If it is out of adjustment do you have the experience to get it back? Is the angle off? Why? What causes a neck angle to change? An electric guitar made of wood can shrink over time. As instruments age, the constant string tension can cause the body to become slightly concave, and this changes the guitar neck angle. This doesn’t occur with every guitar, but it is common and changes the action otherwise known as "string height". Sometimes a neck will not cooperate and it's time to make a change and replace it. So you need to ask yourself "Do I feel lucky?"
If you still want to change your own neck there may be other considerations you haven't thought of and further questions come to mind? What do I need to know to do this job? Here are a few items you need to be prepared to completely address flawlessly before attempting to add a guitar neck onto a guitar body or replace one. The following are some of the things you'll need to know:
1) What is the optimum back profile for me? Nut width?
2) What size frets do I need to maximize my playing style?
3) Do I need a double action or single action truss rod in the new neck?
4) What scale does the body support?
5) What tools will I need to change a guitar neck?
6) How can I be sure the strings will match the outside margin of the neck?
7) Do I add strings while putting on the neck so I can see if they look right?
8) How do I set all 4 axis of the neck before I add the screws?
9) Can I be sure the holes in the neck line up with the holes in the body?
10) If not-What do I do now?
11) Do I need a shim? Where does it go? What size?
The consensus of guitar experts agree that a bolt-on neck angle to the top of the body should be somewhere in the area of zero and five degrees. From my experience, this is about right. However, the real question is how do you get just the right angle so as to have maximum saddle adjustment for the action height you need for your strings so they'll play at the exact height you want? The second question nobody seems to address is: what about the angle right and left of center? If you get it right-it's like playing a guitar made just for you. If not-you're in trouble. It happens a lot. What we hear is: "I must have gotten a bad neck from Ebay". We don't often hear: "This job is beyond my limitations". The tendency is overwhelmingly to blame the neck, the guy you bought it from or Ebay, Reverb etc.-none of which are generally the real issue.
If your guitar is set up well and the saddles offer enough adjustment range up and down for you to set the action correctly, you don’t need to change anything. However, if the neck angle to the body is too much and you can’t move the saddles down any further then you have high action and the neck will need a shim. Now, this is a very common solution used by Fender, Gibson, G&L, Music Man and any other guitar company using bolt on necks.
If you have lots of experience this process is easy and it will take about 20 minutes to get it perfect. If not-DO NOT attempt it on the guitar you're taking to the "Gig" tonight with you. Better yet-give it to your trusted guitar tech and let him do his job and try not to do it for him-that's why he's here or "Do you feel lucky?"
