding marks.
  • Bench-mounted sanders: Sanders that mount permanently to your workbench are mainly used for small woodworking projects. Bench-mounted sanders incorporate one of the above sanding methods; they will vibrate, spin or sand by means of a belt or drum. Instead of moving the sander, the user moves the wood that’s being sanded when operating bench-mounted sander.
  • Floor sanders: Floor sanders feature large belts, drums, or orbital sanding plates that can efficiently remove old varnish on hardwood flooring or grind down warped wood flooring. These powerful machines make quick work of sanding, but they must be operated with care to keep from damaging the wood floor.

The Best Sandpaper, Grinding Blocks, and Abrasives for Pottery and Ceramics

In ceramics, there’s always a need to sand something. Whether it is cleaning the foot of a pot or dealing with a massive glaze run on a kiln shelf, there are a few different tools that will really take care of these problems in effective, safe, and economical ways. This post will cover the best abrasives, sandpaper, and grinding blocks, as well as how to use them. You probably won’t need every single one of these tools, but they’re covered here so that you can find what will work best in your studio.

Safety note: Keep in mind that any sort of sanding or grinding can produce dust. Wear a dust mask or respirator, or when possible, sand wet.

Most Used / Top Pick: The thing I reach for the most is the plastic-backed, purple, pro-grade sandpaper made by 3M. (Pictured at top) It is economical, long lasting, and can be used wet. It’s a simple, versatile tool that has a place in any studio.

Sandpaper

There are two sandpapers that I use in the studio: 3M Pro Grade Sandpaper and Emory Cloth. Other sandpapers, such as those designed for wood, don’t hold up under the heavy use needed with ceramics and clay. One advantage of sandpaper, as opposed to solid blocks, is that it is flexible and can be bent, creased, or cut into a variety of shapes if you need to sand hard-to-reach spots.

3M Pro Grade Sandpaper

The purple, plastic-backed 3M Pro Grade Sandpaper is the main tool in my sanding arsenal. It lasts longer than other sandpapers and can be used wet or dry. The plastic backing is advertised as “no-slip grip” and it is easy to hold and control, even when wet.

The paper measures 9 x 11 inches and is available in a variety of grits. I generally stock 80 and 150 grit, but a range of 4 grits from 60 to 220 would probably cover most needs.

The sandpaper can be found in smaller packs ranging from 3 to 6 sheets, or bulk packs with 20 or 100 sheets. 20 sheets will last a long time for individual use, or around 6 months for a busy academic or community studio.

Emory Cloth Sandpaper

Emory Cloth is a cloth-backed sandpaper that can also be used wet or dry, and the cloth backing makes it long-lasting and economical. Emory cloth can be found in sheets or in rolls. It is especially ideal for sanding the bottom of pots when they come out of the glaze firing, to clean up any small burrs or imperfections, or to remove kiln wash.

For emory cloth, I like to buy rolls so that I can cut or rip off just what is needed.

Grinding Blocks

There are a variety of grinding blocks that are useful in the ceramic studio. A block might be used in place of sandpaper, but I usually stock both sandpaper and blocks. The bigger blocks are especially useful for dealing with glaze drips and cleaning kiln shelves while a whetstone can be used to sharpen tools and clean up pots.

Silicon Carbide Rubbing Block

A silicon carbide rubbing block (or grinding block or brick) is one of the most effective ways to deal with glaze drips and to clean up kiln shelves and kiln posts. The blocks come in a variety of sizes, with or without handles, and some have fluting. The fluting is especially useful for grinding rough kiln shelves flat again. A flat-sided block is better for cleaning up the foot of pots or the bottoms of sculptures.

Silicon carbide blocks can be used wet, which is a plus for me because I’m always looking for ways to minimize dust in a studio.

A downside of these rubbing blocks is they are prone to cracking if dropped. This is especially a problem if you crack one with a handle. But don’t despair, the pieces are good until they are ground down to the last bit.

Another downside is they are typically on the rough side, around 20 to 60 grit. This is fine for kiln shelves, but you’ll want to follow up with something a bit finer, such as sandpaper or emory cloth, if you’re sanding the bottom of a pot.

The block with handles are typically 6” x 3” x 1”, but these sizes vary by manufacturer.

Aloxite Blocks and Whetstones

Available at ceramic suppliers, aloxite (aluminum oxide) blocks are smooth, hard, and extremely durable blocks. They are very long lasting, they don’t “shed” a lot of material when used, and they are especially great for sanding the bottom of pots.

Alternately, and easier to find, you can use whetstones designed for sharpening knives. Generally not as hard as aloxite, whetstones are another great option for cleaning small glaze runs, burrs, or rough patches on fired ceramic. They can also be used to sharpen studio tools, such as scissors or fettling knives.

Neither of these smaller blocks are particularly good for cleaning large areas of kiln shelves, but they’re great to use on pots.

Both aloxite stones and whetstones can be used wet, which keeps dust out of the air.

Diamond Hand Pads

Diamond hand pads are the perfect way to sand away burrs, small glaze drips, and rough patches on pots, sculptures, or kiln shelves and posts. Made of industrial-grade diamonds embedded in plastic, these are available from a variety of manufacturers as either soft, flexible pads or semi-hard, foam-backed pads. The foam-backed pads are my favorite because they provide structure and support your hand, but the flexible pads are useful for sanding more complicated shapes. Available as sets or individual pads, my recommendation is to get four individual pads in the range of 50 grit, 100 grit, 200 grit, and maybe 400 grit.

The soft pads are available from Diamond Core Tools, while foam backed pads are available from Diamond Core and other manufacturers such as Stadea or various generic names on Amazon. Expect to spend 15 to 30 per pad, but if used just when needed (use sandpaper for more everyday tasks), they should last for some time, maybe even years.

Like many other tools listed here, these can be used wet, which keeps sanding dust out of the air.

Silicon Carbide Grinding Wheels and Cups for Power Tools

If you have a bench grinder or angle grinder, you should get silicon carbide stones that fit these tools. Silicon carbide will grind through material such as glaze and ceramic without producing excess heat, and it’s the appropriate material to use with non-metallic materials including ceramic, stone, and concrete.

This especially comes in to play with using a bench grinder to clean up glaze drips. If it are not using silicon carbide, the wheel and glaze may get too hot, resulting in potentially dangerous melted bits of glaze. Stick with silicon carbide wheels that are properly dressed and kept in shape. (If you don’t have a dressing tool to keep your wheel even, definitely get one of those too.)

For angle grinders, there are also silicon carbide cups that can quickly clean kiln shelves. These are especially useful if you need to take off all the kiln wash and start with a fresh coat. Keep in mind that angle grinders produce a lot of dust, so do use this tool with caution. Or see the recommendation below about switching to a wet grinder for these types of uses.

Wet Grinders

Rather than an angle grinder, which definitely make a lot of dust, consider a wet grinder for quickly dealing with bad glaze runs or cleaning kiln shelves. A wet grinder has a water feed that keeps a stream of water flowing out of the center arbor hole on the grinder. They can spray water and sanded bits all over,, but if you have a tub or large sink to catch the water, it is not that bad.

It’s best to go with a quality wet grinder, such as a Makita or Flex. (I’ve personally been using a Flex brand grinder for about 7 years). If you carefully read reviews, the cheaper wet grinders can give small electric shocks or stop working after some use. For an electric tool that uses water, you definitely want a quality machine that won’t shock you! And while using, be sure to follow every safety protocol. Personally, in my years of using a Flex variable speed grinder, I’ve never felt one tiny shock.

A variable speed wet grinder is the way to go, as that allows you to control the speed. Slower speeds don’t whip as much water around. Wet grinders are generally used with diamond pads. As with hand pads, in my experience a range of grits from 40 or 60 to around 400 get the job done. I’ve had good luck with Stadea pads (shop at Amazon), both the 4 and 5 inch sizes. The lower grits can wear out quickly, depending on use, so you may want to order a few of those. I originally purchased an entire set that goes all the way up to 3000 and buff, but for cleaning up glaze drips, 400 suits me, so I prefer to purchase individual pads to use with the wet grinder.

One drawback with wet grinders is figuring out the right hose connection. Expect to make a few trips to the hardware store to find the right fittings to connect your wet grinder to a hose or faucet.

Sanding Tips and Tricks

A few ideas to put into practice in your studio:

  • Broken pieces of kiln shelves, especially silicon carbide shelves, make excellent sanding blocks and stones.
  • Rub the bottom of two pots together for a quick post-firing sanding / cleanup. This can be done wet under running water or dip quickly into a bowl of water.
  • A set of sharp chisels and a rubber mallet can help in removing glaze drips from kiln shelves, then follow up with sanding tools.
  • Check out our tutorial for a DIY Interchangeable Grinding Disc
  • Whenever possible, sand wet! It’s the safest way to keep dust out of the air.

Safety Note

Any type of sanding, grinding, or rubbing will create dust. Take appropriate precautions with wearing dust masks or respirators, and eye protection too, when sanding or using power tools.

Summary

This post has covered and reviewed a variety of sanding and grinding tools and abrasives for use with ceramics and pottery.

My most-used tools are sandpaper and a silicon carbide rubbing block, but I also have a wet grinder with diamond pads and hand pads. I also keep broken pieces of kiln shelves to use as grinding tools. All of this is done wet, when possible, or I use proper safety protection such as a dust mask and safety glasses when sanding. Sanding, grinding, and cleanup are an inevitable part of working with fired ceramic and the best tools will get the job done for you in a safe, effective, and long-lasting way.

What sanding or grinding tools do you use in the studio? Let us know in the Комментарии и мнения владельцев.

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