Problems - wide sawmill band-saws
Cracking in a saw’s gullet
| possible causes | suggested solutions |
|---|---|
| sharpening the part of the tooth’s profile | sharpen the whole tooth’s profile |
| burn marks in the saw’s gullets after sharpening, deep scratches on the saw left after sharpening |
match the abrasive disk, adapt the profile of the abrasive disk, use cooling and required feed during sharpening |
| dull blade | stop working, sharpen the saw |
| the gullet rounding radius too small | sharpen the saw increasing the radius |
| saw overheated – continuous work with no rest | adhere to the recommendations given |
| incorrect saw’s strain | set the strain according to the machine technical spec. |
| the cutting edges went in contact with the material before the proper operating speed was achieved | start cutting no sooner than the proper operating speed is achieved, according to the machine technical spec. |
| leaving the saw strained after work | always loosen the strain after work |
| irregular back of the saw | correct by adjusting |
| incorrect setting (too small, too big, asymmetrical) | correct the setting |
| overworked surface of the guide pulleys | grind the surface of the guide pulleys regularly |
| irregularities of the guide pulleys’ surface | grind the guide pulleys |
| sawdust and chips between the saw and the guide pulleys | keep the working surface of the guide pulleys clean |
Irregular cut
| possible causes | suggested solutions |
|---|---|
| incorrect saw’s strain | set the strain according to the machine technical spec. |
| the guide pulleys in poor condition, not set in one line | regulate the guide pulleys, set them in one line |
| incorrect tool rake angle | correct the tool rake angle by sharpening |
| incorrect pitch chosen | choose the correct pitch |
| asymmetrical setting | correct the setting |
| asymmetrical swaging, stelliting | correct the swaging, the stelliting by grinding sides |
Saw wandering along guide pulleys
| possible causes | suggested solutions |
|---|---|
| incorrect amount of the crown | adjust the band saw again (according to the amount of the crown on the guide pulleys) |
| incorrect tool rake angle | correct the tool rake angle by sharpening |
| incorrect saw’s strain | set the strain according to the machine technical spec. |
| overworked surface of the guide pulleys | grind the surface of the guide pulleys regularly |
| irregularities of the guide pulleys’ surface | grind the guide pulleys |