Diamond Blade Troubleshooting
Very few diamond blade problems are caused by warranty failures - less than .001%
We have created a "Problem-Solving" guide to help you identify, diagnose and correct problems with diamond blades. The following are samples of problems you may encounter with diamond blades in the field. We have developed a cause-and-remedy guide to diagnose and correct these problems.
Most common diamond blade problems come from:
- Using the wrong blade for the job
- Using the blade improperly
- Equipment problems
Loss of Tension
Cause: Blade being used on a misaligned saw.
Remedy: Check for proper saw alignment.
Cause: The blade is excessively hard for the material being cut, creating stress on the steel center.
Remedy: Make certain the blade is correct for the material being cut (consult the manufacturer's recommendation chart or see your dealer).
Cause: Material slippage causes the blade to twist and become kinked or bent.
Remedy: Maintain a tight grip on the material while sawing.
Cause: Using blade flanges that are undersized or not the same diameter, creates uneven pressure on the center.
Remedy: Make certain blade flanges are of proper size and identical diameter, minimum 3-7/8"; 4-1/2" on concrete saws: 6" minimum on diamond blades that are 30" diameter and larger.
Cause: Blade being used at improper RPM.
Remedy: Make certain the blade shaft is turning at the proper RPM by using a tachometer. This is especially important with concrete saws.
Cause: Blade improperly mounted on arbor shoulder becomes bent when flanges are tightened.
Remedy: Hold the blade securely on the arbor shoulder until the outside flange and nut are firmly tightened.
Cause: Undercutting is a condition in which the steel center wears faster than the diamond segment, especially in the areas where the segment and core are joined. The condition is caused by highly abrasive material grinding against the blade during the sawing operation. Usually, materials containing sand are responsible for this condition. (See section on Segment Loss).
Remedy: The flow of swarf (abrasive cuttings) must be distributed over a wider area, away from the critical segment area. Many times this can be accomplished by using polyarc segments or other types of undercut protectors specially positioned around the steel center to change the pattern of constant abrasion. Although successful in most cases, undercut protectors do not provide 100% protection.
Uneven Segment Wear
Cause: Segments worn on one side reducing side clearance; usually caused by misalignment of the saw or a lack of sufficient water on both sides of the blade.
Remedy: Check saw alignment. Clean water system; make certain that water is properly applied to the leading edge of the blade flanges. Check to see if the pump is supplying sufficient even water. (See Rapid Wear Section).
Cause: Blade is worn out-of-round due to bad bearings, worn arbor, or excessive dulling condition. (See section on Excessive Wear).
Remedy: Replace bearings or worn arbor as required.
Cause: Using the wrong blade on highly abrasive material (Example: glazed tile blade on the concrete block).
Remedy: Consult the dealer or manufacturer for the proper blade specification for abrasive material.
Cause: Lack of sufficient coolant to the blade; often detected by excessive wear in the center of the segment. (Note: In both above cases, diamonds will usually be highly exposed).
Remedy: Clean up the water system. Make certain the water pump is functioning properly.
Cause: Wearing out-of-round accelerates wear. Usually can be caused by bad bearings, a worn shaft, or using a blade too hard for the materials being cut.
Remedy: Check bearings and arbor. If worn, replace it with new parts before installing another blade.
Cause: Insufficient power caused by loose V-belts, inadequate voltage, or improper RPMs.
Remedy: Tighten belts (taut). Replace worn belts. Check voltage. Use the proper extension cord.
Cause: Blade is too hard for material being cut.
Remedy: Use the correct blade with a softer bond.
Cause: Excessive cutting pressure, jamming, or twisting the blade in the cut can cause the blade core to bend or flex. When subjected to extreme stress and metal fatigue, the blade's steel core will eventually crack.
Remedy: The saw operator should use steady, even infeed pressure, and be careful not to twist or jam the blade in the cut.
Cause: Overheating through the inadequate water supply or improper use of dry-cutting blades.
Remedy: Use adequate water to cool wet-cutting diamond blades (for example, 2 - 5 gallons per minute for concrete saws). Allow adequate airflow around dry-cutting diamond blades to prevent overheating.
NEVER USE A BLADE WITH A CRACKED CORE!
Cause: The material slips during cutting, which twists or jams the segments loose.
Remedy: Hold the material securely while cutting.
Cause: The blade is too hard for the material it is cutting, causing excessive dullness, which causes the segment to pound off or fatigue.
Remedy: Use a softer blade specification.
Cause: Worn blade flanges fail to provide proper support causing the blade to deflect.
Remedy: Replace both blade flanges.
Cause: Out-of-round blade rotation resulting in pounding caused by worn arbor or bad bearings in the shaft.
Remedy: Replace worn arbor and/or bearings.
Cause: Overheating. Usually easily detected by bluish color on steel center, generally confined to the area where the segment was lost.
Remedy: Check the water system for blocked water passages. Test the pump to see if it is functioning. For dry cutting, it may be necessary to make shallower cuts and allow the blade to run free every few minutes to let the air cool it.
Cause: The bond is too hard for the material being cut. The hard bond retains the diamonds, and they begin to round off, causing the blade to become dull. Instead of cutting, the blade begins to "pound", causing the blade to wear out-of-round.
Remedy: Change to a softer bond, which will wear away more readily allowing the dull diamonds to be released and sharp, new cutting edges to become exposed.
Cause: The saw blade shaft may have a groove scored in it, caused by a blade spinning between the flanges. A new blade, installed on the arbor shaft, will seat into the groove, and immediately run eccentrically when the saw starts.
Remedy: Replace the worn shaft.
Cause: If the blade shaft bearings are worn, the shaft and mandrel will run eccentrically, causing the blade to wear out-of-round. This happens most often with concrete saws when proper lubrication of the bearings is neglected.
Remedy: Install new blade shaft bearings. In some cases, it might also be necessary to replace the blade shaft if it is worn out of alignment.
Cause: Adequate coolant was not provided.
Remedy: Check the water supply for adequate volume and for obstructions through the water system. Use dry blades ONLY for shallow cutting (1 - 2" deep) or step cutting. Allow the blade to run free every 10 to 15 seconds to increase cooling airflow.
Arbor Hole out of Round
Cause: The saw arbor is worn due to the blade being improperly seated.
Remedy: Be certain the blade is properly seated on the arbor before tightening the flange.
Cause: Blade flanges not properly tightened permitting the blade to rotate on the shaft.
Remedy: Always use hex nuts. Never use wing nuts.
Cause: Blade flanges or arbor shaft worn and not providing proper blade support.
Remedy: Check blade flanges or arbor shaft for wear. Both flanges should be no less than that recommended by the manufacturer. Replace worn parts.
The blade won't Cut
Cause: Blade is too hard for materials being cut (examples: block or general purpose blade being used for an extended period on hard brick; asphalt blade being used to cut hard concrete).
Remedy: Consult the dealer or manufacturer for the proper blade to cut materials on the job.
Cause: Insufficient power to permit the blade to cut properly (loose V-belts, low voltage, motor lacks horsepower).
Remedy: Check belts, voltage, and horsepower.
Cause: Blade has become dull because of continuous use on fairly hard or vitrified material.
Remedy: Dress with abrasive material until diamonds become exposed again (this may be necessary occasionally but if dullness occurs too often, the blade is probably too hard for the material).
Cause: Blade segments appear to still have plenty of life but the blade won't cut.
Remedy: Some harder-bonded blades designed for abrasive materials require a non-diamond bearing section at the base of the diamond segment for better adherence to the steel core. A blade used to this stage has worn out in the normal manner and should be replaced.