Not a good idea to cut on top of board, blade may tend to follow grain of board. When I cut with knife I use a pc. of glass beneath it, also great when cutting Mono. You will be surprised how long blade lasts , oddly glass doesn't seem to dull it. Maybe cause the tip is not in contact totally with glass cutting is being done just a hair above tip. call it overkill if you wish using scroll or saber saw but I find it suits me and been doing it for over 50 years.