Diamond Core Bit Troubleshooting

Powsan has prepared this guide to help you find, identify and resolve the problems which you may encounter with diamond core bit.

The diamond core bit will not cut	CAUSE		REMEDY
	The bit is not of the right diamond specification for the material to be cut.		Fit the bit of correct diamond specification.
	Diamond segments have become ‘glazed’.		Re-sharpen the tool by drilling into abrasive material (sandstone, block etc.)
	Excessive speed of rotation.		Adjust speed of rotation.
	Excessive coolant, causing the bit to slide or aquaplane.		Reduce the water flow.
	Excessive play in the spindle or carriage guides.		Ensure a snug fit between spindle and drill. Tighten carriage guides.
	Insufficient downward weight or pressure on the drill.		Increase downward pressure and apply this evenly.
	The machine is badly fixed.		Check that the machine’s fixing is correct.
	The motor is too weak.		Match the motor power to the diameter.

Excessive wear of diamond segments	CAUSE		REMEDY
	Cooling system is not working adequately.		Overhaul cooling system and adjust flow to correct levels.
	Insufficient speed of rotation.		Increase speed of rotation.
	Excessive speed of advance.		Reduce speed of advance.
	The material is more abrasive than expected.		Use a bit with a harder diamond specification.
	Too much motor power applied to the bit.		Match the motor power to the bit.
	Instability of the machine or excessive play in the spindle or carriage guides.		Ensure machine is firmly anchored and stable. Ensure a snug fit between spindle and drill. Tighten carriage guides.

The bit jammed in the hole	CAUSE		REMEDY
	Debris (steel, pieces of material, a segment which has broken off) has filled the drilling hole. *A steel bar has been drilled “banana shaped”; it has moved during drilling and jammed the bit (wedge effect).		Disconnect the bit from the machine: use a spanner to turn the bit in both directions until it is released. Ensure adequate irrigation of the drill hole and flush out completely before recommencing drilling
	Loss of side-clearance of segments.		Check the side-clearance of the segments. If the play is too little replace the bit.

Segments broken and lost	CAUSE		REMEDY
	Excessive heat due to insufficient cooling.		Ensure that the water flow provides the correct level of cooling for the operating speed.  Repair or replace segments.
	The bit has suffered some knocks in the hole (due to steel or loose debris, etc.) and these have broken the segments.		Flush the drill hole clear of debris and increase water flow to ensure that problem does not recur. Remember that broken segments may form part of the debris and ensure that these are accounted for and removed, as otherwise these may cause substantial damage. Repair or replace segments.
	Excessive speed of rotation causes heating up of the segments.		Take the tool out of service, replace or repair it if possible. Adjust the speed of rotation.
	Start up too brutal.		Always start drilling gently.
	The bit has been dropped or damaged in transit.		Avoid dropping the bit on the ground as this can crack the segments.

Machine and motor problems	CAUSE		REMEDY
	Motor is underpowered.		Replace with a motor of the correct power.
	Machine is unstable or positioned at an angle.		Ensure machine is firmly anchored and stable.
	Cooling system problems.		Overhaul the cooling system, ensuring correct and even flow for the work being undertaken.
	Drill Motor is not properly fitted to the machine, causing excessive vibration. (e.g. Carriage guides and spindle fitting are too loose)		Check all the moving parts on the machine, especially spindle, bearings, rollers and carriage guides.  Ensure that parts are centred and operating freely but without excessive play.

Others	CAUSE		REMEDY
	The machine is badly anchored.		Anchor the machine firmly.
	The machine is incorrectly adjusted (excessive play in the carriage guides, motor spindle or adapter out of true, etc.).		Correctly adjust the machine, replace worn parts, correct the play (rollers, bearings, adapters, etc.).
	The bit is warped.		Repair any warped or damaged parts. Ensure that Core Drill is running true before continuing.
	The bit is not correctly fixed to the motor spindle.		Check that the bit is correctly aligned on the motor spindle (straight line).
	There are fragments of metal in the bottom of the hole that have not been evacuated by the coolant.		Remove all the metal fragments from the drilled hole. Temporarily increase the flow of water to clean out the hole and remove any debris that may still be there.