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TROUBLE
SHOOTING GUIDE |
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As with any manufacturer, saw blade companies maintain
strict production quality control standards in order to
provide the best possible product to their customers. Except
for weld breaks, most saw cutting problems are caused by a
combination of incorrect speeds and feeds, operational
proceedures or an improperly maintained saw.
• BREAK-IN PROCEDURE
• BAND TENSION
•
BAND SPEED
•
FEED RATE
•
TOOTH PITCH
• CUTTING FLUID
• CHIP BRUSH
•
GUIDES
•
BAND TRACKING
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BREAK-IN PROCEDURE
Break-in a new band according to manufacturer's
instructions, using the same material as will be cut. Minimum
break-in procedure would be to set band speed according to the
correct speed chart. Reduce feed pressure 1/2 or 1/3 of the
recommended rate. Cut square inches recommended by the
manufacturer of the blade. After break-in, gradually increase
feed pressure until ideal chip curl is reached.
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BAND TENSION
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BLADE TYPE |
RECOMMENDED TENSION
(PER SQUARE
INCH) |
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FLEX BACK CARBON
BANDSAW
BLADES |
15,000-20,000 PSI |
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HARD BACK CARBON
BANDSAW
BLADES |
20,000-25,000 PSI |
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BI-METAL
BANDSAW
BLADES |
25,000-35,000
PSI |
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BAND SPEED
(SFPM)
A correct band speed achieves a correct shear
angle producing an ideal chip and more efficient cutting.
If the band speed is too high, the shear angle
will also be too high, allowing the band to ride through the
material producing thin chips and wearing the edges of the
teeth.
If the band speed is lower than recommended, the
tooth tries to take chunks of material, causing stress on the
tooth, possible breakage or stalling in the workpiece.
Identify the material you are cutting, locate it
or a material close to the same characteristics on our band
speed chart and adjust speed accordingly - use
the high side of the range with a new band, reduce to the low
side as the band wears.
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FEED RATE
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MACHINABLITY RATING OF METAL BEING
CUT |
BLADE SPEEDS |
RECOMMENDED FEED
PRESSURES |
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MACHINES WITH SET
SPEEDS |
MACHINES WITH VARIABLE SPEEDS-
FPM |
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GROUP 1 - EASILY MACHINED |
FAST |
110-350 |
MEDIUM LIGHT |
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GROUP 2 - MODERATELY DIFFICULT TO
MACHINE |
MEDIUM |
80-150 |
MEDIUM |
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GROUP 3 - DIFFICULT TO
MACHINE |
SLOW |
50-110 |
MEDIUM HEAVY |
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GROUP 4 - EASILY MACHINED -
NONFERROUS |
FAST |
110-300 |
MEDIUM LIGHT |
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TOOTH PITCH
• A tooth pitch that is too fine for a
particular cross section will result in gullet loading, slower
cutting rates and greatly reduced band life.
•A tooth pitch that is too coarse for a
particular application can result in band breakage, stalling
in the work piece or tooth damage.
• In general, a tooth pitch slightly too coarse
for a particular cross section is preferable to a pitch that
is too fine, if adjustments to cutting parameters and approach
to the work piece are made.
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CUTTING FLUID
• Always measure and mix coolant according to
the instructions provided by the manufacturer. Degraded or
poorly mixed coolant can be totally ineffective.
• Prepare the coolant mixture by slowly pouring
the concentrate into the water while stirring the mixture
vigorously. Mix coolant in a separate container and then pour
it into the reservoir. Do not mix in the reservoir.
• When adding make-up coolant to the reservoir,
follow directions of the manufacturer. Mix in a separate
container before pouring into the reservoir.
• Adjust the coolant nozzle so that fluid
completely covers both sides of the band on the side entering
the work piece.
• Use an adequate flow of coolant. Full flow is
seldom too much coolant.
• Fluid should be running before running the
band. Let the saw run long enough to carry fluid into the work
area before starting the cut.
• Keep a properly mixed supply of replenishing
fluid on hand, never add "water only" to the reservoir.
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CHIP BRUSH
• Check the condition and adjustment of the chip
brush routinely. Work hardened chips, if carried into the kerf
by band gullets, may cause damage to the band set, tooth
stripping or a scoring effect on the cut surface.
• The chip brush, to be effective, must be
properly adjusted. The shaft should be parrallel with band
travel. The brush should clean all chips from the tooth
gullets without touching the bottom of the gullets.
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GUIDES
Guide arms are adjustable in order to expose the
saw band to as little upward stress as possible. Beam strength
is dramatically increased when the distance of band flex is
reduced to a minimum. Stress cracks in the band and probable
eventual breakage can be caused by allowing the band to flex
upward.
Always adjust guide arms as close to the work
piece as possible without interfering with the cut.
IMPROPERLY ADJUSTED GUIDE ARMS
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BAND TRACKING
The term tracking refers to
the act of positioning the blade on the bandsaw wheels so it
is in proper relation to the table, work piece, backup
bearings and saw guide inserts.
To position it properly,
tilt the top wheel (the angle of the top wheel steers the
blade in the direction of the tilt). Track the blade when it
is under full tension. When a blade is properly tracked, it
will run in a straight line.
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