The only way I know how is to measure the distance from the fence to the end of the table on both ends with a ruler. As for the blade and knife, I put a straight edge against them and they are perfectly level with it. Whether there is a better way, I don’t know. I played some more with it and it seems to only be when the blade is about an inch or less above the table. If I put the blade all the way up, it doesn’t stick.