The bandsaw feed mechanism aids in proper machine usage, allowing for an easy and productive cutting procedure with positive end results. Blade life preservation is another aspect.
Gravity feed saws behave as their name implies and rely on their own weight. The cutting force can be adjusted by a movable counterbalancing weight, a screw-thread coil spring adjustment, or by a hydraulic or pneumatic damper or speed control valve. A damper won’t force the blade down but instead limits the fall speed, preventing excessive feed on thin or soft parts.
Hydraulic feed saws use a positive pressure hydraulic piston to move the band through the material at variable pressure and rate.
Metal cutting bandsaw machines come in vertical and horizontal models, and bandsaw feed will depend on these two variables.
Horizontal feed applies pressure to the material being cut, and with vertical machines it is the opposite: pressure is applied to the blade by the material being cut.
The feed rate for horizontal bandsaws is controlled with the adjustment of the pressure being applied by the blade against the material being cut. The use of a spring counterbalance and a sliding weight will adjust blade pressure, reducing it as the sliding weight moves toward the pivot point of the saw frame. Increased pressure is applied as the weight moves away from the pivot point.
When regulating the feed of horizontal band saw machines, the feed should be light at the start of a cut. After, feed is then increased. Wider materials require heavier feed and lighter feed for narrow materials.
Greater pressure is withstood using a wide blade and can be used with heavier feeds better than a narrower blade. Hard materials require a lighter feed; soft materials, a heavier feed.
Noticing hard spots on materials and in weld joints signals the need for a reduction in feed.
When using a vertical bandsaw, the material being cut applies feed pressure to the blade: hand or power fed depending on the procedure. Hand feed is required when special contour or curve cutting is performed.
Adjustable weights in the machine pedestal operate power feed on the bandsaw. Cable weights connected to the work-holding attachment pull the material against the blade. In operation, the weights rise by depressing a pedal, and the cables are affixed to the work-holding attachment. Releasing the pedal pulls the piece into the blade.
- The feed should be light at cut start — increasing pressure once cut has begun
- Light feed for hard material and harder feed for soft materials
- Wider blades withstand greater pressure and can take a heavier feed than a narrow blade
- Encountering hard spots in the material being cut means feed reduction is required
- Curve and contour cutting use a light feed and straight cuts use a heavier feed
Knowing the significance of the various bandsaw feed mechanisms will impact the cutting operation. The operator should possess adequate knowledge of feed regulation rule basics if accuracy, speed, and quality output are desired.