I agree with Dave.
I use an 80 tooth thin kerf blade and it is fairly new and sharp. Some blades are marked for plywood and usually have a lot of teeth. I have seen as many as 100 tooth blades at Lowe's.
I also recommend a zero clearance insert on the saw. You can make your own insert with 1/2" plywood and if necessary glue shims to the back of it to get it level with the table. (or maybe sand the back if it is too thick)
I have heard of people using tape and scoring the wood as you have suggested but, I've never done it myself. It might help sometimes.
I generally follow Dave's recommendation of keeping the blade low. Just a 1/16" or so above the material. However, I have also read that if you are getting tearout on your wood to raise the blade up as high as it will go so that the teeth are cutting more straight down on the wood and not ripping right through it from the front edge. There is some thing to be said for that too. You might give that a try anyway.
The other thing that Dave brought up is that sometimes it is just the piece of ply that you are using. We get all kinds of plywood from all over the world and you never really know about the quality until you cut it. Generally speaking, the more plys, the better the wood works. However, I once bought a sheet of 3/4" birch (not baltic birch) that had 9 plys in it and after cutting found that it was full of voids and was basically JUNK!
Rog
