Thomas, once you successfully cut a few long straight lines, doing so will become second nature to you. What type of blades are you using to try to cut the straight lines with, spiral or flat type? If you trying to acomplish it by using spiral blades, then good luck to you, it's very hard to do with spiral blades. If you using flat type blades, then you just need to practice and you will catch on on how to do it. On my saw, an EX21, the drift (deflecion) of the blade to cut a straight line is about three degrees. All that means, is that to cut a straight line with a flat style blade, I have to feed the stock into the blade at an angle of about three degrees off of straight on to the blade. I have never tried to cut a stright line with a spiral blade, but, I've read many times of how difficult it was to do.
Len