Contents
Introduction
When it comes to choosing the best abrasive product for your sanding job, it’s important to consider the backing the grain is on – because sandpaper doesn’t just come in paper anymore. Why does it matter? Because using the wrong backing type can result in ineffective and inefficient sanding, poor finish and torn or broken abrasive products – meaning you’ll spend more time and money to get the job done right.
The most common types of backings on the market are paper, cloth and film, though there are also mesh and sponge backed products, which are becoming more and more popular. Within each material, there will also be different thicknesses or weights that will work best depending on the application.
In this article, we’ll discuss some of the advantages and disadvantages of the different types and what to consider when choosing your products. Alright… Let’s go.
Paper
Paper products (i.e. traditional “sandpaper”) come in a variety of weights, ranging from A to G, A being the lightest and most flexible, and G, the thickest, most sturdy paper. The paper weight is determined by the physical weight of the original ream of paper.
While paper backing is the lightest and most widely used option, it is also the weakest of the backing materials used for coated abrasives. The benefit of that being that it’s usually the most affordable option available.
Paper products are generally ideal for flat sanding applications and will often provide the best finish. And, while paper can be somewhat flexible at lighter weights, allowing it to match the contours of a workpiece, it can also be very prone to tears, making it potentially less suitable for certain applications.
On the other hand, because paper is pretty light, it may generate less heat, providing a cooler, and therefore more effective, sanding job. Generally speaking, paper products cannot be used for wet application, unless it has been specially treated.
|
|
Paper is best used for light to medium sanding applications, such as cork, wood, lacquers and textiles. Paper products are available in most formats, including belts, discs and sheets. Lighter papers are good for hand sanding, while heavier weights are good for machine sanding.
Advantages:
- Paper is often cheapest
- Available in a variety of weights/thicknesses
- Creates less friction and less heat
- Creates a good finish
Disadvantages:
- Can tear/rip
- Can’t be used for wet applications unless specially treated
Best case applications:
- light to medium sanding applications (like cork, wood, lacquers and textiles)
- Weights A-C – hand sanding, not suitable for belts/machine sanding
- Weights D-G – machine sanding
Related Products:
Fabric/Cloth
Fabric, or cloth, backed abrasives may be made from a variety of different types of woven fibers, both natural, like cotton, and synthetic, like rayon, nylon and polyester. The pattern of the weave in the backing varies from fibers woven at 90 degree angles to fibers overlaid at 90 degree angles and stitched together.
Cloth-backed abrasives come in different thicknesses/weights that carry different levels of flexibility/sturdiness, including JF, J, X, YY. Because they are more durable and tear resistant, cloth-backed abrasives are typically more expensive than paper, but they will last longer and can withstand continual bending and flexing during use. Products with a more flexible and lightweight fabric are good for finishing applications, where heavy stock removal is not the goal. On the other hand, heavier and sturdier fabrics are good for applications in which high stock removal and high pressure is needed, as well as for metal and harder surfaces. Another benefit is that cloth products can also be used with oil and grease, making them useful in wet polishing applications. Cloth backed abrasives are most frequently found on belts, though there are also some sanding discs or sheets available in cloth.
Cloth Weights for Sanding:
JF – most flexible cloth, good for hand and machine sanding of complicated profiles
J – flexible cloth (like denim), good for hand and machine sanding of profiles
X – strong, stiff cotton cloth, good for heavy duty machine sanding
YY – stronger than x cloth, made of polyester, good for heavy duty machine sanding when extra stock removal is necessary
Advantages:
- Available in a variety of weights/stiffnesses
- Tear resistant
- Can be used with oil and grease
Disadvantages:
- More expensive than paper
Best case applications:
- High stock removal
- Metal and hard surfaces
- Applications that require a flexible abrasive that won’t tear
Related Products:
Film
A recent development in coated abrasives, the film backing is made of a uniformly thick plastic sheet that provides both flexibility and durability. The plastic is not likely to tear, while also being soft enough to mold to precision shapes. While some might consider film products to be the best of both worlds, the downside is they often cost more than paper. (Our Filmtek discs are a great option, however, for those looking for film on a paper budget.)
Film products are also waterproof and can be used for wet sanding applications, such as in the metalworking or automotive industries, where there may be contours and very fine polishing applications. Film products are available in discs and sheets for hand sanding and orbital sanding applications.
|
|
Advantages:
- waterproof, can be used for wet sanding
- flexible, can match contours
- lasts longer than paper
- tear resistant
Disadvantages:
- often costs more than paper
Best case applications:
- wet sanding
- metal and automotive
- sanding contours and shapes
Related Products:
Mesh / Net
Net-backed products are a less-common solution based on a mesh or screen pattern. These products are great low-pressure applications and certain products can also be used for wet applications. Due to the screen-like construction, they provide maximum dust extraction and a cooler sanding experience that reduces loading – making the product last longer. Mesh products are primarily used on orbital disc and sheet sanders.
Advantages:
- maximum dust removal
- reduced heat and loading
Disadvantages:
- more expensive material
Best case applications:
- excellent for marine and automotive industries
Related product:
Foam/Sponge
Foam backed abrasives provide an excellent option for sanding odd shapes, moldings, tight spaces and more. Until recently, these products were for hand sanding only, but the newest generation of foam abrasives, like our EKASILK line, comes with a hook and loop backing, allowing them to be used on a sanding machine. Ekasilk Plus, for instance, also comes with venting holes to extract dust with a vacuum, making them ideal for finish sanding and minimizing heat and loading.
|
|
Abrasive sponges are flexible, waterproof and washable, meaning they can be reused, giving them a very long abrasive life. They come in a variety of sizes, thicknesses and grades to meet different needs and are perfect for finishing.
Advantages:
- waterproof, can be used for wet sanding
- flexible and can meet the demands of complex profiles and curves
- washable
- versatile (come in many combinations of grit, grain type, and size/thickness)
- can be used to remove sanding flaws from earlier stages, such as swirls and light knife marks
Disadvantages:
- not for leveling
|
|
Best case applications:
- Hand sanding (Uneesponges)
- Use on our Ekasand sanders (Ekasilk sponges)
- Finishing applications, such as between coats of finish
- Contours, Curves
- Tight spaces
Related Products:
Conclusion
When shopping for abrasives, it’s always important to consider your application in making your selection for the ideal product. One major consideration in that process will be the backing material, whether paper, cloth, mesh, film or sponge. Certain materials are available for all machine formats, from belts to discs and sheets, while others are only available in one format or another. When selecting your abrasive, some of the most important variables to consider in your application are: the substrate of your work piece, will you be wet sanding or dry sanding, will it be flat or have contours, will you be rough sanding or finishing, what kind of sander are you using, and so on.
If you need assistance in making your abrasives selections, contact our sales team for personalized recommendations.
