Saw blades which have been developed for particleboard will cut MDF with reasonable success, but the adoption of alternate top bevels of 15° and an increased tip clearance angle of 20°-22° will further extend the life of the saws between sharpenings, thereby reducing costly down time.
The following general recommendations based on research and experience gained over twenty years working with MDF will help to ensure smooth cut edges, minimal breakout and long saw life.
Thus a 400 mm diameter saw blade with a recommended rim (peripheral) speed of 60-70 m/s should be operated with a running speed in the range 2800 – 3300 RPM.F
Chipload which is the amount of material removed by each tooth should be in the range 0.15 to 0.25 mm. The feed speed required to produce this chipload is calculated as follows;
Feed speed (mm/min) = RPM x No. of teeth x chipload (mm).
When using a 40 tooth saw blade, irrespective of diameter, operating with a running speed of 3000 rpm, the feed speed should be in the range 18 m/min (0.15 mm chipload) to 30 m/min (0.25 mm chipload).
At low feed speeds, the saw crushes and abrades the MDF rather than cutting it and the frictional heat generated by pressure on the tips can seriously reduce saw life. At higher feed speeds, the quality of the cut edge will be diminished. The production of fine dust is a sure indication that the feed speed is too low whilst a ragged cut indicates too high a feed speed.
