Wilkat's Help Tips © 2001
So your neck's warped -- or is it?Most guitar players that I know, don't know (or care) how their neck is adjusted , they just want to play their guitar, and have a fast neck with smooth action. You might feel the same way. However, if your guitar doesn't feel right, or is difficult to play, it may be due to the neck adjustment. I've heard a lot of guitar and bass players say things like: "Jeeze, my neck's warped and the dang thing won't play right!". Well, they are usually wrong (not about the feel, but about the warp). Of course, if looking down (viewing the top of the fingerboard), your neck curves to the left or the right, you've got a real problem that won't be discussed here in this tip, and, you will need to consult a qualified repair man.
Here's the thing: A stringed instrument's neck needs some relief clearance from the strings (to avoid buzzing and rattles), and that warp they are talking about is normally visible as "up bow", caused by the pulling force of the strings when they are tuned to pitch. Conversely, they may have a neck with "back bow" which can be a more serious problem, and may require the assistance of a professional luthier.
Let's look at "up bow" first:
Wood bends, and that's why we install truss rods in guitar necks.
NOTE: Some truss rods are not adjustable, and these are more commonly found in some makes of acoustic guitars. The makers of these types of guitars select a predetermined rod or channel to resist "back bow" and limit "up bow". Making adjustments to these types of guitars will require help from a skilled luthier (and there are limits to what can be done). However, quality manufacturer's products will not normally need a neck adjustment, and often rework of the bridge and frets can solve the problem (again a skilled luthier should be consulted).Modern guitars feature adjustable truss rods. Some work in one direction, while others are capable of 2 - way adjustment ( to correct "up bow" or "back bow" ). SEE FIGURE No.1 The load (or pulling force) acting on the neck varies depending on our choice of strings (light or heavy gauge), and the resistance of the neck to this load depends on the strength of the wood used and the stiffness of the truss rod within the neck. So, if your guitar was originally set up for light gauge strings, and you've now installed a heavier set, you 'll find that the action is suddenly higher than it used to be, and playing comfort has been compromised.
Figure No. 1
NOTE: Stevie Ray Vaughn used heavier gauge strings, but he also tuned down many of his guitars to E flat, which reduces the tensional load of the strings. If this doesn't give you what you want, read on.
So, how do we fix the problem?WARNING: Never turn the truss rod adjusting nut more than one quarter of a turn at one time. Allow the neck to "set" for a while, re-tune, and examine the "bow" and test play the instrument. If necessary, continue adjustment, using minor increments of rotation (usually anything more than a ¼ turn is not required). Never use extreme force to adjust a truss rod or you will strip the threads--if it doesn't rotate easily, it may be necessary to remove the strings, and the neck may have to be gradually bent back using clamps (and sometimes heat) before truss rod adjustments can be made. If in doubt, take your guitar to a qualified luthier for professional assistance.
Simple: If you have too much "up bow" tighten your truss rod by turning in "clockwise" (right-hand) direction. If you have too much "back bow", loosen the truss rod by turning "counter-clockwise" (left-hand) direction.
NOTE: Some guitars / basses have their adjustment nuts at the head stock, while others are located at the heel. Different styles of nuts are also used (some require Allen keys, some use hex nuts, etc.). Regardless (unless otherwise stated by the manufacturer), the adjustment procedure will be as described above.Also, bear in mind that the method of adjustment is normally the same for one-way rods or two-way rods. The difference is that two-way rods normally employ two threaded rods, so in one direction you are pulling, while in the opposite direction you are pushing.Is that all?
Not necessarily! You may still find that your instrument is buzzing or fretting out in some areas. This can be caused by a few high frets (or as can often be the case, frets that have not been properly leveled--especially towards the heel end of the neck). How come? Well, for one thing, if you own a factory mass-produced guitar, the frets will likely have been subject to a basic leveling job. This isn't true of all factory produced instruments, but it is more common than you'd think. Among the things that happens to bolt-one neck style guitars, is that the heel area bolted onto the body gets affected by moisture and can actually swell upwards, making it rise higher than the frets forward of the heel. In fact, the frets towards the body should be lower than those towards the heartsick, and there should actually be a fall-away towards the body. SEE FIGURE No. 2 This will permit the lowest possible string action, and increase the pleasure of playing the instrument -- especially when string bending ( and we all love to bend those notes!!! ).
Figure No. 2
So what do I do if my frets are a problem?Well, if you're a "do-it-yourselfer", you can attempt to file the frets and eliminate the problem. However, without the proper tools and experience, this can be a "risky" endeavor for most individuals. Again, if in doubt, take your instrument to a skilled luthier for fret dressing. He will have the correct tools and know what to do (and the cost may be far less than what you'd think--not to mention avoiding a costly re-fret job if you screw it up before you get there!).
If you have any questions, please e-mail me, and I'll reply as soon as I can. Until then, keep on plucking, tapping, slapping, bending and making those sweet sounds that we all love!
Still Buzzing a bit?
Please note that sometimes a little bit of contact between some of the frets and the strings will still be present--especially if you have the action set extremely low. Usually this is not a reason for major concern, and will lessen after the frets have been worn-in after playing. If you can't live with it, you may need to set the action a bit higher by raising the bridge saddles or having the frets dressed by your repair man. Of course, buzzes and rattles can also be caused by worn nuts and bridge saddles, so listen carefully when you pluck the string(s) to determine the source of the problem.