Thanks so much for all the info. I am a beginner. My blades (nearly all Olson) always break in the same place, near the top. I've been using a Jet saw with different thicknesses of wood. I was told that after I've clamped the blade and am adjusting the tension, I should be able to make the blade 'ping' by 'strumming' it. I always do this, and they still break.
I was cutting thinner composite board, but recently started cutting pine, 2cm thick, with 10tpi blades. I go really slowly, cutting at about 1mm every couple of seconds (!), but the blades still break.
Thanks in advance for all the marvellous tips!