Troubleshooting The J-7020/7040 Band Saws - Jet J-7020 Operating Instructions And Parts Manual

13.0 Troubleshooting the J-7020/7040 Band Saws

Symptom
Excessive blade
breakage
Premature blade
dulling
Bad cuts
(out-of-square)
Bad cuts (rough)
Blade is twisting
Possible Cause
Material loose in vise.
Incorrect speed or feed.
Teeth too coarse for material.
Incorrect blade tension.
Saw blade is in contact with
workpiece before the saw is started.
Blade rubs on the wheel flange.
Misaligned guides.
Cracking at weld.
Blade teeth too coarse.
Blade speed too high.
Inadequate feed pressure.
Hard spots in workpiece or scale
on/in workpiece.
Work hardening of material
(especially stainless steel).
Insufficient blade tension.
Operating saw without pressure on
workpiece.
Workpiece not square with blade.
Feed pressure too fast.
Guide bearings not adjusted
properly.
Inadequate blade tension.
Span between the two blade guides
too wide.
Dull blade.
Incorrect blade speed.
Blade guide assembly is loose.
Blade guide bearing assembly loose.
Blade tracks too far away from wheel
flanges.
Guide bearing worn.
Blade speed too high for feed
pressure.
Blade is too coarse.
Blade is binding in the cut.
Blade tension too high.
Correction
Clamp work securely.
Check machinist's handbook for
speed/feed appropriate for the material
being cut.
Check machinist's handbook for
recommended blade type.
Adjust blade tension to the point where the
blade just does not slip on the wheel.
Start the motor before placing the saw on
the workpiece.
Adjust blade tracking.
Adjust guides.
Longer annealing cycle.
Use a finer tooth blade.
Try a lower blade speed.
Decrease spring tension.
Increase feed pressure (hard spots).
Reduce speed, increase feed pressure
(scale).
Increase feed pressure by reducing spring
tension.
Increase tension to proper level.
Do not run blade at idle in/on material.
Adjust vise so it is square with the blade.
(Always clamp work tightly in vise.)
Decrease pressure.
Adjust guide bearing clearance to 0.001
inch (0.002 inch maximum).
Gradually increase blade tension.
Move blade guide bar closer to work.
Replace blade.
Check blade speed.
Tighten blade guide assembly.
Tighten blade guide bearing assembly.
Adjust blade tracking.
Replace worn bearing.
Reduce blade speed and feed pressure.
Replace with finer blade.
Decrease feed pressure.
Decrease tension on blade.
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