I have recently purchased a bosch GHO 26-82 portable planer. When i plane the edge of a board, the planer takes a deeper cut at the start and end of the cut. This isn’t snipe, but after a few passes, the edge becomes quite curved. The sole of the plane appears to be quite flat and parrallel between the toe and sole. Could this be operator error, or am i asking to much from a small tool to plane the edge straight?