Hi, I am building my first guitar and have cut the fret slots with a japanese razor saw, however the slots seem too narrow to get the frets in. Is there any danger of splitting the fret board if I press them in without widening? The only other blade I have is a hacksaw blade which is too wide by about the width of a bee's... It's too wide and the fret that I tried it on is not seated firmly enough. Any suggestions appreciated.