I've been trying to scroll some 1/4" Hackberry using a #3MS blade on my Delta Q3. The #3 blade seems to be the perfect size for what I'm cutting, but I'm having a heck of a time with blades breaking. The first blade popped after about 3 minutes, but the second lasted more than 30 minutes before I changed it myself. The 3rd, 4th, and 5th popped either as soon as I turned the saw on, or just as the blade started to cut - and no, they were not installed up-side-down.
I contact the person I bought the blades from, and he said that if the blades were breaking close to the top or bottom, and they were, then I probably had the clamps on too tight. So last night, I loosened the clamps, but as soon as I tensioned the blade, it slipped out of the clamps - obviously I loosened them too much. So after some trial and error, I found the spot where the clamps were tight enough to hold the blade, and the blade didn't pop out of the clamps as soon as I got tension on the blade.
However, I haven't had any better luck with the blades not breaking, and I broke 3 more without getting any more cutting done. I've also tried not tensioning the blade as much as I would using a larger blade. So, for the time being until I can figure out why my #3's are breaking, I had to jump to a #5 ( after loosening the clamps a little bit ) which will work for most of what I'm cutting. But I would really like to use the #3's.
Has anyone had this problem before, or can someone point me to some guidelines for tensioning the blade? I'm assuming that my problem is more with tension than it is with clamping pressure.