Reducing Cost per Meter Drilled: A Practical Guide for Quarry Managers

Bit selection and service life Up to 30% savings

The wrong bit for the rock type is the fastest way to inflate cost per meter. In soft to medium rock (Mohs 3–5), a chisel or cross bit cuts efficiently and economically. However, in harder formations — granite, quartzite, and basalt at Mohs 6–7 — only a button bit or ballistic bit with properly sized tungsten carbide inserts maintains penetration rate without excessive wear.

Specifically, the choice between a button bit and a ballistic bit matters: button bits distribute percussion energy through hemispherical carbide inserts, making them well suited to very hard, abrasive rock. Ballistic bits, by contrast, use conical inserts that penetrate softer formations more aggressively. Using a ballistic bit on granite, for instance, leads to rapid insert fracture and dramatically reduced metres-per-bit life.

Set Makina’s TIGER Button Bits, TIGER Ballistic Bits, and TIGER Chisel Bits cover the full hardness range. Moreover, matching the correct bit geometry to your specific rock type can extend bit life by 25 to 35% compared to using a general-purpose bit across all applications.

Bit regrinding and reconditioning 15–20% savings

Many quarry operations discard bits when they become dull — throwing away carbide inserts that still have significant usable life remaining. In reality, a structured regrinding programme extends bit life substantially. Most button bits support two to three regrind cycles before the insert geometry deteriorates beyond recovery.

Furthermore, a dedicated bit sharpening machine pays for itself quickly in high-volume operations. The TIGER GRINDER — Set Makina’s integral drill sharpening machine — restores worn insert geometry accurately and consistently, without the variability of manual grinding. In operations drilling more than 500 metres per week, regrinding typically reduces consumable spend by 15 to 20%.

Rod and coupling management 10–15% savings

Drill rods and couplings are often treated as secondary consumables — replaced when they break rather than managed proactively. However, worn rod threads and mismatched coupling tolerances create two problems that directly increase cost per meter. First, they reduce percussion energy transfer efficiency, slowing penetration rate. Second, they increase the risk of rod breakage downhole, which triggers costly fishing operations or lost-hole write-offs.

Consequently, a rod rotation programme — moving rods from the most-stressed position at the drill head down through the string as they wear — distributes fatigue evenly and extends total rod life by 20 to 30%. Additionally, inspecting coupling threads every 200 metres and replacing them at the first sign of thread flattening prevents the accelerating damage that a worn coupling causes to adjacent rods.

Set Makina supplies extension rods, MF rods, and shank adaptors alongside couplings compatible across the full TIGER drill range — simplifying inventory management and ensuring dimensional consistency throughout the string.

Lubrication discipline 40–60% reduction in drill failures

Inadequate lubrication is the leading cause of premature rock drill failure — and it is also the easiest problem to prevent. A pneumatic rock drill operates at 36 strikes per second at working pressure. Without a continuous oil film on the internal piston, valve, and chuck components, metal-to-metal contact rapidly scores the bore, reduces impact energy, and ultimately causes catastrophic internal failure.

In practice, the correct lubrication rate for most TIGER drills is 2 to 4 ml of drill oil per minute of operation. This requires a properly adjusted inline oiler — not a reservoir that operators fill occasionally and forget. The TIGER FY200B line oiler (200 ml capacity, available in plastic, aluminium, or steel body) provides continuous, flow-proportional lubrication directly in the air supply line. Moreover, its transparent plastic variant allows operators to confirm oil delivery visually without interrupting the drilling cycle.

Indeed, in most warranty claim investigations across the industry, lubrication failure is the root cause in the majority of premature drill damage cases. An operation that runs drills without an inline oiler typically reduces drill service life by 40 to 60% — making the oiler one of the highest-return accessories available.

Compressor efficiency and air pressure 15–25% energy savings

Compressed air is the energy carrier for every pneumatic drilling system, and compressor fuel or electricity typically represents 20 to 25% of total drilling cost. However, most quarry operations run their compressors at higher pressure than necessary — either from habit or because a poorly maintained drill requires more pressure to achieve adequate penetration.

Specifically, most TIGER pneumatic rock drills operate optimally at 5 to 6 bar. Running the compressor at 8 or 9 bar increases energy consumption proportionally while providing little additional benefit to penetration rate. In fact, above the design operating pressure, increased pressure often causes valve bounce and accelerated internal wear rather than improved performance.

Additionally, leaking hose connections are a major source of wasted energy that few operations quantify. A 3 mm leak in a fitting at 6 bar wastes approximately 30 litres per minute of compressed air — roughly half the consumption of a TIGER YT24 air-leg drill. Therefore, checking and replacing pneumatic fittings and hoses quarterly is one of the highest-return maintenance activities available.

Unplanned downtime and drill repair cycles Highest total impact

Of all six cost drivers, unplanned downtime carries the highest cost impact — not because repair costs are excessive, but because every hour a drill sits idle, the fixed costs of labour, equipment depreciation, and contract commitments continue to accumulate against zero metres drilled.

Furthermore, when an operation lacks spare drills or critical spare parts on site, a single drill failure can halt an entire production face for days. Consequently, the most cost-effective operations maintain a minimum inventory of high-wear parts — piston O-rings, chuck bushings, valve assemblies, and shank adaptors — alongside at least one standby drill per active face.

Set Makina ships critical spare parts within 24 hours from its Ankara facility to operations across 40+ countries. Additionally, all TIGER drill models share a significant proportion of common internal components across the range — meaning a single spare parts inventory covers multiple machine types and reduces the capital tied up in spare stock.