[ctlikon0712]

If your drums are turned to a larger diameter than the shoes, then they will contact in the center of the arc, not out towards the ends. This means you have a much smaller contact patch than you should. I.E. less brakes. Once the shoes have been ground to the proper dia. they need to be centered in the drum. Once centered then they can be adjusted in our out with the wedge. This only affects the drag or preset of the shoes before they are actuated. This is an exaggeration but think about it like this.... If you have a 14" rim in a 15" tire it’s only going to contact the tire's lip in one spot, not all across like it should. Even then the spot could be high or low and not on the centerline. Here is a pic someone posted here before that I borrowed. I have Barrett equipment, but this will get you by....
Good Luck