So I got a new ukulele and was wondering if I could improve on my old $35 Hilo. The action on it is incredibly high and is very difficult to play. I have heard that lowering the action on the saddle is easy (remove and sand from bottom) but I think the high action on mine is coming from the nut. So, long story short, how do I lower it from there? Is it worth trying or is that kind of operation only for the skilled?
Two ways. You can either remove the nut and sand the bottom like you do the saddle, or you can deepen the grooves one string at a time. I'd check the action at different points along the fretboard before proceeding. I'd also check the neck to make sure it's not bowed up so high that adjusting the nut and saddle won't do any good. In other words, it could be that something else might need to be done instead.
One last question...Does the nut need to be affixed to the neck with glue? If so, what type? I'm thinking of maybe dropping 60 bones on a new (set up) cheap uke from MGM but I don't want to give up just yet...
If you're adjusting the action, do it at the nut first. It really does work out better like that. Much easier to judge the action at both ends if you do it in the right order.
Like Dave said, you can adjust the nut in two ways. Personally I'd recommend working on the individual slots if you can. Easier to get a truly custom action allowing for things such as a little extra height for the notoriously rattly wound strings etc. Also, sanding the bottom of the nut can occasionally result in a slant or a lean if you don't keep it exactly perpendicular while working on it.
I'd glue the nut. One tiny spot of CA / superglue or Titebond on the face of the nut that butts up against the fretboard end will do it. Do not put glue on the bottom of the nut. If you put the glue in the right place the nut can be removed easily and safety with a sharp but gentle tap away from the fretboard. Put it in the wrong place, or use too much and you risk tearing out some grain from underneath when you next remove it.
