This is my first post and I just wanted to get your opinions. My buddy Bill gave me this guitar -- a Yamaha FG-230. It's really dried out, so I'm trying to humidify it. The top is bellied at the bridge and dips significantly at the soundhole, bending the fingerboard. A previous keeper seems to have taken a cheese grater to where the fingerboard used to be. The bridge is cracked, and there is a 1 inch long (but very thin) crack in the top. I'm pretty sure the bridge needs to be replaced, which got me thinking about pinless bridges. Then the belly got me thinking about a JLD bridge truss from Stew-Mac. Then I started thinking about changing the top.
Problem is, I have never even tried any repair work anything like this, and I'm afraid I'll kill the guitar, or take it apart and not be able to get it back together. What would you recommend? JLD and leave the cracked bridge? Make a project guitar out of it? Give it back to Bill?
I've attached links below that show the top in all its unglory:
Hi Brian.... OK, so Bill gave you the guitar? .... no cost at all? Hmmm.
Well then, have a good time with it! Maybe try the JLD, or tear the guitar apart, see what makes it tick and experiment like crazy! You'll learn a lot and have a ball doing it. When all's said and done you'll either have a free guitar or a pile of wood.... but the price is right and the learning is priceless. But don't give it back to bill :)
That aside--FG230s are all ply constuction, which is why it hasn't self-destructed since the late 60s/early 70s--rehumidifying will have an effect on the neck & fingerboard, next to nothing on the body. It needs a neck reset; they all do. My suggestion is to convert it to a bolt-on when you do so. Some of the very early FG neckjoints were hide glue, BUT!--they are EXTREMELY tight joints, and no picnic to get out--I just did an FG230 a month ago, it was a beast to pull.
JLD: Yes, but not so much for the belly, as for tone. What it will do for this 12 string, properly installed-- AND properly adjusted--, will have to be heard, to be believed.
Bridge: I'd fill the cracks w/rosewood dust, pack it in well, follow w/ thin superglue. Slight reaming of the bridgepin holes, afterwards.
These are really good guitars; too many of them languish as de-facto 6 strings.
From one novice to another, I just want to offer encouragement. You can fix this thing. I have only repaired a few guitars, but have been successful in all attempts so far. My first attempt was a guitar in similar shape (it only had one string too!) but I paid a little more. Mine cost me 50¢ in a garage sale.
In my very limited experience, I have found that wood has a will to return to it's original form. If you give it the opportunity, it will flatten out and stay that way. With two guitars I have used a little bit of heat and clamps to flatten a warped top. Beware that heat will also loosen glue, so you risk having some braces come loose. But that's not so bad, (in fact it might be a good thing - I'm not sure) you can glue them back in place. On that note, you should have a look (or feel) inside the guitar. There may already be some loose or broken braces.
I can't tell from the photos if the bridge has lifted, but if you have to remove and re-glue it, its not that expensive to replace the cracked bridge. Otherwise, it might still function with the cracked bridge. It's pretty easy replace a bridge, especially if you don't have a fine finish to worry about. But I would get a mirror and have a peak at the bridge plate underneath to make sure its not cracked too. I've never replace a bridge plate before - I hear it's not fun.
I'm a little confused about your description of the fingerboard. It's seems like you must be talking about the pickguard area, not the fret board.
By looking at one of the picture, the action looks really high likely indicating a neck reset. That's a little trickier job, but you can do it and there are plenty of more knowledgeable guys on this site who can help you along. I've done a couple with not too much problem.
That's my assessment, but consider the source. I may be a little too eager to offer advice with my limited experience, but I wanted to encourage you to give it a try. You have nothing to lose. You won't kill the guitar - it's already dead. But you can resurrect it!