Many workshop operators overlook blade break in and run brand new bimetallic blades at full feed and speed right away, which ranks among the top causes of early tooth chipping and shortened service life. Freshly ground saw teeth feature sharp, delicate tips that cannot withstand heavy instantaneous impact. Without proper running‑in, micro‑cracks easily form on cutting edges, leading to unstable cuts and frequent unexpected failures on the production floor.
Standard break in practice requires reducing feed pressure to roughly 50 % of normal operating value while keeping band speed unchanged for the first 15‑30 square centimetres of cutting area. This gradual process polishes tooth tips gently and builds stable chip forming conditions, without harming original tooth geometry including rake and clearance angles. Operators should watch for vibration, squealing noise or abnormal chip shapes as warning signs. If these symptoms appear, lower feed rate further rather than adjusting tooth parameters.
Break in rules apply equally to M51 and other high‑grade bi‑metal grades. Even premium quality saw blades cannot skip this step. After completing the break in phase, you may restore standard cutting parameters. Many reported blade life complaints actually stem from missing this simple procedure, instead of defects on the blade itself. Correct break‑in delivers far more visible gains than arbitrarily modifying tooth angles.
