How to Choose the Right Rock Breaker Chisel for Your Application

Hydraulic rock breakers are only as effective as the chisel doing the work. Fitting the wrong tip geometry to the wrong material wastes hydraulic energy, accelerates wear, and in the worst case damages the breaker's piston and bushings from repeated off-axis impact. ## Blunt Tip — General Demolition & Hard Rock A flat, blunt-nosed chisel spreads impact force over a wider contact area, making it the default choice for breaking hard, dense rock and general demolition work where the material doesn't have a natural fracture line to exploit. Blunt tips also tend to last longer in abrasive rock since there's less concentrated wear at the point. ## Mole Tip — Concrete & Secondary Breaking The mole (or "moil") point concentrates force into a smaller contact area, punching through concrete and rock more aggressively per blow. It's the standard choice for secondary breaking — reducing already-fractured material into manageable pieces — and for boring through reinforced concrete where a blunt tip would just skate across the surface. ## Wedge Tip — Directional Breaking Along Seams A wedge (chisel-edge) tip concentrates force along a line rather than a point, ideal for rock or concrete with a visible seam, joint, or bedding plane you want to exploit. It's also useful for trenching and directional breaking where you need control over the fracture line rather than just raw impact. ## Matching Chisel to Machine Chisel shank diameter must match your breaker model exactly — using an undersized shank increases bushing wear and risks chisel breakage, while an oversized shank simply won't fit. Our [rock breaker parts range](/categories/rock-breaker-parts) covers HM360, HM360HD, HM380 and HM390 chisel sets in Blunt, Mole and Wedge configurations, along with matching bush sets and pistons for the full HM series. ## A Quick Rule of Thumb If you're unsure which tip to run: start with Blunt for general hard rock, switch to Mole for concrete and secondary breaking, and reach for Wedge only when there's a seam or joint to exploit. Carrying one of each on-site covers the vast majority of demolition and quarry conditions.