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!

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Finally. Now it seems somebody reached my point of view. Dave, that's what I'm saying from the beginning. You'd install a JLD if the guitar has a bridge problem. You'd use a crouch if you'd be lame. If it would be a momentary leg disease you'd throw away the crouch whenever you recover. If you can't recover you'll walk forever with the crouch. Ergo: JLD is a crouch.
I recently played and inspected(ha) the Breedlove,a great archtop and an acoustic which had the
fulcrum sys built into it. It weighed so much as to immediately turn me off. Not a comfortable instrument in my hands.I'm not knocking the co. just too much add on for me.Though as a remedy I think differently.Great points Rick!
Landola had a serie of steel string acoustics with JLD
(maybe still has?)

I tried several and loved the tone. Not high in volume,
but rich in harmonics, long sustain and very even.
Perfect for picking.

I have myself added JLD to a fan braced classic,
in order to play steel strings with the wider fretboard,
and the tone reminds me of the characteristics from those Landolas.

Seems like it takes away some of the bassy power, for the benefit of highs
If, as somebody said, a Bridge Doctor improves tone and enhances volume, the same should happen via that old solution!
Probably it's a little more expensive but without being ugly.
Magnus, is it a copy of an old Stella lying in its coffin? R.I.P.
Don´t really know, borrowed the photo link from This Ebay auction.
looks like a Washburn or Bruno to me.......I like that shape!Click!!!!!
Guitar's shape or coffin's shape, Tim?
wake me at nightfall
My brother and I did put a JLD device in a Bourgeios with extremely good results. It is correct that we did it to correct bridge rotation but it has no discernible effect on the tone or volume of the guitar. We would not have left it in if it had. (On a six string there is no reason to use the heavy, ugly brass mounts since there is almost always room for a screw behind the pins.) Is it a "crutch"? Maybe, if you think it is but this guitar has worked very well with the device in place for many years now and the owner has has no reason to even consider it much less think about removing it.

I remember that one of my class mates once showed up to school with a pair of spiked running shoes for our physical education class. Were they a crutch or were they a device that fixed a problem he has with slipping on the track? As long as he was running on the track, why not wear track shoes? Will the bridge doctor ever be removed from this guitar? Perhaps, someday, but I seriously doubt that it will be because the guitar is "better" in any discernible way without it. Does every guitar need a bridge doctor? I don't think so but that doesn't mean it is wrong/incorrect to install one and leave it. If it works....

BTW, the device we installed was very light and probably doesn't weigh any more than a stronger/thicker bridge plate and beefier bracing and it has much less contact with the primary areas of top vibration. The guitar sounds wonderful. As good as it ever did. Perhaps the system does stop a bit of top movement but I would have to know how much rocking movement a guitar face actually has to be concerned about it. In every way that I can see, and hear, this device corrected an undesirable attribute of this guitar in a simple and direct way with no negative side effects. It just works.

One thing to consider when making a switch to a tailpiece is break over angle/ down force on the bridge. Archtop instruments usually have more angle to the neck set and a steeper approach to the bridge from the tailpiece than is usually available on flat top guitars. It will also increase string length and tension at pitch, shift pressure to a part of the guitar that wasn't necessarily designed to handle it. These aren't necessarily stoppers but you should remember them if you try this.

Totally agree with everything you say. I don't see the JLD as an aesthetics problem. I don't use the bridge pin variety but would if it were to be regarded as a reversible fix on a high end guitar. The single bolt type is an excellent fix for top problems and I regard it as no uglier then the soundpost in a fiddle and for the same reasons i.e. they are out of sight whilst performing an essential function. Elegance is hardly an important factor; if that were the case would we design bracing with that criterion solely in mind. The greatest luthiers, however well they select, are still at the mercy of their materials, and since we are all experimenting, can push the limits of those materials just a little too far. Given those circumstances,and without rebuilding we should regard the JLD as becoming an essential part of the guitar. I won't call it a "crutch" because even with a crutch a disabled person's performance still does not match that of the healthy and IMHO the JLD restores performance plus on occasions a little bit more!
I have always regarded the tailpiece option as a horrendous last resort and if we are talking aesthetics here youe will surely agree that a tailpice completely destroys the elegance of a well-designed fixed bridge guitar.
To be clear on this, I have never considered that a tailpiece is a better solution than the JLD or bridgedoctor. I am only pointing at this as a traditional solution to the same problem. I have also never expressed that a JLD would be ugly, I don´t think it need to be visible externally if mounted smartly.

My point all along has been that the vibrations induced on the guitars top is changed. If the experience by most is that it is for the better, then fine by me, and I really can´t argue with that. I have no experience of my own in any direction.

I still cannot get around that a JLD type of device disables the rotational movement of the bridge. This means that the total height of the saddle, measured from the guitars top is insignificant as soon as this device is mounted. I allways thought this was important to tone and sound on a standard type bridge.

I would assume that if this solution is included in the original design of the guitar, the bracing system and/or the tuning of the guitars top structure should be adapted accordingly. Just as I assume that the bracing need to be differrent of a guitar with tailpiece. The guitar works differently...

Again, I am a novis in guitar design, but I do some guitar repair and I do a lot of thinking. And I am not at all always right.
I think you are correct "that the vibration induced in the guitar top is changed" but this happens every time I shift my arm to play above or below the sound hole too. I would bet that laying my arm over the edge of the lower bout of my guitars has more effect upon the vibrational energy induced into the top than a couple of oz. of BD has.

I know from experience that a bridge doctor will return a rotated bridge to is original position and I assume that it could over rotate one too but I think it would actually take a lot more pressure to do that than return the bridge to it's original position. Beside that, I'm not so convinced that it stops all rotational movement when the strings are struck/plucked.

A bridge doctor, by design, could only stop rotational movement in one direction not both and the brace shaft is a wooden rod which has some flex to it so I doubt that all motion in the forward direction is completely canceled anyway. Beside, the whole guitar vibrates, not just the area around the bridge. Yes, I have a fairly decent understanding of how vibration is coupled to the body of the guitar but I just don't see a BD holding the bridge that firmly in place.

My experience with the BD was that the device doesn't have to be screwed down really tight to do it's job. The top bracing isn't completely removed from the equation. Remember that the top held up for several years before this repair was required. Sooner or later the bracing / BD will reach equilibrium with the job being handled by both. ( I suppose this adds to the argument that a BD is a crutch but I suppose we could call an X brace a crutch too since it also allows us to string our guitar with higher tension than ladder bracing. )

The height of the saddle isn't anymore "Insignificant" with a BD that it is without one. The only thing that changes is that the BD can return the bridge/ saddle to a position much closer to it's origin. It's primary purpose is to correct over rotation of the bridge. It doesn't actually move the bridge/ saddle vertically, it rotates back into position. It would not correct a high saddle on a new guitar with a flat top. That's a setup problem. so if the neck angle, relief or other factors in the setup stay the same, a BD should return that guitar to very close to the original action. If any of these other factors have changed too, the BD may be a starting point but the setup may still need to be adjusted after the rotation problem is fixed, and that may mean adjusting the saddle height.

You mentioned that the bracing of guitars with tailpieces reminds me that that is another caveat to consider when thinking about fitting a tailpiece to correct bellying; Most of those old guitars that we see on ebay with tailpieces are ladder braced.



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