Why Tooth Geometry Matters
The tooth geometry of a TCT saw blade determines how each tooth interacts with the material. The angle of the cutting face, the shape of the gullet, and the relationship between teeth all affect cutting efficiency, chip formation, and finish quality. Understanding these patterns helps you select blades that cut cleaner, faster, and with less effort.
ATB — Alternate Top Bevel
What It Looks Like
ATB teeth alternate between left-hand and right-hand bevel angles (typically 10-15°). One tooth angles left, the next angles right, creating a shearing action that slices through wood fibers cleanly.
How It Cuts
The alternating bevels create a slicing or shearing action, much like a pair of scissors. Each tooth scores the material from one side, then the opposing tooth scores from the other side, producing a clean cut with minimal tear-out.
Best Applications
- Crosscutting wood: Clean cuts across the grain
- Plywood and veneer: Prevents splintering of surface layers
- General woodworking: The most versatile geometry
- Finish carpentry: Smooth cut surfaces
Limitations
- Not ideal for ripping thick hardwood (can overheat)
- Struggles with very hard materials (metal, hard plastics)
- Teeth can chip when hitting nails or foreign objects
TCG — Triple Chip Grind
What It Looks Like
TCG teeth alternate between a flat-top raker tooth and a trapezoidal (beveled) tooth. The sequence is: trapezoidal tooth, flat raker, trapezoidal tooth, flat raker. The flat raker cleans out the bottom of the kerf.
How It Cuts
The trapezoidal tooth scores the material from the sides, then the flat raker scoops out the center. This combination provides both cutting action and chip removal, with the flat raker handling the bulk of material removal.
Best Applications
- Hardwood ripping: Fast material removal with good chip clearance
- Laminate and melamine: Chip-resistant cutting
- Non-ferrous metals: Aluminum, brass, copper
- Plastics and composites: Clean cutting without melting
- Nail-embedded wood: More resistant to tooth damage
Advantages
- Durable tooth design resists damage from foreign objects
- Excellent chip clearance for thick materials
- Versatile across wood, metal, and plastic
- Less prone to overheating on long cuts
FTG — Flat Top Grind
What It Looks Like
FTG teeth have flat tops with no bevel. All teeth are identical, with square cutting edges that chop through material like a series of chisels.
How It Cuts
FTG teeth cut with a chipping or planing action. Each tooth removes a chip of material equal to the feed per tooth. The flat top produces a flat-bottomed kerf — essential for certain joinery applications.
Best Applications
- Ripping softwood: Fast, aggressive material removal
- Grooving and dado cuts: Flat-bottomed kerf required
- Rabbet cuts: Flat bottom essential
- Production ripping: Maximum feed rate
Limitations
- Produces rougher cuts than ATB
- Significant tear-out on crosscuts
- Not suitable for finish-quality work
Geometry Comparison Summary
| Feature | ATB | TCG | FTG |
|---|---|---|---|
| Cutting action | Shearing/slicing | Scoring + raking | Chipping/planing |
| Finish quality | Excellent | Good | Rough |
| Chip clearance | Moderate | Excellent | Good |
| Cut speed | Moderate | Fast | Fastest |
| Best operation | Crosscut | Rip + general | Rip only |
| Metal cutting | Poor | Good | Poor |
Combination Tooth Geometries
Some blades combine geometries for versatile performance:
- ATB + Raker: Alternating ATB teeth with periodic flat raker teeth for improved chip clearance
- Hi-ATB: Higher bevel angles (20°+) for ultra-clean crosscuts in veneer and laminate
- Modified TCG: Variations for specific materials like aluminum or solid surface
Conclusion: Geometry Determines Cutting Action
Choose ATB for clean crosscuts and finish work, TCG for versatile ripping and general-purpose cutting including metals, and FTG for maximum-speed ripping where cut quality is secondary.
At JKINGS Tools, our TCT saw blades are available in ATB, TCG, and FTG tooth configurations, optimized for specific materials and cutting operations. Contact us for tooth geometry recommendations.
