sighting and adjusting a neck?

[Newman]

I recently bought "the bass player book", put out by bass player magazine. It has a section in it about setting up your bass. The article called sighting the neck is a little unclear to me. It's about telling wether your neck is concave convex or striaght i think. Could anyone tell me a little more about this since I didn't understand the books explanation? All I can say is i have a pretty cheapy fender precision imitation. I get fret buzz but i always thought it was something to do with my bridge being to low, not anyhting to do with the truss rod. Well if anyone has this book and would like to explain it. Actually, even if you've never heard of the book it could still help. Thx

[Chris A]

You'll get more responses in Setup. So we're moving up there.

Chris A.

[rllefebv]

Newman,

To sight down the neck, sit down with the body of the bass at your feet and the headstock near your head. Line yourself up so that you are looking down the 'E' string with one eye...what you are looking for is the curvature of the neck, in relation to the string. Since the string will be straight, this should be relatively easy to spot.

Another way to check this without sighting is to sit down with the bass in playing postion. Press down on the 'E' string at the first fret, and while holding that, press down on the 'E' string at the highest fret, essentially holding down the string at both ends of the neck. There should be a gap at the twelfth fret, (typically a good measuring place). The amount of gap is the amount of 'relief' your neck.

There are various theories on how much relief you should have, and your book probably has some good guidelines. This relief is adjusted using the truss rod. Tightening the truss rod will decrease the relief, loosening will increase it. CAUTION!!!! Over-tightening will snap the truss rod like a twig! I'm sure that your book will explain this, but patience is the key. A quarter turn can yield big results, and it is usually a good idea to let this bass sit for a day with the strings tuned before checking the relief again, or making another adjustment. Your neck is made of wood, which needs a little time to acclimate...

Well, I hope that this long-winded reply helps! Good luck, and more power to do-it-yourself-ers!!

-robert

P.S. Usually, you will need a bridge adjustment for string heigth and intonation AFTER truss rod tweaks. Again, this should be in that book. rll


[Edited by rllefebv on 01-14-2001 at 09:58 PM]

[Newman]

thanks alot rllefebv, you obviously know your stuff except what u said was pretty much what the book said and I'm still comfused! what am I looking for? how much relief should their be? what is a back bow and an up bow? Am I looking at the shape of the frets? fretboard? strings? Thanks again

[Marty Forrer]

the reply by rllefebv (sp?) is correct. What you are looking for is a small amount of gap, about 1mm, between the bottom of the E string and the top of the 12th fret, when holding the string down as he stated. If you have a bigger gap than that, you need to turn the trussrod clockwise a quarter turn, leave it a while, check it again. If you still have a bigger gap, turn another quarter turn, and so on. If the truss rod starts to feel tight, and the neck is not moving, you should take it to a tech. If you can comfortably achieve that gap (the relief), then move on and adjust the bridge saddle heights to where you want them.