(06-20-2022, 03:06 PM)Bob Vaughan Wrote: Old blades may or may not be worth sharpening. The key question about resharpening is the flatness of the plate. The fist time a sliver bangs between the throat plate and the blade may mean that there is a permanent bend in the blade. Checking straightness of the blade's plate in your saw would be a good exercise to prevent you from paying to have a bent blade sharpened.
Your comment about flatness of the blade peaked my curiosity. I had to check it out. I set up my dial indicator on my unisaw and checked six 10" blades. I cleaned each blade with CMT blade and bit cleaner before checking. In each case, I got as close to the teeth as possible, without getting into any laser cuts. On the Freud blade, this wasn't very close. I checked a Milwaukee 24 tooth. A Freud 24 tooth. A Bosch 24 tooth. (it came with the saw when I bought it). A CMT 24 tooth. 2 CMT 40 tooth. Bear in mind this is not a $500 Starrett dial indicator, but I have rebuilt a lot of small engines using it, and I trust it. The numbers represent in thousandths of an inch, how much side to side wobble (if you will) there is in each blade.
Milwaukee 24 tooth......7 Thin kerf
Freud 24 tooth.............3 Thin kerf
Bosch 34 tooth.............4 Thin kerf
CMT 24 tooth...............3
CMT 40 tooth...............4
CMT 40 tooth...............3
Th4 CMT blades are at least 25 years old. All other blades are relatively new. I have more 40 tooth blades but they are in the sharpening shop. I have never really liked the Milwaukee blades. They always seem to me, to chatter more than other blades, but it's what my local store sells, so I have bought several, and they are thin kerf, which I also don't like. I like something with some meat to it. I also took my dial indicator and checked the 12" Milwaukee, 100 tooth blade on my miter saw. 8 thousandths.
I was visiting a long time wood worker a while back. He was showing me on his table saw how the belts had " memory" to them. Ha hasn't done any woodworking in a long time. He would turn the blade by hand, and the blade would naturally spi9n back to where it was. He called this "memory" in the belts, and claimed it could cause more saw marks in your cuts. I am sure my unisaw belts are original to the saw, and also have memory. Anything to this do you think?
Thanks Greg
Sometimes it's better to keep your mouth shut, and have the world think you a fool, than to speak and remove all doubt.