Well, this title will puzzle some folks but those of us experienced 5-string banjo players know that a traditional way of fretting the 5th string on a banjo when you capo at the 2nd or higher position on the neck is by sinking a railroad spike into the fingerboard. True, it's typically a tiny railroad spike, HO gauge, about 3/8 inch in length, manufactured by Varney, with an offset head for tucking the 5th string under. Varney no longer makes these suckers and while cruising E-Bay I noticed someone auctioning them for an outrageous reserve. I recently secured a supply for some 6000 banjo players and would be happy to provide a dozen or so for $1 with a stamped self-addressed envelope. Send me a PM if you're interested.

I used to have just one of these railroad spikes emplaced for playing with the capo on the 5th fret but I was still breaking 5th strings fairly frequently because I often capo at the 2nd fret or the 7th fret as well. I now have three railroad spikes emplaced and things are working much better. To emplace the spike you need to carefully drill a hole in the fingerboard, slightly smaller than the spike, using one of those little hobby drills, being careful not to drill it all the way through the neck in your excitment. You then put a small drop of glue on the tip of the spike, and tap it in with a minature hammer, enough so the string doesn't buzz when it's not tucked under the head of the spike. Good luck!