SB-3 3/8"*3/4" Cylinder Carbide Burr With End Cut - 1/4" Shank Double Cut

The SB-3 is a 3/8" (9.5mm) cylindrical carbide burr with cutting edges on both the side wall and the end face. That end cut is what separates it from the SA series: the SB-3 can plunge straight into a workpiece and square a flat-bottomed pocket, then profile the wall in the same pass. It is the tool of choice for pocket floors, keyway cleanup, spot facing and weld removal where the bottom of the cut has to be flat.

Why the SB-3 is specified for flat-bottom work

• End cut (ANSI Type B) — teeth across the end face let the burr plunge and produce a flat floor, not a radiused or uncut bottom

• Double cut flutes — smoother cutting action and better chip control than single cut on steel and stainless steel

• Rigid 1/4" shank — takes the axial load of plunging without wandering

• Brazed carbide head — the head-to-shank joint holds under interrupted cuts and vibration

• Consistent 3/4" flute length — predictable depth reference when working to a shoulder

Typical applications

• Squaring and cleaning the floor of a pocket, slot or keyway

• Spot facing and removing weld tacks from a flat surface

• Deburring cross-holes and intersecting bores

• Die and mold repair where a corner must be squared rather than blended

• General weld dressing on mild steel, stainless steel and cast iron

Specifications

Working with an end-cut burr

An end-cut burr cuts on two surfaces at once, so it removes material faster than a side-cutting tool of the same size — and it can also dig in if fed too hard. Feed it in slowly until the end face has established a flat seat, then move laterally with light pressure. Keep the tool moving; dwelling in one spot will burnish the workpiece and load the flutes.

Recommended operating speed

OEM, packaging and MOQ

• Laser marking of your logo and part number on the shank

• Custom plastic box, blister pack or branded carton

• MOQ from 20 pcs per size; mixed-size assortments accepted

• Samples for approval before mass production

• Lead time: 7–15 days for stock sizes, 20–25 days for OEM packing

FAQ

Q: When should I use SB-3 instead of SA-3?

A: Use SB-3 whenever the bottom of the cut has to be flat — pockets, keyways, spot faces, weld removal on a plate surface. Use SA-3 when the end must not cut, for example when grinding against a shoulder.

Q: Can the SB-3 plunge cut?

A: Yes, that is its main advantage. Feed in slowly until the end face seats, then move sideways with light pressure.

Q: What speed is safe for a 3/8" head on a 1/4" shank?

A: 22,000–35,000 RPM. Higher speeds increase vibration and the risk of carbide chipping without improving removal rate.

Need the SB-3 in bulk or with your own branding? Send your specification and quantity — samples and OEM packing are available.

Other Available Sizes Related to Type B Carbide Burrs Both in Metric and Inch Standard:

Customization:

1. Please send us the drawings or other important information if you need non-standard carbide burrs.
2. Please contact us if you need more information about type B burrs or other shapes of burrs.
3. OEM is avaliable.

Cut Selection Guide:

STANDARD CUT(M)	STANDARD DOUBLE CUT (X)	WIDE CUT (C)	FINE CUT (F)	ALUMINUM CUT(W)	DIAMOND CUT(D)