I bought a sent of 12-56 to experiment with some lower tunings and I can't get the 56 to fit through the low E tuner. Is there anything I can do that doesn't require filing? Or is that my only option?
I've never had an issue with a 56 gauge string. If they're locking tuners make sure you've unscrewed them almost all the way.
Otherwise, you could unwind the wrappings at the top end of the string in order to fit it through the post. This could have some undesirable consequences though with regards to tuning stability.
Apparently this is my first string change! I made a rookie mistake. The screw was all the way out but it was a case of a very untidy string end out of the packaging that did me in. I cut it straight and it worked like a charm. Boy, I feel dumb.