When buying a ukulele it is incredibly important to check for issues, as all wooden instruments no matter how well built are prone to movement (due to natural fluctuations in temperature, humidity or happenstance). I recommend two steps before buying a ukulele, (1) first check online to check if your specific ukulele (or ukuleles) of interest have any common issues. Note: Don’t be scared if some people have reported some issues with your dream ukulele, but more pay attention to if lots of people are reporting similar issues.
Here is a brief list of the most common and most important issues to be aware of and how to check for them. If you’re unsure of how to check, you can always ask the salesperson at your local music store to check for you, or bring a trusted ukulele enthusiast along with you to help!
1) Intonation: to check the intonation of a ukulele (how in tune a ukulele is with itself) compare the harmonics at the 12th fret of each string to the fretted note of the corresponding string. If the fretted note is higher it means that the bridge has been glued too far forward, if the fretted note is lower it means that the bridge has been glued too far back. Sometimes, intonation can be improved by a compensated saddle, but usually, it should be pretty close in a well-made ukulele. Classic telltale signs of poor intonation are when despite a ukulele being in tune, some chords always sound a little bit off. This is the most important thing to check when buying a ukulele. Beginners might not notice poor intonation to start with. However, as your ear develops, it will start to bug you! Be warned... even expensive ukuleles can have poor intonation. Always check this!
2) Neck/fretboard issues: the neck should have a slight concave bow. A straight or convex neck will always buzz terribly. Also, check for humps in the neck. To check for these issues, site the neck looking from the nut down to the saddle.
3) Neck angle: to be able to get a desirable action on a ukulele, the neck needs to have been glued to the body at the right angle. Sometimes ukuleles neck angle will be wrong, such that no matter how low you make the saddle the action will still be high. This is incredibly important and one of the worst issues to have in my opinion, as it can’t be fixed. To check for this, press the strings at the saddle down onto the bridge, and the strings should be either touching the fretboard or be very close to touching the fretboard.
4) High frets: high frets lead to fret buzz in specific areas of the uke. Make sure to strum and fingerpick the ukulele up and down the whole neck.
5) Sharp frets: this isn’t a huge issue as it can be quite easily fixed (although it’s a pain… literally). As timber shrinks and expands due to climate changes, seasonally you might feel the ends of the frets a little bit, however, they should never feel sharp or be cutting your fingers! Make sure to run your fingers along the edges of the fretboard.
6) Lifting bridges: the tension of the strings puts quite a lot of pressure on the bridge. Unfortunately, lots of manufacturers don’t glue bridges down properly, and over time can pry upwards affecting the intonation and action, or even fly off. To check for this look at the back of the bridge and check for any gap between the bridge and the soundboard.
7) Warped soundboards: wood naturally moves, but if treated properly it should be stable and flat. If it is already warped before purchasing, it is likely a sign of improperly cured timber or bracing issues. Sight the soundboard from the size and check for humps between the bridge and the lower bout of the ukulele.
8) Cracks: this especially important to check when buying cheaper solid wood instruments, as solid wood instruments are more likely to crack than laminate woods (in premium instruments it is less likely to occur as the wood has usually been cured properly).