Vacuum brazed diamond core drill bits are engineered for speed, clean cutting, and versatility across hard materials like granite, marble, porcelain, and concrete. However, hard surfaces and high friction can quickly wear down even high-grade diamond grit if the bit isn't used correctly.
To help you get the maximum value and footage out of your BRSCHNITT vacuum brazed core bits, here are 5 field-tested tips to significantly extend their lifespan.
1. Control Your RPM and Avoid Overheating
High friction generates extreme heat, which breaks down the bond holding the diamond particles to the core bit body.
• Optimal Speed: Run your angle grinder or drill at the recommended RPM range (typically 2,000–6,000 RPM depending on the bit diameter). Avoid running at maximum speed on ultra-hard stones like granite.
• Heat Management: Excess heat causes diamond segments to glaze over or lose their cutting edge prematurely. Keep your speed steady and controlled to reduce heat build-up.
2. Master the "Angled Entry and Feathering" Technique
Starting a hole flat against a hard surface causes the bit to walk, vibrate, and chip the diamond rim before it even bites into the material.
• Start at a 45° Angle: Place the edge of the bit against the material at a 45-degree angle to create an initial crescent groove.
• Slowly Straighten: Once the groove is established, smoothly lift the tool upright to 90 degrees.
• Use a Feathering Motion: During drilling, apply a slight orbital or circular motion. This movement allows dust to escape, improves cooling airflow, and prevents binding.
3. Apply the Right Pressure (Let the Diamonds Do the Work)
Applying excessive down-force does not speed up drilling; it generates excessive heat and strips the diamond grit right off the steel core.
• Light to Moderate Pressure: Let the sharpness of the diamond grit cut through the material under its own weight and light manual guidance.
• Avoid Stalling: If the drill slows down dramatically or stalls, you are pressing too hard. Back off immediately to prevent segment stress.
4. Clear Dust and Cool the Bit Periodically
Accumulation of fine stone or tile dust creates friction and clogs the diamond matrix, leading to overheating and rapid wear.
• Intermittent Pauses: Pull the bit out of the hole every 5 to 10 seconds while it's spinning to allow air to clear out dust and cool the cutting edge.
• Use Water When Possible: Although vacuum brazed bits are designed for dry drilling, adding a small splash of water or using a wet sponge significantly reduces dust, keeps temperatures low, and extends bit life.
5. Clean and Store Your Bits Correctly
Proper post-job maintenance ensures your bits are ready for the next project without degraded performance.
• Remove Debris: Clean out core plugs and material residue from inside the hollow tube after every use.
• Dress the Bit: Check the diamond rim for glazing. If the bit starts cutting slowly, dress it by drilling a short hole into an abrasive material (like sandstone or concrete block) to expose fresh diamond grit.
• Store Dry: Store bits in a clean, dry place to prevent rust on the threaded connection and core body.
Maintenance Quick Reference Table
| Maintenance Factor | Best Practice | What to Avoid |
| Drilling Technique | Start at 45°, move in slight orbital motion | Flat starts and rigid vertical pressure |
| Pressure | Moderate, consistent pressure | Pushing down hard to force the cut |
| Cooling | Periodic air clears or wet cooling | Continuous dry cutting without pauses |
| Storage | Cleaned, core cleared, dry environment | Storing covered in damp slurry or dust |