I tighten the blade at about 3/4 maximum on my DW 788 and I have my tension adjusted to where full pressure is hard to get. It all in The inter adjustment of the machine. find out where the blade pings at a high pitch by using your fingernail . and as Kevin ask what speed are you running, I very seldom run it above 5. and a blade usually last me 1-2 hours, i CAN TELL BY THE WAY IT CUTS AS WHEN TO CHANGE THE BLADE THIS COMES WITH EXPERIENCE. Today I changed the blade after about 1 1/2 and I was cutting 3/4 popular..It just didn't seel right to me.