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I've been trying to setup a guitar I just built. I keep fighting with the tuneomatic though. I'm using a Stetsbar and that's just the bridge that it employs.

Anyway, the fretboard radius is 10"-16" compound so the stock Gibson radius needed to be flattened out (to approximately 18") so I did that the usual way with nut files, sandpaper, etc. The problem is that, when I go up past the 12th fret and bend strings, they die off like they are rubbing on a high fret. I checked while bending notes in that area and the strings appear to have plenty of clearance over following fret(s) as well as the pickups. What convinces me that it's the bridge is that it's happening when I bend at the highest fret. It sounds like the fundamental is disappearing and I just hear a (somewhat muted) trail of harmonics in the wake.

This is not the first time I've experienced this with tuneomatic bridges. I've even manged to fix it in the past but clearly I can't recall how I did it. I thought it was a matter of de-burring the "mouth" of the notch but I guess I just imagined that. Since the notches in the middle have to get deeper, I've tried making a "V" shape to give the string some room to breathe. I've tried angling the groove down behind the saddle as well. I went as far as swapping the saddles out for new ones and starting over. Whenever I make an adjustment, I can usually hear a difference in one area of the fretboard, but then the problem still exists somewhere else.

Anyone here had this problem? I'm officially stumped.

Thanks,
-Aaron

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

If I remember correctly, a tune-a-matic is 12" radius.... But I think your problem is not the bridge, it's the neck.

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"Act your age, not your shoe size" - Prince

Correct


And by "neck", I assume you mean frets. In which case, it should ring true at the highest fret but that is not the case. Would you care to elaborate?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Frankly, I need a better description of the guitar and what you've done...

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"Act your age, not your shoe size" - Prince

I would suspect the frets too and the idea that the fretboard rises over the body what we call a ski ramp. The characteristic of this is it chokes out notes in the upper register particularly when bending. Fender style bolt on necks are notorious for this.

One work around without doing fret work is to adjust the truss rod so that the treble side of the neck has very minimal relief such as around .003" at the 5th - 7th. Of course the rod has no affect on the frets over the body but by reducing relief in the mid section of the neck you can raise the action over the extension frets without raising it for the player in terms of string height over where we actually play the guitar the most. This raising of action also may.... may take the ski ramp out of play.

Remedy two is a fret dress imparting "fall-away" which is specifically engineered to do exactly what we want to do with this one, take the body frets out of play in terms of fretting out with bends or worse.

One way you can test my theory and Chris's too that it's not the bridge or the saddles is to take a string out of the saddle slot and just place it on the top of a saddle. Lower the bridge so that the action is the same at the 12th as when the string was in a saddle notch. If it still chokes out with bends or even just fretting you have a ski ramp on your fret board extension.

It's also likely that if more than one string does it you have a ski ramp.

Lastly not sure how low your action is. It may be too low. Action below .004" at the 12th for the high e is problematic for 90% of guitars out there because the fret work is not high enough quality with fall away to do uber low action.

It's a semi-hollow.... sort of a hybrid of a Strat and an ES335. 25" scale, set neck. Neck and body similar to LP - 3.5 degree neck plane, 1.5 degree pickup plane. Stetsbar hardtail-style vibrato. Two Humbuckers. Nothing too out of the ordinary. Fretboard radius starts at 10" at the nut and flattens out to 16" where the 23rd fret would be. Bridge radius should (theoretically) be ~18.17? Presently, it's closer to 17" simply because I'm stuck on finalizing the saddle notches until I can figure out what's happening with them.

I've labored over the frets quite a bit. Fretwork can be challenging and I'm by no means a wizard. However, I try to pay attention and keep everything in order. I have proper tools for the job as well as reasonably accurate measuring instruments and from what I can tell, the frets are level. If something is a bit off, it shouldn't be enough to completely kill a note. Perhaps you know something I don't?

Is that enough or is there other specific info you need?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

One more thing to check and don't laugh it's been the issue before. Are the pups too high and a string is touching one of them when fretting? Magnetic pull of stronger magnets with a pup too close can result in some weird things too.

On any of my guitars, I generally have neck relief set between .003"-.005" @ the 7th. The idea of neck relief never made any sense to me. Guitars feel (and sound) kinda sloppy to me unless the neck is relatively straight. If feel like I'm working harder when the neck has a lot of relief.

That said... The problem still exists with the neck straightened out and the action raised to compensate. Right now there's 0 relief. Everything plays clean for the most part. Even bends are clean with the exception of that one area.

I'm fine with dressing the extension or even yanking the frets and redoing it. I'm just hesitant to do anything else until I can wrap my head around why the B string dies off when it's bent at the highest fret. What's it hitting? Same thing even with the pickups down in the body. Is it possible for a misshapen fret crown to do this?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Oh yeah... I keep my action right around a 1/16" (.063) at the 12th fret. I wouldn't guess you'd get any tone at .004".

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Is the sound dying when you play the B-string at the highest fret when you have the guitar plugged in? Does it die when the guitar is unplugged? If it only happens when plugged in then the issue may be that you have the pickup at the half way nodal point. If it happens when unplugged then you can rule out that possibility.

Stetsbar.... all I had to hear..... hate those.

I think the problem is the saddles and that the slots are too deep. I modify a lot of bridges for radius.

Up around fret 7 we enter the sweet spot, from here up to about 15 you can achieve the biggest bends thus pushing the strings the farthest sideways...... and into the sides of the saddle slots chocking out the string and sounding very much like bottoming out on a fret.

So take the tops of the saddles and file them down so they are level with the top of unwound strings and about 40% of the wound strings are proud of the top of the saddle. Make sure your slots are cut with the proper gauge file if you will always use the same string gauge or cut them with a tight triangular file to create a V that grabs the string so it cannot shift.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

It's happening when it's unplugged.

Brian,

Thanks. I'll try this.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

I set action for 4/64th" for the high e and b at the 12th and if I said .004" that was a mistake on my part. I'm not rereading anything short on time here.

But what I wanted to add is a ski ramp what I suspect that you have or a high fret can be seen by sighting down the edges of the neck. If you see a rise from the body joint to the last fret that's a ski ramp. These are VERY common.

Another way to check is take that B string and raise the action and check to see if it frets out. If it does not fret out at 5/64" or higher at the 12 th but it does lower you have a ski ramp and the only remedy if you want decent action is a fret dress and inducing fall-away.

One poster here likes to tell folks that they don't see the value of fall away and that's fine it's not my problem. But for others who genuinely are fascinated with this stuff this is a classic and very common reason for fall-away. Again on acoustics with high action fall-away or the lack of it is not as important as it is to the heavy metal vomit music shredder crowd of which I am a proud member when enjoying my scotch. . But I digress.

Raise the action a bit on the b and if the fretting out goes away you have either a ski ramp or high fret. The high fret could be a loose fret too and not in the sense of sexual promiscuity but it's not glued in place well (if at all).

I don't understand how anyone working on their frets would not have an accurate machinist's straight edge (not a ruler). This is the only reliable way to know what is really going on with your fret plane. Trying to push down a guitar string to the frets is a poor substitute.

Hesh, I am a bit late to the acceptance of the benefit of fall away, but I now totally agree with you.

I worked on it for a while and put it aside for a couple weeks because I wasn’t making any progress. Now I’m back to it and still not having much luck. I originally installed the frets with medium CA. I’ve checked for ramps, humps, high frets, etc. I found a couple of questionably high frets with a fret rocker and did some careful leveling but the playability of the guitar neither improved nor worsened. I tried raising the action considerably as a diagnostic measure but high bends are still dying out. I considered the remote possibility that the fretboard extension wasn’t glued securely but I can’t find fault with the joint. I considered that perhaps I skimped on the glue while installing the frets so I squeezed some thin CA down into the last 10 slots and sanded a slight fall away from the 15th to the end of the extension. No improvement. The radius is 10-16. One reason people use this radius is because it is supposed to give more clearance for bending further up the neck. As stated earlier, I don’t claim to be the best but.... after building a few dozen instruments over the years I didn’t expect to be stumped like this. I do appreciate the people on this forum helping me work through it. This one continues to be a doozy.

Brian, would you mind elaborating?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

As a diagnostic device, could you make a temporary replacement for the Tune-o-Matic bridge - I'm thinking of a scrap of rosewood with a hole drilled either end to take the machine screws and a piece of fretwire to replace the saddles? That should be a quick job.

If the problem goes away with that temporary bridge, it tells you that the problem lies in the bridge itself. If the problem remains, that tells you it's somewhere in the fretboard.

That’s a great idea. Since I have the stetsbars that is meant to fit the 5 hole pattern of a hard tail strat bridge, I decided to just order that bridge. With a shim, I should be able to mount that to determine if the problem is bridge related. Should be here in couple days.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."