I recently got a new squier jag bass. Sounds great but the frets seem to jut out a little at the bottom and cut into my fingers. Is there anything i can do to file/sand them down? And if there is what should I do exactly?
Check out this fret end dressing file at Stewart-MacDonald: STEWMAC.COM : Fret End Dressing File Make sure to watch the video as well.
Also consider the humidity in the space where you keep the instrument. The frets didn't grow, the wood shrank from drying. Unless it is extreme overhang, a file could be overkill.
Not necessarily. One winter season with low humidity will indeed shrink the wood and make the sharp fret ends more noticeable, but just one fret dressing of the ends (using the above mentioned file and technique) will eliminate the sharp ends, and they will never come back, regardless of shrinkage..
I filed mine as well. Last winter it was cold and dry for a longer period. Some frets hurt my fingers, so I filed them down carefully.