Running saw blades at the correct feed and speed rates is important if the goal is to achieve desirable output. There is an optimum balance between blade speed and feed rate for every saw blade and every material to be cut.
Proper adjustment of feed and speed rates will help to maximized blade life and assure a satisfactory cut.
Feed rate is determined by the bandsaw, material size and shape, guide spacing, cutting fluid, and tooth size and shape. The greater the blade speed, the greater the feed rate — up to the limits imposed by the above-mentioned production factors.
Bandsaw machines come with various speed controls: fixed, variable pulley, infinite variable, and electronic drive. Machine speed gauges monitor speed but are not always accurate. It is best to physically check and then regularly adjust blade speed.
To check speeds of up to 600 SFPM (Surface Feet Per Minute), use the band’s weld or mark it and then count the number of times it comes around in one minute. Multiply by the length of the band in feet and inches. So, a 12’ 6” blade came around 14 times in a minute, meaning 12.5 x 14 = 175 SFPM
Bandsaw machines also come equipped with various feed controls: cylinder bleed off, hydraulic feed, constant feed, and air over hydraulic feed.
Feed rate should be smooth and steady, not erratic. A few helpful recommendations to achieving proper feed rate include:
- Using a coarse tooth blade so that each tooth has adequate force
- Set guides close to the work, permitting relatively heavy feed pressure while maintaining blade control
- Carefully controlled feed rate prevents blade teeth from stripping
- Fast speed, light feed for softer materials — 300 SFPM is good
- Slower speed, heavier feed for harder materials — 100 SFPM is good
Overfeeding will cause the machine to chatter and vibrate, making for a noisy cut, and the chips or shavings generated by the blade will give clues to proper or improper feed rates.
- A free cut, curly chip indicates ideal feed pressure — optimum cutting time and prolonged blade life are assured
- Discolored chips indicate too heavy a feed pressure — stripped teeth or blade breakage are guaranteed along with premature wear-out due to overheating
- Fine, powdery chips indicate too light a feed — blade teeth will rub against the material surface but not cut
Proper speed and feed help to prevent unnecessary blade damage, reduce material waste, and assure ease-of-operation. Keep in mind, though, that rubber and some fibers — plastics containing abrasives — will damage saw blades regardless of the careful selection of speed and feed rates.
Take advantage of our Speed and Feed Rate Chart at Sawblade.com.