Fiber discs for angle grinders, 115 & 180 mm, corundum

Corundum fiber discs for angle grinders—the proven all-rounder for metal, wood, and paint

At Riwo Commerce, you’ll find high-quality corundum fiber discs for all standard angle grinders—available in the standard diameters of 115 mm and 180 mm. Our vulcanized fiber discs are the universal solution for professional work on steel, aluminum, wood, paint, and plastics—anywhere reliable material removal and good value for money are required. Shipping directly from the manufacturer-importer, we often offer prices 30% lower than German brand manufacturers while providing comparable or superior quality.

What are fiber discs? The go-to choice for professionals using angle grinders

Fiber discs—also known as vulcanized fiber discs —consist of an extremely sturdy, multi-layered fiber backing with abrasive grit applied to it. The vulcanized fiber backing is created by compressing multiple layers of paper with special binders; once cured , it is extremely robust, dimensionally stable, and heat-resistant. This makes fiber discs the top choice for tough, intensive sanding jobs:

• High grinding performance — reliable material removal with controlled heat generation
• Durable and tear-resistant — remains stable even under lateral pressure
• Versatile — metal, wood, paint, plastic
• Long tool life — fewer tool changes, greater efficiency

Corundum (aluminum oxide) — the tried-and-true all-rounder

Our fiber discs are made from high-quality corundum aluminum oxide —the most widely used abrasive grain in the professional sector. Corundum is a tried-and-true classic that offers the best value for money of all abrasive grains and stands out for:

• Versatile applications: Suitable for metal, wood, paint, plastics, and many other materials
• Great value for money: The economical choice for workshops and DIY enthusiasts
• Reliable material removal: Consistent grinding performance throughout the entire service life
• Proven grinding quality: The industry standard for decades
• Versatile: Suitable for everything from rough grinding to fine sanding

Unlike specialized premium abrasive grains such as zirconia corundum (which is more suited for specialized stainless steel applications) or ceramic (for heavy-duty steel machining), corundum is the professional all-rounder for everyday use —and offers unbeatable value for money.

Two standard sizes for every angle grinder

📏 115 mm diameter — the handy all-rounder

The most common size for standard angle grinders in workshops and on construction sites. Ideal for detailed work, repairs, DIY projects, and sanding in hard-to-reach areas. Standard shank with a 22.23 mm bore—fits any standard angle grinder with an M14 thread.

📏 180 mm diameter — the professional size for large surfaces

The industry standard for high-performance angle grinders and large-scale grinding jobs. Rapid material removal over large areas—ideal for workshops, steel construction, woodworking shops, and industrial applications. Standard mounting with a 22.23 mm bore.

💡 Important: Always observe the maximum permissible speed for your fiber disc (indicated on the disc or packaging) and never operate the angle grinder at speeds higher than this—otherwise, there is a risk of breakage.

Complete range of grit sizes from K16 to K100

We offer both diameters in 8 grit sizes —from extremely coarse grinding to fine finishing:

• K16 (Extra Coarse): Maximum material removal — heavy-duty rust removal, thick weld beads, paint and coating removal
• K24 (Very Coarse): Coarse removal in metalworking, removal of thick layers of material
• K36 (Coarse): Standard for coarse sanding of metal and wood
• K40 (Coarse–Medium-Coarse): General-purpose material removal, ideal for standard applications
• K50 (medium-coarse): Transition grit — combines coarse removal with a uniform finish
• K60 (medium-coarse): Standard grit size for medium-grit sanding and transition work
• K80 (Medium): Finer grit, for preparing smooth surfaces
• K100 (Fine): Fine sanding for smooth surfaces, preparation for further processing steps

💡 Pro tip: For best results, we recommend sanding in stages: Start with a coarse grit (e.g., 24-grit or 36-grit) and work your way up through 60-grit to 80-grit or 100-grit for a smooth finish.

Important: A support plate is required

Fiber discs are not attached directly to the angle grinder, but rather to a backing pad with an M14 thread. The backing pad ensures even pressure distribution, protects the disc from breaking, and is essential for achieving the optimal grinding angle. Be sure to use a backing pad that is suitable for the specific disc size:

• For 115 mm fiber discs: 115 mm backing pad with M14 thread
• For 180 mm fiber discs: 180 mm backing pad with M14 thread

Typical applications

• Metalworking: Grinding, deburring, and smoothing of steel, aluminum, and other metals
• Weld Be ad Finishing: Removal of weld beads, smoothing, and finishing — K36 for coarse, K60 for fine
• Rust Removal & Paint Stripping: Quick Surface Preparation — K16 to K36 for Heavy-Duty Material Removal
• Woodworking: Rough sanding of solid wood, paint removal from furniture and doors
• Paint and Varnish Removal: Effectively removing old layers of paint from metal, wood, or stone
• Bodywork Preparation: Sanding for Painting and Repair Work in the Automotive Industry
• Filling work: Smoothing and plastering large surfaces
• Construction & Renovation: Versatile use indoors and outdoors

Direct from the manufacturer-importer — professional quality at fair prices

As a manufacturer-importer, we produce our products in our own factories and ship them directly to Germany— with no middlemen and no markups. This means we are often 30% cheaper than German brand manufacturers, while offering comparable or even better quality. We already supply well-known specialty retailers in southern Germany—a clear sign of confidence in the quality of our products.

Who are our corundum fiber discs designed for?

• Locksmithing & Metalworking: Versatile for use in metal repair and fabrication work.
• Welders & Metalworkers: Ideal for weld bead finishing and standard metal grinding.
• Body shops & auto repair shops: Efficient surface preparation for painting and repair work.
• Carpentry & Woodworking: Rough sanding, paint removal from furniture and doors.
• Painters & Body Shop Technicians: Removal of old coatings prior to repainting.
• Renovation and restoration companies: Versatile abrasives for any surface.
• Workshops & DIYers: Proven quality, even in small quantities — no minimum order.
• Wholesalers & Resellers: Attractive B2B terms available upon request.

Frequently Asked Questions About Fiber Discs

What is the difference between a fiber disc and a cutting disc?

A cutting disc is designed for cutting material—thin, hard, and built for side-cutting. A fiber disc is a flat grinding disc for surface finishing—it removes material across a wide area rather than cutting it. Both are used on an angle grinder, but they have completely different applications.

Why do I need a support plate?

The backing pad (also known as a grinding pad) serves three important functions: It securely holds the fiber disc in place on the angle grinder (M14 thread), distributes the contact pressure evenly, and protects the disc from breaking under load. The fiber disc cannot be used safely without a backing pad—it is an essential piece of equipment.

What exactly is vulcanized fiber?

Vulkanfiber is a particularly robust type of backing material made from multi-layered compressed paper that is bonded with adhesives to form an extremely stable, compact substrate. Once cured, Vulkanfiber is so robust that it can withstand high mechanical and thermal stress—making it perfect for grinding wheels.

How does corundum differ from zirconia corundum?

Aluminium oxide (corundum) is the universal standard abrasive grain—tried and tested, versatile, and offering the best value for money. It is suitable for nearly all materials: metal, wood, paint, and plastic. Zirconia corundum is a more specialized, more expensive abrasive grain with a self-sharpening effect—particularly advantageous for stainless steel and hard metals, but often unnecessary for standard applications. For everyday use in the workshop and on the job site, corundum is usually the most economical choice.

What grit size is right for my application?

For rough material removal (weld seams, rust, thick layers of paint): K16 to K36. For standard grinding: K40 to K60. For finer grinding (surface preparation, smooth finishes): K80 to K100. A step-by-step refinement—e.g., K24 → K60 → K80—delivers the best grinding results.

Are the discs suitable for aluminum?

Yes, corundum fiber discs are generally suitable for aluminum and non-ferrous metals as well. When working with aluminum, we recommend using a lower contact pressure and a slightly finer grit (K40 or higher) to prevent the disc from becoming clogged. For frequent aluminum processing, a release agent or special aluminum abrasive grit can further extend the service life.

What is the maximum permissible speed?

The maximum permissible speed is indicated on each fiber disc or on the packaging. It depends on the diameter—smaller discs (115 mm) can operate at higher speeds than larger ones (180 mm). Never exceed the specified maximum speed—otherwise, there is a serious risk of breakage. If in doubt, check the manufacturer’s specifications on the disc.

Can I also use corundum fiber discs on wood?

Yes, corundum is ideal for wood—unlike zirconia corundum, which is more suited for metal. When working with wood, corundum fiber discs allow for rapid material removal during rough work (paint removal, furniture restoration) and, with finer grits, produce a uniform finish.

What safety equipment do I need?

When working with fiber discs, safety goggles, an FFP2 respirator (to protect against fine dust), ear protection, and cut-resistant gloves are absolutely essential. Before each use, check the disc for cracks or damage, and always use the angle grinder with a guard in place.

How quickly will my order be delivered?

All standard fiber discs are in stock at our Taufkirchen facility (near Munich) and are typically shipped within 24 hours.

Do you also offer bulk containers or special grit sizes?

For large-scale projects and industrial applications, please feel free to contact us directly. As a manufacturer and importer, we can flexibly accommodate your specific quantities and requirements.