Printed from Kezuriba (kezuriba.net/en/maintenance/bandsaw/troubles/)

Band saw troubleshooting quick reference

Look up likely causes, what to check, and remedies from the symptom. The values for tension, saw speed, feed, and break-in are guidelines published by blade makers and vary with blade type, maker, and material. The operation manual of your machine and the blade maker's recommendations come first. Band saws for woodworking are out of scope (the legal provisions also differ)

Cuts crooked (cut runs off line, cut surface is slanted)Common

Likely cause	What to check	Action
Blade tension is too low	Measure the tension with a tension gauge	Tension to the specified range (see the table in the Blade Care section). WIKUS recommends 250–300 N/mm²^[1][2][3]
Side guide clearance is too large, or side rollers or inserts are worn	Guide clearance, wear and looseness of rollers and inserts	Set mechanical guides to 0.02–0.05 mm (WIKUS). Replace worn rollers and inserts (OSG). Readjust the guide arms after mounting a new blade (Starrett)^[1][3][2]
Guide arm spacing is too wide	Gap between the guide arms and the material	Bring the guide arms as close to the material as possibleStarrett says to use the upper part of the tension range when the guide arm spacing is wide^[1][3](1 source, for reference)
Feed (descent speed) is too high	Feed scale, descent speed	Reduce the feed (match the blade maker's recommended value)^[1][3](1 source, for reference)
The blade is worn and has lost sharpness	Rounding of the tooth tips, longer cutting time	Replace the bladeDoALL lists cuts that are no longer square and longer cutting time as signs of lost sharpness^[1][4]
Material is not clamped firmly (especially when cutting bundles)	Vise clamping, movement of bundled material	Clamp the material firmly. For bundles of round bar, use a bundle clamp (Starrett)^[3][2]
Uneven tooth set (the chip brush is damaging the teeth on one side, or poor set)	Difference in wear between left and right of the teeth, brush contact	Readjust or replace the brush. Replace a blade with damaged set^[1][3](1 source, for reference)
The weld is not straight (a blade welded by yourself on a contour machine)	Bend in the weld	Redo the weld, or use a pre-welded blade^[5](1 source, for reference)

Blade dulls quickly (fast wear)Common

Likely cause	What to check	Action
Saw speed is too high	Saw speed relative to the material	Lower the saw speed to the blade maker's recommended value. When cutting a variety of materials, set it for the hardest material (DoALL)^[1][4][6]
Too little cutting fluid, poor aim, or wrong concentration	Nozzle direction, flow rate, concentration (refractometer)	Re-aim the nozzle at the teeth and adjust the amount and concentration^[1][4][2]
The blade was not broken in	Check whether a new blade was used at full load from the start	Break in the next blade (see the Blade Care section)^[1][4][7]
Sand or scale is on the material surface, or there are hard inclusions	Material surface	Review the conditions and blade type. If necessary, clean or grind the surface of the part to be cut^[1](1 source, for reference)
The feed is too low, so the teeth do not bite, rub instead, and work-harden the material	Whether chips are coming off and whether there are rubbing marks	Increase the feed force. If the blade has already lost sharpness, replace it^[2](1 source, for reference)
Blade not suited to the material (blade material, pitch)	Material, size, and blade specification	Choose a blade that suits the material. If wear is fast, change to a blade of a higher-grade material (OSG)^[4][8][2]

Teeth chip or stripCommon

Likely cause	What to check	Action
Feed (descent speed) is too high	Feed scale, descent speed	Reduce the feed^[1][9][2]
Saw speed is too low (the teeth dig in too deeply)	Saw speed relative to the material	Raise the saw speed to the recommended value^[1][2]
Pitch does not match the cross section of the material	Thickness being cut and the pitch	Reselect the pitch (see the table in the Blade Care section)OSG also says to change the pitch or descent speed when the teeth hit a corner at the start of a cut on square stock, and when the cutting length suddenly increases at the end of a cut on square stock or square pipe. Starrett says a wrong pitch packs chips into the gullets and strips teeth^[1][9][2]
Material is not clamped firmly enough (it moves in the vise)	Vise clamping, dirt on the vise face, hydraulic pressure	Clamp the material firmly. OSG lists cleaning the vise surface, checking the hydraulic pressure, and changing the hydraulic fluidStarrett says cracks on the back side of a tooth are a sign that the material is moving in the vise^[1][9][2]
Chips welded to the teeth (too little cutting fluid, bad chip brush)	Chips in the gullets, brush wear and position, cutting fluid	Adjust or replace the brush. Increase the cutting fluid and aim the nozzle^[1][9][2]
Break-in was not enough	Whether the new blade was broken in	Break in the blade thoroughly^[9][2]
Fragments of teeth from the previous blade remain in the kerf	Whether a new blade was put into the same kerf after teeth were stripped	Start the cut at a new position, or turn the material over and cut from the other side^[2](1 source, for reference)
The blade runs out vertically (uneven wear of the idler drum, loose guide arm)	Drum wear, guide arm fixing, blade alignment	Tighten what is loose and set the blade alignment. Have worn parts repaired by servicing^[9](1 source, for reference)

Blade breaks (body breakage, weld breakage)Common

Likely cause	What to check	Action
Tension is too high	Measure the tension with a tension gauge	Lower the tension to the specified range (250–300 N/mm² for WIKUS)^[1][10][11]
Guide position is off, guide rollers are too tight, or guides are worn	Alignment of the guides and wheels, play and tightness of the rollers, looseness and tilt of the inserts	Readjust the guides and replace worn ones^[1][10][2]
Back-up guide (back roller) is worn or presses too hard	Cracks in the blade back, grooves and cracks in the back-up guide	Replace or readjust the back-up guide. OSG gives 0.3 mm of wear as the limit for replacement^[2][10]
The blade back is hitting the wheel flange	Gap between the blade back and the flange	Readjust the blade tracking with the wheels and guides^[1][2]
Scratches on the wheel surface, tapered wear, bad bearings, runout	Wheel surface, bearing play	Repair or replace the wheel. Adjust or replace the bearings for play^[1](1 source, for reference)
The blade sits too deep in the guides	Whether the teeth and gullets stick out past the guides	Set it so that all of the teeth and 1–2 mm of the gullet stick out past the guides^[1](1 source, for reference)
Descent speed is too high	Feed scale	Set a proper descent speedOSG says to take particular care with hydraulic feed in winter^[10](1 source, for reference)
Fatigue (straight break)	Whether the break surface is straight	Replace the blade as end of life. Review tension, wheel diameter, and guide condition^[2](1 source, for reference)
Bad weld (breaks at the weld)	Whether the blade broke straight across the weld or at an angle	WIKUS says not to discard a blade that broke at the weld but to reweld it, and to inspect for hidden faults in the guides and wheelsOSG says that if the blade wore normally and broke straight across the weld, suspect material selection; if it did not wear, suspect tension, roller wear, or pitch; and if it broke at an angle, suspect pitch too coarse, descent speed, or machine vibration^[12][1](1 source, for reference)

Cut surface is wavy or roughCommon

Likely cause	What to check	Action
Saw speed is too low, or feed is too fast and chips pack into the teeth	Saw speed and feed	Match the saw speed and feed to the recommended values^[2](1 source, for reference)
Not enough support for the blade (loose guide arm, too little tension)	Guide arm fixing and tension	Set and tighten the guide arms and bring the tension to the specified value^[2](1 source, for reference)
Tooth damage or wear	Chipped or worn teeth	Replace the blade^[2][4]

Chatter, vibration, noiseCommon

Likely cause	What to check	Action
A new blade has not worn in	Whether the blade is new	Lower the saw speed until the vibration noise stops, and break the blade in^[13](1 source, for reference)
Saw speed is too high	Saw speed relative to the material	Reduce to a proper saw speed^[8](1 source, for reference)
Pitch is too coarse or does not match	Thickness being cut and the pitch	Use a finer pitch, or switch to a variable pitch bladeWIKUS says variable pitch reduces vibration. DoALL says a wrong pitch increases vibration^[8][14][4]
Blade wear	Tooth wear	Replace the blade. If wear is fast, change to a higher-grade blade^[8][4]

Causes on the side of machining conditions and tools are covered in the Machining Troubleshooting Encyclopedia .

📚Sources

Items without a mark are those on which two or more materials from different publishers agree. Values and intervals are governed by each machine's specifications. The text is summarized in Kezuriba's own words.