12-string set-up blues

[Rick Homan]

A friend brought me a no-name, laminate 12-string for set-up. The fit and finish on it are quite decent. The action was so high as to be unplayable. The joint of the neck heel to the body looks solid: no finish cracks.

To date, I have:
1) installed JDL Bridge doctor to flatten the bellied top. It worked like a charm, and the guitar sounds great. I used the brass-pin version, because there is no place to drill a hole in the 12's bridge.
2) lowered the nut slots for .012 - .016 string height at the first fret.
3) tightened the truss rod as far as it will go -- I think.
4) shaved the saddle as to not much more than radius.

As a result, the guitar plays nicely in first position, but from about the fifth fret on the action gets high. String height at the 12th fret is 8/64" (3.175 mm) . My friend would like to have it play for fingerstyle all along the neck.

My options would seem to be:
1. Shave the entire bridge down so the saddle can be lowered further.
2. Do a "saw-sand-and-bolt" neck re-set." From its general construction, I am guessing this is a post-1970 mass-produced guitar, so removing the neck is probably not an option.

Any thoughts about getting that string height down? Thanks, in advance!

[Antonio Cotichini]

Nobody is. But everybody should be free to signify his point of view. Nobody is the depositary of the absolute truth.

[Rick Homan]

My friend picked up his guitar yesterday, and really liked the set-up. For him, it was essentially a found guitar, so he thought it worth putting a little money into it to get some use out of it. Tuning it down a step made the action good for fingerstyle all along the neck, and he thought that a good compromise. So, thanks again to all for all the helpful suggestions and for the stimulating discussion.

[Tim Mace]

case closed

[Magnus Hultin]

For this 12-string in particular yes, but I still think it is an interresting discussion.
Not shure the JLD case is closed. I am not saying I will never use it, but is still seems like a compromise to me.

I read Your post on the matter earlier Tim, and I am still digesting it. I´ll try and express my view further but it´s sometimes hard to get the words right in English..., takes time.

[Ned Knepp]

Magnus,
I think a lot of any guitar design is compromise. We brace a resonate top with an X brace so that we can use steel strings. Is this the absolute best way to get the most from that top? Probably not but we really do want our guitars to last. The Bourgeois we put a bridge doctor into is a wonderful guitar but it was also just a bit too lightly braced to keep the bridge from rotating . Please don't think I am denigrating Dana Bourgeois for this. When I evaluate a guitar it is for sound and playability first then construction and looks, pretty much in that order. It is my assumption that any guitar (steel string, at least) that embodies the sound, balance, volume and playability I am looking for will need some attention over it's life time. I suppose it is possible to make a wooden box with strings that will not move but I don't think I want one.

The only other permanent solution I know of to fix this guitar would be to strengthen the bracing that was designed and installed by a Master at bring out the best tone possible in a guitar. The bridge doctor afforded us a permanent fix with the added benefit of reversibility without effecting anything that makes this guitar great. How is that any more of a compromise than rebracing? This was a great guitar before the installation of the bridge doctor and, years later, it is still a great guitar.

Ned

[Magnus Hultin]

And I realise now that I put the wrong name in my last post. It was Your post I was digesting Ned, and I still am.

I appreciate how You describe Your way to evaluate a guitar, it makes perfect sense to me. Compare to most members on this forum I am probably a beginner, and I don´t do guitar repair for a living. Most instruments I have worked with have been Levins or Levin made Goyas, and I have note seen to many severe bellies. Not in need of JLD fitment anyway.

I still think the bridge doctor, the way I have understood its function, removes or delimits one degree of freedom for the bridges movement, and thereby its ability to transfer motion the same way into the top. Thereby it is bound to change the sound of the guitar. Not nescessarily to the worse, but to something differrent.

It seems to me like a guitar with a belly big enough to need a bridgedoctor is either to lightly braced from the beginning, or not handled in a good enough way for it to last.

The only way I can see which preserves the anatomy and function of such a guitar would probably be to change to e new top, identical to the original, or possibly to rebrace it. If the root cause is to light bracing, risk is it will end up the same way again.

One option I mentioned in my first post in this thread would be to let the belly be and change to an adapted bridge. Make a new bridge with the bridge-top shaved to be in the same plane as the strings, lengthwise. I have never done it, and I dont know if it would be a lasting solution, as the force on the glue joint will pull sligtly more out from the top than before.

But then again, this would slightly affect the way the bridge connects the string motion to the top...

I do have an old 70:s laminate guitar (Sigma) in my storage, which has got quite a belly. I have been thinking of making my own version of the bridge doctor, where the part fastened below the bridge is made more like a leaf suspension, to allow more motion in the bridge and still keep it in position. I don´t know what it would prove though, since it is not exactly a master design from start. Still, it´s an idea...

But If the bridgedoctor removes the issue with the belly and still leaves the guitar with a wonderful sound, who am I to argue....

[Ed Taublieb]

Since the repair/modifications have been done and the owner is happy with the results I am somewhat "beating a dead horse"

What I was surprised about was no one mentioned the neck angle changing technique that I associate with Jon Lundberg. That is separating the back from the sides from the heel to the sholders, then increasing the neck angle slighty, reglue and trim the excess back and finally rei-glue the binding.

Anyone have any thoughts on doing this on a reletivey inexpensive (say worth under $500.) guitar ?
Ed Taublieb

[Magnus Hultin]

Found this thoughtful and informative discussion at MIMF, couldn´t resist sharing it.

http://www.mimf.com/library/bridge_doctor.htm

[Magnus Hultin]

And there is more....

http://www.mimf.com/library/bridge_doctor3.htm

After reading this about the induced "stiffness feeling" added by the JLD, I suspect the the guitar may need a modified intonation in the saddlebone. On a non JLD guitar, when a string is fretted, the bridge and top tilts slightly, reducing the amount of extra string tension added by the fretting.

With a JLD, this tilting is, if not removed, at least reduced. The result should be increased tension in the fretted string, which need compensation in the saddlebone.

Any thoughts on this?

/Magnus

[Antonio Cotichini]

Nobody can deny it, Magnus. Physics is Physics. What come in my mind now, about this tread, is the magnitude of the phenomenons we're talking about. I'll try to express my thought.
A guitar, is theory an reality. On theory it should be stiff as rock and don't even need compensations of whatever sort. Practically we have so much variability to front, given by the nature of materials and precision of work, that it's always a big compromise. And these variabilities still vary during the time and the changes of the environmental conditions.
In other words, if the changes we have on the length of a string by fretting, or the amount of angle of a bridge by vibrating is so big to determine an audible difference in sound or a difficulty on playing, there we must do something. Otherwise, if we need to measure it with some electronic device, IMO, we must accept nature and go on playing.
Perfection is not human.
Antonio