Weiler
Weiler 12736 Cup Wire Brush 3-1/2 in 5/8-11 Threaded Arbor 9000 RPM
A 3-1/2 in carbon-steel knot wire cup brush with 5/8-11 threaded arbor for right-angle grinders up to 9,000 RPM
- TypeSanders
- Standard twist knot wire removes carbon steel efficiently
- 014 in wire diameter balances aggression and surface finish
- 5/8-11 threaded arbor fits right-angle grinders directly
- 9000 RPM maximum speed suits high-speed grinding tasks
- 3-1/2 in cup diameter covers broad work areas quickly
Cup Brush for Right-Angle Grinders
This Weiler 12736 cup brush mounts on right-angle grinders with a 5/8-11 threaded arbor. Carbon-steel twist-knot wire bristles provide aggressive cleaning and surface preparation. The 3-1/2 inch diameter covers broad areas quickly at up to 9,000 RPM. It suits metal fabrication and maintenance tasks.
For heavy rust and scale removal, not finishing
Professionals removing thick corrosion, weld spatter or paint from carbon steel will find the coarse 0.014 inch wire effective. Users needing a smooth finish, working on stainless steel or aluminium, or requiring a quick-change mounting system should choose a different brush type.
5/8-11 threaded arbor compatibility
The brush fits only grinders with a matching 5/8-11 threaded spindle. Verify your tool's arbor specification before purchase to ensure secure attachment and safe operation at the rated 9,000 RPM maximum speed.
Highlights
- Standard twist knot wire removes carbon steel efficiently
- 014 in wire diameter balances aggression and surface finish
- 5/8-11 threaded arbor fits right-angle grinders directly
- 9000 RPM maximum speed suits high-speed grinding tasks
- 3-1/2 in cup diameter covers broad work areas quickly
Specifications
| Type | Sanders |
|---|---|
| Brand | Weiler |
| Model | 12736 |
Questions about this item
How do I fit the 5/8-11 threaded arbor onto my right-angle grinder and what step is often missed?
Thread the cup brush onto the grinder spindle by hand until the 5/8-11 threads seat fully, then tighten with the supplied wrench while holding the spindle lock; the step often missed is confirming the brush sits flush against the grinder flange before tightening.
When will the carbon-steel knot wire need replacing and how can I tell?
Replace the brush once the 0.014 in wire wears down or the 1 1/4 in bristle length shortens noticeably, which shows as reduced cutting action and visible wire breakage at the knot base.
What is the first limit I will hit if I run this cup brush continuously at high load?
The 9,000 RPM maximum operating speed is the first limit; exceeding it risks wire ejection and brush failure, so keep the grinder at or below that speed during sustained use.
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