The CMT Forstner Bit - 12mm Diameter, 8mm Shank is a precision-ground boring tool engineered for drilling clean, flat-bottom holes in softwood. Built from super strength SP steel, this right-hand rotation bit delivers long-lasting cutting performance for joinery work, cabinet hardware installation, and creating arched or oval openings at any angle. With a compact 8x30mm shank and an overall length of 3-35/64 in., it fits standard drill chucks and drill press setups where accurate, repeatable plunge boring is required.

Key Features

• Super Strength SP Steel Construction - the bit material provides long-lasting cutting performance, reducing the frequency of replacement and maintaining edge integrity over repeated use in softwood.
• 2 Precision-Ground Cutting Edges - dual cutting edges shear material cleanly at the base of the hole, producing a flat, smooth bottom that is ready for hardware seating without additional cleanup.
• 2 Ground Spurs (V2) - the spurs score the wood fibers ahead of the main cutters, preventing tear-out at the rim of the hole and leaving clean, crisp bore walls.
• Right-Hand Rotation (RH) - standard clockwise rotation is compatible with all conventional drill presses and handheld drills, allowing straightforward use without adapter or reverse settings.
• 8x30mm Shank - the 8mm shank fits a wide range of drill chucks, providing a secure grip that reduces runout and keeps the bit on-center during the full depth of the plunge.
• Flat-Bottom Boring Geometry - designed specifically to produce flat-bottom holes of any size, making it the right tool for precise hinge mortises, bracket niches, and hardware recesses where a twist bit would leave an unusable tapered base.
• Angle-Versatile Design - the bit geometry supports drilling at any angle, enabling oval and arched openings that would be difficult or impossible to achieve with conventional bits.

Why This Product

• Dedicated flat-bottom boring - unlike twist or spade bits that leave a tapered recess, this Forstner bit cuts a true flat bottom, which is essential for flush hinge installation, shelf pin holes, and hardware bracket niches where full bearing contact is required.
• Clean results in softwood without tear-out - the combination of 2 ground spurs and 2 precision cutting edges scores and shears wood fibers in sequence, so bore walls and rims stay clean even in grain-sensitive softwood species.
• Angled and shaped openings on demand - because the rim guides the cut rather than a center point alone, this bit can enter wood at an angle, making it practical for creating arched or oval decorative openings and installation niches that standard boring bits cannot produce.
• SP steel durability for production use - the super strength steel construction means the cutting edges hold up through repeated borings before requiring sharpening, making this bit cost-effective for cabinet shops and finish carpenters who drill flat-bottom holes at volume.

Specifications

• Manufacturer Part Number: 537.120.31
• Brand: CMT Orange Tools
• Product Type: Forstner Bit
• Diameter: 12mm
• Total Length: 3-35/64 in.
• Shank: 8x30mm
• Number of Cutting Edges: 2
• Number of Spurs: 2
• Blade Material: Super Strength (SP) Steel
• Rotation: Right-Hand (RH)

Approved Applications

• Drilling precise flat-bottom holes in softwood
• Hinge installation mortises
• Shelf pin and hardware holes
• Creating niches for brackets, straps, frames, and grids
• Creating oval and arched openings at any angle

Frequently Asked Questions

What is the shank size of this Forstner bit, and what drill chucks will it fit?

This bit has an 8x30mm shank, meaning the shank is 8mm in diameter and 30mm long. It fits any drill chuck that accepts an 8mm round shank, including standard drill press chucks and handheld drill chucks of appropriate capacity.

What material is this Forstner bit designed to cut?

According to the product data, this bit is designed for drilling precise flat-bottom holes in softwood. It is not specified for hardwood, engineered wood, or non-wood materials.

Can this bit drill holes at an angle rather than straight through?

Yes. The bit is designed to create oval and arched openings at any angle, making it suitable for angled entry cuts in addition to standard perpendicular plunge boring.

How many spurs and cutting edges does this Forstner bit have?

This bit has 2 ground spurs and 2 cutting edges. The spurs score the wood perimeter ahead of the main cutters to produce clean bore walls and chip-free rims on the finished hole.