I have a 4 month old Jet Xacta Deluxe 3HP, Left Tilt cabinet saw. I had noticed some vibrations (by sound more than anything) after I installed my zero clearance insert. It sounded like the blade was rubbing on the insert but it only happened some of the time. I've realized today that when I raise the blade and spin it by hand (unplugged of course) the blade moves freely and doesn't touch the insert. However, if I lower the blade even a slight amount and try to spin the blade it will rub on the insert. I then raise it just a bit and the rubbing stops. Doesn't seem to matter what height or if I lock the mechanism down or not. This is happening with all my blades (FWWII, Oshlun 80 tooth and Delta Dado) - all rub on the left side. I tried checking it with my Wixey angle finder but its not sensitive enough. It only moving like .001 or so (no feeler gauges so thats a guess) but its enough for the rubbing to occur. Seems to be 100% repeatable.

Is this normal or is there something I need to adjust? Should I just always plan on setting my final blade height via raising the blade and never lowering?

Thanks

Steve