Possible causes:

1. Inadequate blade tension
2. Blade guide misadjusted
3. Poor blade tracking
4. Sap buildup on blade
5. Dull blade
6. Feed rate too fast

Solutions:

1. Tighten the blade (see page 38)
2. Correct guide block gap (see page 36)
3. Adjust blade alignment (see page 30)
4. Install a new blade and always use blade lubricant (see page 38)
5. Install a new blade (see page 38)
6. Slow down the feed rate