I've just bought a set of stack dado cutters to use on my tablesaw (an old startrite model) The arbor wasn't long enough so i had also brought an arbor extension which screws on. Having run a test piece of ply through, on which the cut was perfect, i turned the saw off but as it gradually slowed down the teeth on the chippers seemed to tap each other (only very slightly). Should all the chippers 'stay put' on the arbor as they seem quite free to rotate? I can send a pic if anyone can help ?