Customer brought a banjo in recently complaining that the 5th string tuner would just not stay in tune. That string is the one which is shorter than the rest of the strings, starting at a higher fret and is usually tuned to a high G. It really throws guitar players off because it is “lowest” on the neck but tuned the highest. Does make for fun patterns when arpeggiating chords.
I don’t get too many banjos through the shop so I had visually inspect the instrument first to see what might be going on. I found that the tuners on the banjo were friction tuners. These are a cheap type of tuner used very often on banjos, and ukeleles. I do not recall seeing the on guitars. This tuner in particular would just not hold the note at the high G and so as useless.
After some quick research online I found what I was looking for, a retrofit 5th string tuner that was geared like a regular tuner. Since the other four tuners were working fine, we decided to leave those and just replace the offending unit. Here you can see the difference between the two tuners.
So once I had the correct replacement part, I removed the old tuner. What was left was a hole in the side of the banjo which was too small to install the new tuner. I had to use a specialty reamer with the end ground off to enlarge the hole enough to fit the new tuner into. This is the trickiest part of the repair: make the new hole too large and the tuner will not stay in there. You want a very tight fit but not so much that you may split the neck wood when installing. Once I was where I needed to be, I also used some slow set wood glue in the hole to help bind the new tuner. Another important consideration is to get the proper angle of the spring post so that the string has some fall away from the fretboard, but also does not end up rubbing against the tuner body and causing a different tuning issue.
After letting the glue set for 24 hours, I strung up the banjo, checked the intonation, and tested the new tuner. Everything worked out perfectly and this budget banjo was better than when it was new. Here you can see the happy customer with her new friend. I highly recommend this upgrade for anyone who has a budget banjo and wants an inexpensive way to upgrade their playing enjoyment. Who wants to keep tuning when you can be playing.