Product Specification
4" X 5/8"-11 KNOTTED CUP BRUSH - STAINLESS STEEL
When stainless surfaces need aggressive cleanup across a larger working area, the 4" x 5/8"-11 Knotted Cup Brush - Stainless Steel delivers the stiffness and coverage needed for heavy rust, scale, weld residue, oxidation, paint, coatings, and stubborn buildup. Built with 0.020" stainless steel wire, it is designed for demanding fabrication and maintenance work where a smaller cup brush or flexible crimped wire may not remove material fast enough.
The knotted wire construction bundles the wire into stiff, tightly twisted sections that maintain a firm working edge under load. Combined with the larger 4" cup profile, that gives the brush a broad, stable contact area for cleaning stainless plate, weldments, fabricated components, structural assemblies, and other larger surfaces.
Its 4" diameter provides greater surface coverage for production cleaning, while the 5/8"-11 threaded arbor allows quick spin-on installation on compatible angle grinders. The current product record publishes a 14,000 RPM maximum rating; because this rating differs from the corresponding carbon-steel 4" cup, verify the RPM marked on the actual brush before use.
Product Specifications
| Specification |
Details |
| Diameter |
4" |
| Wire Material |
Stainless Steel |
| Wire Diameter |
0.020" |
| Wire Style |
Knotted |
| Brush Type |
Cup Brush |
| Arbor |
5/8"-11 Threaded |
| Published Maximum RPM |
14,000* |
*The current product record publishes a 14,000 RPM maximum. Verify the rating marked on the actual brush before use and never exceed the brush-label rating.
Features
-
Aggressive knotted-wire construction for medium- to heavy-duty surface cleaning
-
0.020" stainless steel wire for stainless fabrication and contamination-sensitive work
- Large 4" cup profile provides increased cleaning coverage
- Broad, stable contact area for plate, weldments, fabricated components, and structural assemblies
- Stiffer and more aggressive than flexible crimped-wire cup brushes
-
5/8"-11 threaded arbor for quick spin-on installation
- Published 14,000 RPM maximum rating
- Excellent for weld cleanup, rust and scale removal, paint removal, and stainless surface preparation
- Strong choice for larger fabrication and maintenance jobs where productivity matters
Applications & Performance
The 4" knotted cup brush is built for aggressive broad-surface cleaning. Its larger cup profile places more wire against the workpiece than smaller cup brushes, helping cover bigger areas with fewer passes.
Common applications include:
- Heavy rust and corrosion removal
- Weld cleanup
- Removing weld residue and spatter
- Scale and oxidation removal
- Paint and coating removal
- Cleaning stainless plate
- Surface preparation before welding
- Cleaning larger fabricated stainless assemblies
- Preparing metal before coating or repair
- Structural and industrial maintenance
The larger 4" footprint makes this brush especially effective where production cleaning and surface coverage matter more than tight-access maneuverability.
Use controlled pressure and let the wire tips do the work rather than forcing the brush into the surface.
Materials
Especially suited for:
- Stainless steel
- Stainless steel weldments
- Stainless fabricated components
- Other compatible metals where stainless wire brushing is appropriate
Keep this brush dedicated to stainless steel work when preventing cross-contamination is important. A stainless wire brush previously used on carbon steel can pick up iron contamination and transfer it back to a stainless workpiece.
Store stainless and carbon steel brushes separately for contamination-sensitive applications.
Machine Compatibility
Use this 4" cup brush on a compatible angle grinder with a 5/8"-11 spindle and adequate brush capacity. Verify the rating marked on the brush before use; it must meet or exceed the grinder’s maximum speed.
Compatible examples include:
-
Benchmark Abrasives BMT-AGBC4570_1 — 4-1/2" corded angle grinder; 5/8"-11 spindle; 11,000 RPM.
-
Makita® GA7011C — 7" angle grinder; 6,000 RPM.
-
Makita® GA7021 — 7" angle grinder; 6,600 RPM.
Other machines may be compatible. Use the manufacturer-specified wire-brushing setup and guard, with secure hub engagement and adequate operating clearance. Other grinders meeting these requirements may also be suitable.
Safety Tips
- Verify the maximum RPM marked on the actual brush before use and never exceed that rating.
- The brush's rated RPM must meet or exceed the maximum operating speed of the power tool.
- Confirm the grinder is designed to safely accommodate a 4" cup brush and its operating wire flare.
- Inspect the brush before every use and replace it if damaged, excessively worn, loose, or distorted.
- Confirm the 5/8"-11 threaded arbor is fully seated and secure before operation.
- Use the appropriate grinder guard and maintain adequate clearance around the rotating brush.
- Wear proper PPE, including eye and face protection, hearing protection, gloves, appropriate clothing, and respiratory protection when required.
- Keep bystanders away from the work area and direction of rotation.
- Use controlled pressure. Excessive force bends the wire and can accelerate wire fatigue.
- Allow the grinder to reach operating speed before contacting the workpiece.
- Keep stainless brushes dedicated to stainless work when cross-contamination matters.
- Follow all operating and safety instructions for both the power tool and wire brush.
