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20-Inch Diamond Blade

by Blades Admin

20 Inch Diamond Blade: Ultimate Guide for Cutting Concrete, Asphalt, Masonry & Stone

A 20 inch diamond blade is one of the most versatile and high-performance cutting tools used across construction, masonry, landscaping, and industrial applications. Its large cutting diameter, diamond-embedded segments, and engineered core allow it to handle demanding jobs where smaller blades simply fall short. Contractors, fabricators, and equipment operators rely on 20 inch diamond blades when they need deeper cuts, faster production, and consistent results on tough materials like cured concrete, reinforced concrete, asphalt, stone, block, and composite materials.

This guide dives into everything you need to know—from blade types and segment designs to applications, compatibility, cutting depth, cooling methods, safety, and performance tips—so you can choose the right blade and get the best possible results on the job.

What Makes a 20 Inch Diamond Blade Different?

A 20 inch diamond blade stands out due to its large diameter and heavy-duty build. The 20-inch size provides significant advantages:

  • Deeper cutting depth: Ideal for thick slabs, large blocks, and deep trenching.

  • Higher stability: Larger diameter reduces deflection during long cuts.

  • Better cooling: More surface area helps dissipate heat.

  • Greater productivity: Cuts more surface area per rotation compared to smaller blades.

Professional crews choose 20 inch blades when they need a reliable, high-output blade for continuous or high-stress cutting.

Common Uses for a 20 Inch Diamond Blade

This blade size is preferred in mid-to-large construction equipment and can handle a wide variety of materials. Typical applications include:

Concrete Cutting

A 20 inch diamond blade is a top choice for:

  • Cured concrete slabs

  • Reinforced concrete with rebar

  • Sidewalks, driveways, foundations

  • Concrete pipes and precast structures

Contractors often use these blades on walk-behind saws, slab saws, and floor saws for deep, precise cuts.

Asphalt Cutting

For road work, trenching, and utility repairs, a 20 inch blade with a softer bond delivers fast cutting through asphalt, blacktop, and abrasive road materials.

Masonry & Block

Blades in this size easily cut:

  • CMU block

  • Pavers

  • Brick

  • Limestone

  • Sandstone

The large diameter is ideal for production environments like block yards or job sites requiring repetitive cuts.

Stone & Hard Materials

With a properly bonded blade, you can cut:

  • Granite

  • Marble

  • Bluestone

  • Quartzite

Segments for stone cutting generally feature harder bonds and premium diamonds.

Demolition

A 20 inch diamond blade is strong enough for demolition cutting, including structures reinforced with rebar, wire mesh, and layered materials.

Different Types of 20 Inch Diamond Blades

Choosing the right blade requires understanding segment bonding, rim design, and intended use.

1. Segmented Rim Blades

These feature gullets between segments for airflow and cooling.

  • Best for: Concrete, masonry, general construction

  • Strength: Fast cutting and durability

Segmented blades are the most common 20 inch blades thanks to their versatility and heat management.

2. Continuous Rim Blades

These have a smooth edge with no segment breaks.

  • Best for: Tile, porcelain, marble, delicate stone

  • Strength: Clean, chip-free cuts

Continuous rims aren't typically used on walk-behind saws due to heat buildup but are valuable in specialized stonework.

3. Turbo Rim Blades

A serrated, grooved design improves cooling and speed.

  • Best for: Concrete, brick, stone

  • Strength: High-speed cutting and balance

Turbo blades combine smoothness with cutting aggression.

4. Laser-Welded Blades

Laser-welded segments offer the strongest attachment.

  • Best for: Heavy-duty concrete and asphalt cutting

  • Strength: Maximum durability and heat resistance

These are the contractor-grade choice for demanding applications and long cutting sessions.

Bond Hardness: Why It Matters for Performance

Diamond blades rely on the bond—the metal matrix holding the diamonds—to control how fast diamonds are exposed and replaced.

Soft Bond

  • Fast wear

  • Exposes new diamonds quickly

  • Best for abrasive materials like asphalt

Medium Bond

  • Balanced wear and durability

  • Best for standard concrete

Hard Bond

  • Slow wear

  • Prevents premature erosion

  • Best for granite, cured concrete, and hard stone

Selecting the correct bond ensures the blade cuts efficiently rather than glazing or wearing too fast.

Cutting Depth of a 20 Inch Diamond Blade

A typical 20 inch diamond blade offers a maximum cutting depth of about 7–7.5 inches, depending on the saw and arbor size. This makes it ideal for:

  • Thick foundations

  • Deep utility trenches

  • Road cutting

  • Heavy pavers and large stone blocks

Walk-behind saws and floor saws often maximize this depth for efficient production.

Wet vs. Dry Cutting

A 20 inch blade may be designed for wet, dry, or combined use. Most professional contractors choose wet use for large diameter blades.

Wet Cutting Advantages

  • Reduces friction and heat

  • Extends blade life

  • Minimizes dust

  • Delivers smoother cuts

Dry Cutting

Used when water access is limited. Requires careful control of:

  • Pass depth

  • Cool-down periods

  • Saw load

Always check the blade’s rated usage before operation.

Choosing the Right 20 Inch Blade for Your Saw

A 20 inch diamond blade is commonly used on:

  • Walk-behind concrete saws

  • Floor saws

  • Masonry table saws

  • High-horsepower gas saws

  • Industrial cutting machines

Before choosing your blade, verify:

  • Arbor size: Common sizes include 1" and 20mm.

  • Saw horsepower rating: Higher HP requires stronger cores and segments.

  • RPM rating: A 20 inch blade typically runs around 2,200–2,500 RPM depending on design.

Always match the blade to the saw for optimal performance and safety.

Segment Height and Lifespan Considerations

High-quality blades often feature segment heights ranging from:

  • 10mm (standard)

  • 12mm (extended life)

  • 15mm–20mm (premium long-life segments)

Thicker segments mean:

  • More diamond material

  • Longer lifespan

  • Better performance for deep or prolonged cutting

Contractors looking for long-term value often choose higher segment heights.

Best Materials to Cut with a 20 Inch Diamond Blade

A premium, properly bonded 20 inch blade can handle:

Concrete

  • Cured

  • Green

  • Reinforced

  • High PSI mixes

Asphalt

  • Standard

  • Abrasive mixtures

  • Chip seal

Stone

  • Granite

  • Marble

  • Travertine

  • Slate

Masonry

  • Brick

  • Pavers

  • Block

  • Precast

Choosing the correct blade composition ensures smooth, efficient cutting.

How Long Does a 20 Inch Diamond Blade Last?

Blade life depends on:

  • Material hardness

  • Saw horsepower

  • Cutting speed

  • Cooling method

  • Segment height

On average, a contractor-grade 20 inch blade may last:

  • 100–300 linear feet on reinforced concrete

  • 300–600 linear feet on asphalt

  • 300–800+ linear feet on standard concrete

Premium laser-welded blades with tall segments last significantly longer.

Performance Tips for Getting the Most Out of Your Blade

To maximize blade life and productivity:

1. Use Proper Cooling

If cutting wet, maintain steady water flow to both sides of the blade.

2. Match the Blade to the Material

Don’t use a hard-bond blade on asphalt or a soft-bond blade on granite.

3. Avoid Excessive Pressure

Let the diamonds do the cutting—too much force can glaze the segments.

4. Make Straight, Controlled Cuts

Twisting or binding stresses the blade and the saw motor.

5. Allow Cool-Down Periods When Dry Cutting

This prevents overheating and segment loss.

6. Ensure Proper Saw Maintenance

A misaligned saw can destroy even the best blade.

Safety Tips When Using a 20 Inch Diamond Blade

Due to its size and power requirements, safety is critical.

  • Wear protective equipment (glasses, gloves, boots).

  • Never exceed the maximum RPM.

  • Inspect segments for cracks or damage before each use.

  • Make sure the blade is securely mounted.

  • Keep hands, clothing, and cables clear of the blade path.

  • Always allow the saw to reach full speed before contacting the material.

A well-maintained blade ensures both productivity and safety on the job.

Conclusion

A 20 inch diamond blade is a vital tool for contractors working on concrete, asphalt, stone, and heavy-duty masonry. Its deep cutting capacity, segment strength, and versatility make it essential for professional construction applications. By choosing the correct bond, segment design, and cooling method—and matching the blade to your saw and material—you’ll achieve faster cuts, longer blade life, and precise results.

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