Sanding discs are available in a variety of different backings, the most common of which are cloth, film, hook & loop, and PSA (Pressure Sensitive Adhesive). Each one is designed to support quality results for certain materials and applications, so choosing the right one for its intended purpose is important for best results. 

In this blog, we compare these four common sanding disc backings and outline how to choose the best material for your next project.

Cloth

Cloth-backed abrasive discs may be made from natural fibers like cotton or synthetic materials like rayon, polyester, and nylon. The backing material has to go through a process that includes shrinking, drying, and stretching in order to gain the flexibility and strength needed for its intended use.

Standard cloth backings have letter codes that indicate their strength and flexibility. Your options are:

  • JF: As the lightest and most flexible cloth backing, F-weight is recommended for sanding workpieces with a more complicated or intricate profile.

  • J: This backing has the flexibility to and durability of jean fabric. Although not rugged enough for stock removal, it ensures a smooth and uniform finish, making it appropriate for curved or contoured surfaces.

  • X: Stiffer and more rugged than J-weight backing, X-weight can be used on abrasives designed for everything from stock removal to finishing and polishing.

  • YY: Being the strongest cloth backing available, Y-weight appears on coarse grit abrasives that perform heavy stock removal or extreme-pressure applications.

If you do a lot of stock removal, work with hard surfaces like metal or hardwoods, or need a more flexible abrasive backing for rounded or contoured profiles, cloth-backed abrasives can deliver the results you need without tearing or deteriorating.

Advantages

  • Durable performance

  • Resists tearing better than paper backing

  • Can be washed to clear away resin and buildup

  • Won’t degrade when exposed to grease or oil

Disadvantages

  • More expensive than paper backing

Film

The backing on film sanding discs is made from thick plastic sheeting that’s durable while remaining flexible enough to match contours without ripping or weakening. While film-backed abrasives cost more than paper, it’s worth the price if you do a lot of wet sanding (e.g. in the automotive or metalworking industry) or work on contoured pieces like car parts. Their waterproof properties also make film discs ideal for marine boat finishing.

Advantages

  • Stiff enough to resist tearing

  • Does a great job on contours

  • Waterproof- ideal for wet sanding

  • Lasts longer than paper backing, so you won’t have to replace your discs as often

Disadvantages

  • More expensive than paper 

Hook & Loop

Like their name suggests, Velcro-backed hook and loop sanding discs have small hooks and loops that make it easy to attach them to your orbital sander. This system makes them equally easy to remove, which is useful when you reuse your discs or need to switch to a different type of abrasive while working. Although removable, they maintain a secure hold during use and won’t slip, break away, or fly off.

Advantages

  • Maintains a secure hold during sanding

  • Easy to switch grits as you move from one sanding level to the next

  • Available in a variety of sizes and grit types

  • Save money by reusing your sanding discs

Disadvantages

  • May come loose from the sander when the hooks wear down

PSA

Sanding discs with a pressure-sensitive adhesive (PSA) are easy to attach to your sander- simply peel away the backing and apply. They can be made from film, cloth, or paper, so you’re likely to find a PSA disc that meets your budget and needs. The cloth and film-backed products are stronger and more tear-resistant, which is ideal for heavy-duty sanding, while paper-backed ones do a good job with lighter sanding and finishing jobs.

One thing to bear in mind with PSA discs is that once you remove them, you can’t put them back on. This is where they differ from hook and loop systems. They are a better investment for larger jobs where you’ll be using the same disc until it wears out.

Advantages

  • Available in a wide range of backing types, from paper to film

  • Secure hold during sanding

  • Meets most budgets

Disadvantages

  • Can’t be reattached after removal

Conclusion

When you’re shopping for sanding discs, always consider which backing is ideal for your application. Paper may cost less, but it’s less flexible and more likely to tear. Film backings are waterproof, so if you work in wet or marine environments, it will bring about the best results. When you sand uniquely-shaped pieces, cloth may be a better choice when you’re at the finishing and polishing stages. Similarly, if you go through multiple levels during sanding, the hook & loop system is preferable to PSA, which is more cost-effective for larger pieces. 

Contact an Industrial Abrasive Specialist

At Fintech Abrasives, we manufacture and sell superior-quality sanding discs with backings that include cloth, film, hook & loop, and PSA. No matter what backing you prefer, we pair it with a premium abrasive that delivers the cut you need during stock removal, finishing, or polishing. If you have questions about any of our abrasives or their recommended applications, speak to an abrasive technician today by filling out our contact form or calling (888) 223-8768.