Neck problem with an older F 30

[shepke]

I noticed recently that I was getting some string buzzing on my much beloved 1968 F30. The neck looked straight with just the slightest amount of relief, so I went to adjust the truss rod a little (something I've done many times before) thinking that a bit more relief would easily solve the problem. To my alarm I noticed that the truss rod was already pretty loose and that there was no way to give the neck any more relief. It can still be tightened, but not loosened. the neck doesn't have any noticeable up bow and seems quite straight when I site down it. My guess is that the neck somehow lost it's natural relief and that this needs to be restored somehow. I solved the immediate buzzing problem by replacing the saddle with a slightly higher one that I keep on hand, and now it plays fine. But I'm bothered by the fact that I can't add relief anymore. Is this something that can get progressively worse until there is an actual up bow in the neck? Is there an easy fix for this? Should I take it to the guitar doc? Help!

 

[Taylor Martin Guild]

Get the guitar humidified to 50% for a week or so and it may be fine.
If that does the trick, keep it humidified all the time.

 

[shepke]

Thanks for the advice. You're probably right. Although I always store the guitar in its case with a Planet Waves humidifier for the body, it's been pretty dry around here this winter and I think I'll add a Dampit or two in the case as well to up the overall humidity level.

 

[shepke]

I've been doing some research online and I came across a posting somewhere in which it was suggested that, for a neck with relief problems like mine (which seems to be pretty rare, from what I gather), the solution is to get a clean paint roller, place it at the center of the fretboard, run the string over the top, tighten them evenly, and leave for about a week. This is supposed to apply gradual pressure to the neck and restore the relief. Has anyone here ever hear about this, or ever done this? If humidifying doesn't work, I may try it.

 

[chazmo]

To be honest, shepke (and I ain't no expert), but I've never experienced a guitar neck that doesn't bow *forward* over time. That's why neck resets are possible -- you shave a little wood off the heel of the neck, and then when you reattach the neck to the body, there's now a slight angle backward which counteracts the forward bow.

To have a loose rod with a straight or back-bowed neck is foreign to me.

Have you been storing the guitar without tension on the strings? I.e., was it back-bowed in the case when it wasn't being played?

I would definitely think that just running higher string tension (maybe try some thicker strings tuned to pitch) would start to pull the neck forward against your truss rod (should tighten it up). But, please, be careful with that. Too much tension can certainly / easily cause damage.

I completely agree with TMG, first make sure you've got the guitar equalized at 50% humidity before making any tweaks. Do that with your strings tuned to your normal tuning pitch.

 

[shepke]

Thanks for the cautionary advice. I'm currently trying to get more humidity to the guitar and will continue doing this for another week or so before I try anything else. The strange thing is that I always keep my guitars well humidified in the winter by storing them in their cases with a Planet Waves humidifier. I also use a room humidifier and leave the guitar tuned to 440 (I play it all the time).

I moved last fall from Illinois to Ohio, and it seems that my current place is much drier in the winter than I'm used to, so this is probably at least part of the issue. Still, there are no other signs of humidity related changes to the guitar (like frets sticking out... etc), and because of this, I'm not 100% sure the problem is simply humidity.

I use light gauge strings and I'll try mediums for a while, as you advice. I don't think there's any structural danger in doing this. I've used mediums before on this instrument, although not for the past two years. Maybe that's the problem - the neck was used to mediums and over the last two years, using lights, it may have gradually changed. So far it plays fine with a very slightly higher saddle and I don't think anyone would notice that there's a problem at all without examining the neck very carefully. But I know, and it's driving me crazy.

Everyone tells me this is a very unusual problem and, in the end, I may have to take it to the Doc.

Oh, by the way, I saw the pics of your new/old F-50R. Damn, that's a nice piece of wood!

 

[kostask]

Thanks for the cautionary advice. I'm currently trying to get more humidity to the guitar and will continue doing this for another week or so before I try anything else. The strange thing is that I always keep my guitars well humidified in the winter by storing them in their cases with a Planet Waves humidifier. I also use a room humidifier and leave the guitar tuned to 440 (I play it all the time).

I moved last fall from Illinois to Ohio, and it seems that my current place is much drier in the winter than I'm used to, so this is probably at least part of the issue. Still, there are no other signs of humidity related changes to the guitar (like frets sticking out... etc), and because of this, I'm not 100% sure the problem is simply humidity.

I use light gauge strings and I'll try mediums for a while, as you advice. I don't think there's any structural danger in doing this. I've used mediums before on this instrument, although not for the past two years. Maybe that's the problem - the neck was used to mediums and over the last two years, using lights, it may have gradually changed. So far it plays fine with a very slightly higher saddle and I don't think anyone would notice that there's a problem at all without examining the neck very carefully. But I know, and it's driving me crazy.

Everyone tells me this is a very unusual problem and, in the end, I may have to take it to the Doc.

Oh, by the way, I saw the pics of your new/old F-50R. Damn, that's a nice piece of wood!

Shepke:

If you have a suitable straightedge, you should put it on your fretboard (strings off), and see if there is any relief at all. If there is some relief, or it is straight, it means the neck is fine. If the two ends (at the nut and end of the fretboard near the sound hole) of the neck drop off, then you have a problem. It will be impossible to know until you can verify that. If you have a straight edge that is long enough (24" or so) push the straightedge forward (towards the bridge) so that you can see where the straightedge contacts the forward edge of the bridge. If it passes over the bridge or just barely contacts the top of the bridge, this is fine. If it contacts the front edge of the bridge, you may be looking at a neck reset; the further down the front edge of the bridge, the quicker it will be required. If it contacts the soundboard in front of the bridge, and immediate neck reset is in order.

If the neck does have relief, but you are still having playability issues, it means that the soundboard has shrunk some amount, and with that the bridge has come down in relationship to the neck. The solution to that is to try to raise the humidity so that the soundboard goes back to its proper shape. This should allow the bridge to go back to its previous level, and allow the use of your shorter saddle. You may want to consider humidifying the entire room in which the guitar(s) reside, and leaving the guitars out in the open, if that is an option for you.

If you have a drop off on both ends of the fingerboard, the neck is back bowed, and may need to be heat pressed. Backbow has more to do with the wood in the neck than anything else. Heat pressing can address the problem, if it isn't too severe; It should restore the neck to being straight (without strings). With strings on, it should bow forward some, which can be adjusted with the truss rod.

Necks don't get "used" to string gauges. The only thing they react to is the tension being applied by the strings (and the counter acting force of the truss rod). The neck will try to return to a stable state (ie. straight, or whatever position it was when it was built) without truss rod counter pressure, no matter what the strings being used are. If the truss rod is used to adjust relief for medium strings, the neck will straighten out (have less relief) if light strings are put on. You have however, stated that the truss rod in your guitar is loose, so any contribution of the truss rod is eliminated. If the neck happens to have been built with a back bow, then it will have a backbow if the string tension is lowered.

Kostas

 

[chazmo]

Thanks, Shepke!

Yeah, it *could* be humidity related, but then now that you mention the string guage change... maybe that's the issue. Or perhaps a combination.

If she doesn't start tugging forward a little, you might indeed need to seek a luthier's advice on that. I'd be very nervous suggesting anything which actually puts more tension on the neck, but a luthier could use some braces and clamps to do that (if that's ultimately what's needed).

 

[GardMan]

You can check the relief w/o a straightedge. Place a capo at the first fret, and fret the 14th fret. There should be a slight gap between the strings and the 6 or 7th fret... you can sight it visually, or I just bounce the string with my finger tip at the 7 fret... you can feel it move, and here a little plink when it hits the fret. IF there is NO gap, you are backbowed. If too much of a gap, you need to tighten the truss a touch.

You might try "bluegrass gauge strings" instead of mediums... light trebles and med bass. They might be a little easier on your fingers (for me, its laways the med trebles that cut into my fingers... med basses are thicker and distriute the pain a bit more).

 

[shepke]

A lot of really good thoughts here. I checked to make sure it wasn't a neck reset problem (per Kostas), which thankfully it isn't. Next up will be medium gauge strings as Chazmo suggested and I'll continue to humidify for a while. It may be that the neck was built with a slight back bow as Kostas said, in which case the mediums should help take care of the problem. There may be a contribution to this from the top ,which I'll be able to determine when its absorbed some more humidity.

I never had this problem before and I'm thinking that its a combination two factors:

1. The natural lack of relief in the neck.
2. a slightly shrunken top.

This would explain why the light gauge strings played fine for so long until the drop in humidity shrank the top slightly and lead to audible string buzzing.

Thanks again for the great ideas. I'll keep you posted

 

[Taylor Martin Guild]

Shepke,
One other thing to think about.
Light gauge strings have a larger vibration pattern than medium gauge strings do.
This will cause light gauge strings to have fret buzz while medium gauge strings may not.

When you have achieved the proper humidity and installed the medium gauge strings, i would think that the fret buzz will go away.

 

[chazmo]

TMG, I hadn't thought of that. That makes sense too... Good luck, Shepke. Keep us posted.

 

[shepke]

UPDATE:

I put the medium gauge strings on and continued to humidify. Almost immediately some relief began to come back to the neck. Not an awful lot but enough so that I could begin tightening up the truss rod a bit. This continued for a couple of days. Everything seems to be OK for now and although there isn't as much movement in the truss rod adjustment as I'm used to, it is certainly better than it was. I think, as one poster above mentioned, it is just a peculiarity of the way this neck was made. Anyway, thanks for all the great suggestions.

 

[taabru45]

Don't know if you caught this on a posting I did about buzzing, and humidifying ...worth a watch. Steffan
http://www.youtube.com/watch?v=iDhIyKkN ... re=related