Hobby saws are available in both 'push' and 'pull' configurations, referring to the stroke on which they are designed do their cutting. Though 'push' is most common, I usually look for a 'pull' blade. For years, before I knew both types were available, I always used the 'push' blade in the 'pull' direction in the mitre box, as Tom mentioned above. Regardless of which type of blade you have, you will likely find better control if used in the pull direction. Even a 'push' blade will cut/wear through plastic and soft metals when pulled, and sometimes with better control than using the proper 'pull' blade. I also find that a 46 TPI blade (Teeth Per Inch) or finer is preferable for model work.