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JohnLovesRush
04-10-2008, 01:38 PM
Well the temperature is getting warmer and I have been told that sometimes the summer months can sort out slight warps in a neck.

however I was wondering if you take the strings off the bass.. will it give it more of an opportunity to straighten or do the strings not effect it?

thanks!

SDB Guitars
04-10-2008, 02:12 PM
This is one reason why you have a truss rod in the neck... to compensate for the seasonal movement in the neck

JohnLovesRush
04-11-2008, 10:13 AM
well the truss rod can't actually turn anymore.. i don't fully understand it but apparently it can't be straightened.. still would strings effect it?

SDB Guitars
04-11-2008, 03:21 PM
Take the strings off, take the neck off, and loosen the truss rod until it is slack. Let the neck equalize and check ont how straight it is, checking for both bowing and twisting. Only then will you be able to get an idea of what it might need.

alexgeddy
04-11-2008, 03:36 PM
John, yes strings will affect the relief of the neck....I have a similar issue with a fender....no adjustment on the truss rod left. the "official fender fix" is to take the nut for the truss rod off and put washers between the end of the truss rod and the bolt. this was done on my bass and it works. But I don;t think it's a permanent solution. I did this fix and went to a lighter gauge of strings and haven't had problems for awhile....Hope this helps

if you need any more info on what I did feel free to PM me

good luck,
Bill

JohnLovesRush
04-11-2008, 04:01 PM
ahh thanks for the help guys..with regards to taking the neck off and loosening the truss rod and checking for bowing and twisting thats not something I think I would be the right person to do.. wouldn't want to mess it up.. however I will take the neck off and loosen the truss rod for now and maybe bring it to a pro?..


John, yes strings will affect the relief of the neck....I have a similar issue with a fender....no adjustment on the truss rod left. the "official fender fix" is to take the nut for the truss rod off and put washers between the end of the truss rod and the bolt. this was done on my bass and it works. But I don;t think it's a permanent solution. I did this fix and went to a lighter gauge of strings and haven't had problems for awhile....Hope this helps

if you need any more info on what I did feel free to PM me

good luck,
Bill

hmm I amn't too sure if i'd be keen on the temp solution, prefer to get a more permanent fix if I can.
It's really getting my goat because I spent 500 on this..fretless jazz.. 89, Japanese and it's a total pain to play because of the neck... so try fix the neck seems the reasonable idea.. but if that can't be done at a half decent cost I'm a bit lost with what to do then:(

JohnLovesRush
04-11-2008, 04:41 PM
ok quick update I have take off the neck and loosened the truss rod.. and the neck seems not to be straight..

Nelson Guitars
04-11-2008, 11:33 PM
Back bow? Front bow? Twist? What is it doing?

If the neck is not close to straight or with a very slight back bow with no strings and no truss rod tension then perhaps you need to have it straightened by a qualified luthier. One technique is to heat the neck and press it into shape with a stout straight edge and careful clamping. Not something for the unskilled or weak of heart. Removing the FB and reattaching with the neck held properly can fix this too, but then you get into finishes and all sorts of other problems.

Another option for small bows is to flatten the finger board with planes, and sand papers. Again, you really need to know what you are doing here and be able to evaluate all the variables before attempting to do this.

Are you sure it is the relief that is at issue or the action? People get those two confused all the time and do some pretty strange things to correct problems that don't really exist.

Greg N

JohnLovesRush
04-12-2008, 09:31 AM
I see,, the main problem is I ain't too sure how to distinguish between a front bow back bow and twist,

and about the relief problem.. basically the relief can be put very low..but it just buzzes like crazy.. the lowest point the relief can be set to without buzzing is not very low, thus making it quite a pain in the backside to play.

again, I am no expert so I took a few pics of it.. probably won't help at all but if you'd like to take a look they're here

http://img441.imageshack.us/img441/6286/neck4kl5.jpg

http://img170.imageshack.us/img170/8074/neck2jn9.jpg

http://img170.imageshack.us/img170/8177/neck1eb3.jpg

http://img183.imageshack.us/img183/1529/neck3fo1.jpg

I don't think the perspective is that great.. so it may be totally impossible to tell.. on two of them the bass is in line with the desk it's on.. and currently the truss rod is quite loose.

thanks

Nelson Guitars
04-12-2008, 10:21 AM
You are right. The pictures do not help much without a straight edge for reference. I can't trust that what ever bow I may see in the shot is really there or just distortion from the lens.

Let's get the nomenclature straight.

Back bow: Fret board curved so that a straight edge placed on it will touch only at one point and rock back and forth over it.

Front bow: Fret board curved so that a straight edge placed on it will touch at both ends and leave a tapered space in between.

Relief: A controlled front bow. Lot's of opinion on how much and where this should be shaped (and even if it should be there at all) but I like to place the maximum relief somewhere around the 14th fret. More relief is required on the bass side than on the treble side especially with fretless. This needs to be worked in to the shape of the finger board itself if you want really low action. Just taking a straight FB and adjusting the truss rod won't get you there.

Twist: Any condition where a hypothetical line drawn parallel with the nut is not in the same plane as a similar line drawn at any point along the FB.

Action: The relative height of the string in relation to the FB at a given point (typically measured at the octave/12th fret).

Action is effected by relief and vice versa, but they are distinct and separate issues.

Now that we have the terms straight can you give us a better description of what your issue is?

Greg N

JohnLovesRush
04-12-2008, 12:06 PM
well basically the best way I can discribe it is this.

From looking at it a good bit.. the neck is going out from where it would meet the body to the head of the bass.. like there is relief.. basically like there is a good bit of relief in the neck.. however according to the guy in the shop that the neck cannot be straighten. as if at a point the truss rod will stop turning..but still while there is relief in the neck if ya get me?

the guy said in the shop that "moisture had gotten into the lower part of the neck"

this basically means that no matter whats done with the bridge..the action non buzz will still be high

SDB Guitars
04-12-2008, 12:25 PM
The "washers trick" is a valid means of adding more adjustment to the Fender style truss rods. When you bottom out one of these truss rods, you are, essentially, out of threads for the nut to "pull on" to straighten the neck. Adding the washers means that the nut hits a "stop" before running out of threads, giving it the ability to pull a little more on the neck, straightening it.

When I was in college, I straightened an old '70's Ric guitar neck (neck-through, so it was difficult to clamp the way I wanted) by clamping the neck in a *very* slight back bow, and placing it in a storage unit in Oklahoma City in the summer. The unit wasn't temperature controlled, and I know it had to get well over 130 degrees in there for long stretches. I went on summer vacation, and when I got back, I checked the neck, and it was perfect! It still is, to this day.

I wouldn't call that professional, by any means, and I wouldn't recommend it in most situations, but the principle is the same as what Greg Nelson said above... heating the neck while it is clamped in the position you want it to take. in this case, *repeated* heating and cooling of the wood for 2 months. ;)

I'm a little more scientific about it now, but I was a 19-year-old college kid with a pawn shop guitar I was desperate to make playable, because it had such a cool vibe.

55-02
04-12-2008, 12:28 PM
Well, when I was charging for setups at GC a common problem I saw on "cheaper" instruments was a maxed out truss rod.( I am not saying your neck is cheap)
Here is one method of striaghting I used very often.
1.This is a two man job.
2.Leave the neck on.
3.Leave the strings on as close to full tension as possible.
4.Loosen the rod to give yourself some flexbility.
5.Place the bass body on a table or counter.
6.Have your helper hold the body down firmly.
7.You will be looking down the neck at this point.(crouching normally)
9.Take the headstock and litteraly bend it back to where there is a little of front bow.
10.Tighten the rodd to OEM spec. (Dont over tighten, youll feel it)
Normally the neck will hold just right. Plus now you have a rod thats not maxed-out anymore for fufther tweaking.
I would charge about 50 for this task and it always made the customer very pleased.

GoodLuck

JohnLovesRush
04-12-2008, 12:39 PM
hmm I shall give that a go.. hopefully I don't f up the neck:)

JohnLovesRush
04-12-2008, 12:39 PM
actually there is a problem with that..this is a screwdriver truss rod and thus can't be adjusted while the neck is on the bass..:(

Gio S
04-12-2008, 12:48 PM
There are special tools for that kind of adjustment.

JohnLovesRush
04-12-2008, 01:15 PM
which I don't have lol

JohnLovesRush
04-13-2008, 02:15 PM
just an update.. from doing some little truss rod turns myself.. nothing major

it appears to be a back bow.. if that helps?

Nelson Guitars
04-13-2008, 03:18 PM
So I hope you are loosening and not tightening your truss rod. That would make the back bow worse. Take all the tension off the truss rod and then look at it again in the morning. These things take time to relax into the new order of things.

Greg N

JohnLovesRush
04-13-2008, 03:36 PM
it's loosened fully..I'll leave it till morning so thanks

JohnLovesRush
04-14-2008, 11:50 AM
ok well took a look at it.. as expected action is gone lol.. em m however it looks now like a real front bow..ie there is a dip in the middle of the fret board.. however is this because of the loosening of the truss rod?

SDB Guitars
04-14-2008, 12:52 PM
Gently tighten the truss rod (while the neck is off the body) until the neck is straight, then let it sit for a day or two. Put the neck on and string it up, and see what your action is like Truss rod adjustment can be a trial and error processes.

Just a thought, you *might* consider replacing your truss rod nut with one of these:

http://www.stewmac.com/product_images/1lg/0980/Spoke_Wheel_Truss_Rod_Nut_Detail.jpg

Can be purchased here:

http://www.stewmac.com/shop/Truss_rods/Adjusting_nuts/Spoke_Wheel_Truss_Rod_Nut.html

That way you don't have to take the neck off to adjust it. Only requires very minor modification to the body and pickguard.

JohnLovesRush
04-14-2008, 12:57 PM
ah I have taken off the scratch plate and can now adjust with the neck on.. slightly tricky but not too bad.. I don't tihnk it's a problem with getting the neck straight.. like.. I don't think turning the truss rod can take the bow out of the neck.or whatever is wrong with it.. other possibility is maybe bridge problems aswell.. bridge is crap I think.. G string is too low..