The Type R Bristle Disc Guide
Quick-change bristle discs in 1", 2", and 3" — the detail-work tool that cleans, blends, and deburrs the corners, welds, and interior surfaces a flap disc will never reach. Grit & color chart, size selection, and the full Pro-Graad line.
Coated abrasives cut fast on flat, open surfaces and quit the moment the work gets small, curved, or tucked into a corner. Type R quick-change bristle discs are built for exactly that work: detail cleaning and light deburring on contoured, interrupted, and interior surfaces — mounted on a die grinder or drill, swapped in seconds, and cutting cool without changing the geometry of the part.
If you're doing weld cleanup in a tight fillet, deburring a cross-drilled hole, stripping coating out of a slot, or blending a casting where a 4-1/2" disc simply can't fit — this is the format built for it. Here's how these discs work, when they beat coated abrasives, and how to pick the grit and diameter without guessing.
01What A Type R Quick-Change Bristle Disc Is
These aren't sanding discs. Each disc is built from stiff polymer filaments arranged around a central Type R quick-change hub. The abrasive — a ceramic and aluminum oxide blend — is molded through the entire bristle, not coated on the surface. That's the difference that makes them behave nothing like a coated abrasive.
Self-Renewing Cut
As each bristle tip wears, fresh grain is exposed underneath. The disc keeps presenting new abrasive instead of glazing over the way a coated disc does — so you get the same finish from the first pass to the last.
Type R Quick-Change Mount
The Type R hub twists on and off a standard quick-change holder in seconds — no wrench, no arbor nut, no mandrel to thread. Spin off one grit, spin on the next. It's the fastest grit change in the shop, which matters when you're stepping through coarse-to-fine on the same part.
It Conforms — Coated Abrasives Don't
The bristles flex independently and wrap the contour instead of riding the high spots. On a small diameter, that lets you work down into radii, weld roots, corners, and interior surfaces a rigid abrasive rolls right over.
Cool-Running, Won't Load
Bristle discs cut with light pressure and low heat — important on thin stainless and aluminum that discolor and warp under a hot abrasive. And the open geometry sheds paint, adhesive, and coating debris instead of clogging up the way a coated disc does.
02When Type R Discs Beat Coated Abrasives
These are a detail and finishing tool, not a stock-removal tool. They win in the jobs where coated abrasives are the wrong choice:
The work is small, tight, or interrupted. Cross-holes, slots, keyways, lettering, weld roots, inside corners of fabricated parts. A 1" or 2" disc gets into geometry nothing flat can touch.
You need to clean without removing base metal. Stripping paint, rust, weld discoloration, or coating off a part you need to keep dimensionally accurate. The bristles lift the contaminant and leave the substrate.
You're working heat-sensitive metal. The cool, light cut cleans thin stainless and aluminum without the tint and warping a hard abrasive causes.
The coating loads everything else up. Gummy paint, adhesive, and powder coat that clog a coated disc in seconds get thrown clear by the open bristle geometry.
Type R bristle discs clean, blend, and lightly deburr. They are not for heavy stock removal, aggressive weld knockdown, or grinding an edge back — that's a flap disc or grinding wheel job. And for large flat or open areas, you'll clean faster with a bigger disc. Use the right tool for the scale of the work.
03The Bristle Disc Grit & Color Chart
Every grit is color-coded so you can identify it across the bench at a glance. Coarse strips and removes; fine cleans, blends, and polishes. Match the grit to the aggressiveness of the job, then step finer for a better finish.
| Color | Grit | Class | Primary Job |
|---|---|---|---|
| Brown | 36 | Extra Coarse | Heavy coating, thick rust, and hard surface contaminant removal. The most aggressive strip in the line. |
| Green | 50 | Coarse | Coating, rust, paint, and contaminant removal where 36 is more bite than the job needs. |
| Yellow | 80 | Medium | Cleaning, blending, deburring, and surface preparation. The everyday workhorse grit. |
| White | 120 | Fine | Cleaning, blending, finishing, and light deburring without heavy material removal. |
| Red | 220 | Very Fine | Fine cleaning, blending, light deburring, and pre-polishing to set up a final finish. |
| Blue | 400 | Ultra Fine | Fine blending, smoothing, and semi-polishing. The final step before buffing. |
Start with the finest grit that will do the job. It's always faster to step coarser for more bite than to fix the scratch pattern a too-coarse disc left behind. For most cleaning-and-blend work, 80 (Yellow) is where to start.
04Pick The Diameter: 1", 2", 3"
Diameter sets how much surface you cover per pass and how tight a space you can work in. Smaller discs get into detail; larger discs cover ground. All three run on a standard Type R quick-change holder.
The tightest access. Cross-holes, slots, lettering, weld roots, and small interior surfaces. Runs at the highest speed of the three.
The most versatile size and the full grit range, 36 through 400. General cleaning, deburring, blending, and finishing on most parts.
More surface per pass while still conforming to contours. Larger castings, weldments, and panels the 4-1/2" disc is too big for.
Grit Availability By Diameter
Not every grit is offered in every size. The 2" carries the full range; 1" and 3" cover the core cleaning and finishing grits.
| Grit / Color | 1" | 2" | 3" |
|---|---|---|---|
| 36 Brown | — | ✓ | — |
| 50 Green | ✓ | ✓ | ✓ |
| 80 Yellow | ✓ | ✓ | ✓ |
| 120 White | ✓ | ✓ | ✓ |
| 220 Red | — | ✓ | — |
| 400 Blue | — | ✓ | — |
If you want to run coarse strip (36) or the fine finishing grits (220 Red, 400 Blue), that's the 2". The 1" and 3" cover the 50 / 80 / 120 range for detail and coverage respectively.
05Which Grit For Which Job
Heavy Coating & Rust Removal
Thick coatings and heavy rust: 36 (Brown). Standard paint, rust, and coating: 50 (Green).
General Cleaning, Deburring & Surface Prep
The everyday job: 80 (Yellow). Clean, break edges, prep for coating or weld.
Finishing & Blending
Blend a scratch pattern and clean without removing material: 120 (White).
Pre-Polish
Fine blend and setup before a final finish: 220 (Red).
Semi-Polish & Smoothing
The last abrasive step before buffing: 400 (Blue). Smooths and refines the surface without cutting it back.
06The Pro-Graad Type R Line
Six grits, color-coded end to end, ceramic-aluminum oxide throughout. Available diameters shown per grit. All twist onto a standard Type R quick-change holder — multiple pack counts offered on each.
For panels, plate, and large-area cleaning where these are too small, step up to the Pro-Graad 4-1/2" x 5/8"-11 threaded bristle discs that thread straight onto an angle grinder. Same molded ceramic-aluminum oxide, built for scale.
07Mounting, Speed & Safe Use
Mounting: Twist the Type R hub onto a standard quick-change holder until it seats. Most commonly run on a die grinder; a drill with a quick-change holder works for lighter jobs. No arbor nut or mandrel thread required.
Speed: Small discs run at higher RPM than large ones, and each diameter has its own limit. Never exceed the maximum RPM marked on the disc, and match it to a tool rated at or below that speed. A 1" disc tolerates far more RPM than a 3" — check the disc, not just the tool.
Technique: Light, even pressure. Let the bristle tips do the cutting; leaning on the disc wears the filaments without cutting faster. Keep it moving and work debris away from you.
PPE: Eye and face protection, gloves, and hearing protection. Bristle discs can shed filaments and throw the debris they lift — guard up, eye pro on, every time.
08Type R Bristle Disc FAQ
What is a Type R quick-change bristle disc used for?
Detail cleaning, blending, coating removal, and light deburring — especially on small, curved, or interior surfaces where a larger flat abrasive can't reach. They strip paint, rust, and weld discoloration without removing base metal, which makes them ideal for parts that need to hold dimensions.
How is a bristle disc different from a coated abrasive disc?
A coated abrasive is grit glued to a flat backing — it cuts fast on flat surfaces but glazes over, loads up, and only touches the high points of a contour. A bristle disc has abrasive molded through flexible filaments that conform to shapes, self-renew as they wear, run cooler, and clean without removing base metal.
What size and grit should I start with?
For most work, a 2" in 80 grit (Yellow) — it's the most versatile size and the everyday grit for cleaning and light deburring. Go 1" for tight detail, 3" for more coverage, coarser (36/50) for heavy stripping, or finer (120/220/400) for finishing.
Which grits come in which diameters?
The 2" carries the full range: 36, 50, 80, 120, 220, and 400. The 1" and 3" cover 50, 80, and 120. If you need heavy 36-grit strip or the fine 220/400 finishing grits, choose the 2".
What tool do these run on?
A die grinder with a Type R quick-change holder is the usual choice. A drill with a quick-change holder handles lighter jobs. The hub twists on and off in seconds — no arbor or mandrel to thread.
Will they damage thin stainless or aluminum?
They're one of the better tools for it. The cool, low-pressure cut cleans and blends heat-sensitive metals without the discoloration and warping a hard abrasive causes. Use a finer grit and light pressure on thin material.
Built For The Work. Priced For The Worker.
Six grits, three sizes, one quick-change hub. Clean, blend, and deburr the details a full-size disc can't touch.
Shop The Type R Line
