A groove cutting machine is only half the equation. The blade decides how fast you cut, how clean the groove is, and how much each metre of cutting actually costs you. Fit the wrong blade and even a strong machine like our Honda 13HP GX390 cutter will crawl through the job.
Blade types in plain terms
Segmented rim diamond blades
The workhorse for road and floor cutting. The rim is divided into segments with gaps between them, which clear slurry and help the blade run cooler. This is the standard choice for cutting cured concrete grooves and expansion joints, and it tolerates dry cutting better than other rim types.
Turbo rim blades
A continuous rim with a serrated pattern. They cut faster than segmented blades in many materials and leave a cleaner edge, but they run hotter. Useful where cut appearance matters.
Continuous rim blades
Smooth, unbroken rim for the cleanest cuts, normally used wet. More common for tiles and finishes than for road work.
Abrasive blades
Cheap to buy but they wear down fast and lose diameter as they cut. For daily groove cutting work, a diamond blade costs less per metre of cut even though it costs more upfront.
Concrete blade or asphalt blade?
This is where many crews go wrong. Diamond blades hold their diamonds in a metal bond, and the bond hardness must match the material.
- Cured concrete is hard. It needs a softer bond that wears away steadily and keeps exposing fresh diamonds. Use a hard-bond blade on concrete and it glazes over and stops cutting.
- Asphalt is soft but abrasive. It needs a harder bond that resists the sandpaper effect. Asphalt blades often have undercut protection segments to stop the abrasive slurry eating into the steel core.
If your work mixes both, ask your blade supplier for a combination blade rated for concrete and asphalt. Tell them the material, and tell them your machine. Blade diameter and arbor size must match the cutter, whether that is our 5HP Greaves diesel machine starting around ₹55,000 or the VST Shakti 13HP diesel cutter.
Wet vs dry cutting
Wet cutting uses a water feed onto the blade. It keeps the blade cool, extends blade life, suppresses dust and usually allows deeper continuous cuts. Road cutting machines carry a water tank for exactly this reason. Where water is available, cut wet.
Dry cutting is for short cuts or sites with no water. Use a blade rated for dry cutting, cut in short passes, and let the blade spin free between passes to cool. Never dry-cut continuously with a wet-only blade. It overheats, and an overheated blade can warp or shed segments, which is dangerous at operating speed. Dry cutting also throws fine silica dust, so keep operators masked and bystanders clear.
When to replace a blade
Watch for these signs:
- Slow cutting despite good pressure. The blade may be glazed. Sometimes a few passes in a soft abrasive material re-exposes the diamonds. If not, it is done.
- Segments worn thin or worn flush with the core. No diamond left means no cutting left.
- Missing or cracked segments. Stop immediately. Do not keep running a damaged blade.
- Wobble or a visibly bent core. Replace the blade and check the machine arbor and flanges.
- Undercutting. A groove worn into the steel core just below the segments, common in asphalt. The segments can break away. Replace the blade.
Blade cost is a running cost, just like fuel. If you are still choosing the machine itself, our guide on diesel vs petrol concrete cutters compares engines and running costs. For blades, spares and machine advice, call HMS in Bengaluru. We have kept South Indian road contractors cutting since 1999.
