About a year ago, my mom was given a guitar by one of her friends; he was moving, and didn't really want it. She gladly accepted, excited to learn to play, and then promptly forgot about it entirely. She eventually decided to store it in my room, under my bed, because she didn't feel like having it around; it's been in our possession for about a year, without really being cared for (sad, I know; I wish I would have taken care of it from the beginning). The input jack was broken when we got it, which led to me never really bothering with it; I'm a bassist anyways, and have never really cared to learn guitar.
Today, I finally bothered fixing the input jack, and cleaning it (good god, it needed it.... the fretboard was disgusting, and I could swear I found chocolate on the back..... I chose not to question the previous owner about this), as well as treating the fretboard with oil, and ran it through my bass amp, to find it working. Now that I'm beginning to actually use it, however, I noticed a problem; the spacing from the strings to the fretboard is three to four times larger at the twelfth fret than it is at the nut....

I don't know much about guitars, but I'm guessing this means that the neck is warped, and pretty badly?
If so, how would I go about fixing this?
That sounds pretty extreme, but try adjusting the truss rod BUT if you don't know how to properly do this I'd suggest going to a shop and having them check it out.
May not be neck warping at all; it may just have insanely high action. What guitar is it?
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A Yamaha EG 112; basically just a wanna-be strat, from what I can tell, but I don't know much about guitars.

Also, I have no idea what to do as far as the truss rod; I've never had to adjust one.
I'd take it to a guitar tech shop, if you cannot cannot find one I would recommend getting this book, Guitar Repair Guide. I bought this book and it is incredibly helpful, it shows you tons of things and should answer pretty much all your questions. I now do my own setups from reading the book.
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Last edited by I am wet : Today at 03:26 XM.
hold the guitar's headstock up to your eye and look down the side of the neck. it should be pretty obvious if the neck is horribly deformed. it should have a very slight bow (inwards, not up towards the strings) or be perfectly straight. if it's very slight or straight you can adjust the action at the bridge. if not then a truss rod adjustment should help. worst case is that neck is just too warped to save but first things first
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It has a bit of an inward curve, but it doesn't look near as bad from that view-point as it did looking at the strings spacing from the fretboard; I'm going to have to look into how to adjust the action and bridge, and see if I get any good results.
hold down the low E string at the 1st fret (us a a capo to help if you have one) and at the fret nearest to where the neck meets the body and see what sort of gap you have at the midpoint along the neck. should be around a credit card thickness. if it's a lot more or less, you need truss rod adjustment. quite honestly what you are describing doesn't seem that extreme. there should be a slight inward curve.

have a read through the 'set up' sticky in this forum.
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