3M
3M 33217 Radial Bristle Brush 6 in 7/16 in 1 Micron Power
Six-inch radial bristle brush with 1-micron ceramic bristles for finishing aluminium, brass, bronze, cast iron, stainless steel and steel on bench or pedestal grinders up to 6,000 RPM
- TypeSanders
- Ceramic bristles resist loading on soft metals
- 6 000 RPM maximum speed matches bench grinders
- 1 micron grade for ultra-fine surface finishing
- Green colour identifies the Type C abrasive
- 1 inch unthreaded hole fits standard spindles
Targeted Surface Finishing
The 3M 33217 radial bristle brush uses ceramic bristles in a green Type C configuration for deburring and cleaning aluminum, brass, bronze, cast iron, stainless steel and steel. It mounts on bench grinders or pedestal grinders via a one-inch unthreaded hole and is rated for a maximum operating speed of 6,000 RPM. The six-inch diameter and 7/16-inch face width suit flat or contoured workpieces.
Machine Compatibility Checks
Verify that your bench grinder or pedestal grinder accepts a one-inch unthreaded hole arbor before ordering. Confirm the tool’s no-load speed does not exceed 6,000 RPM to stay within the brush’s rated limit. Ensure the workpiece material matches the listed metals, as the ceramic bristles are selected for those specific substrates.
Daily Workshop Implications
The unthreaded hole design allows quick changes on compatible arbors without tools, reducing downtime between finishing tasks. Ceramic bristles maintain aggressive cutting action while resisting loading on softer metals such as aluminum and brass. The green colour identifies the Type C grit grade at a glance when multiple brushes are stored together.
Highlights
- Ceramic bristles resist loading on soft metals
- 6 000 RPM maximum speed matches bench grinders
- 1 micron grade for ultra-fine surface finishing
- Green colour identifies the Type C abrasive
- 1 inch unthreaded hole fits standard spindles
Specifications
| Type | Sanders |
|---|---|
| Brand | 3M |
| Model | 33217 |
Questions about this item
Does the 33217 radial bristle brush ship with any mounting hardware or adapters for a bench grinder?
The brush has a 1 in unthreaded hole for direct mounting on a bench or pedestal grinder arbor; no extra adapters are included.
How do I decide between the 1 Micron green brush and other colour grades for aluminium and stainless steel?
Green indicates the 1 Micron grade, designed for fine finishing on aluminium, brass, bronze, cast iron, stainless steel and steel.
What does the 6,000 RPM maximum speed mean when the brush is running on my pedestal grinder?
Do not exceed 6,000 RPM; running faster can cause bristle failure and reduces the safe operating life of the 6 in diameter brush.
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