Guitar Action & Intonation

[deselby]

All pretty much true. With a standard wooden bridge, it's all a compromise, and you will never get all the strings perfectly intonated. You just have to decide which compromises you're willing to accept, and which things are more important to you.

Ain't that the truth. Wes on this in the first 30 seconds or so -

[gcb]

Just want to stress -in line with some comments made above- the importance of getting a correct string height and width at the nut, for a good setup.

I don´t have an Eastman but a Yunzhi. Anyway, both are based on the basic Benedetto design.

With my Yunzhi, the first task was to get the neck completely straight. After loosing the truss rod nut had to put pressure at different points of the neck for a couple of days before tightening it. And to get a true reading I had to use a notched ruler. Why?

Because the guitar as it came, apart from neck bow, also had many high spots that required fret levelling and dressing. Hope that is not your situation but wanted to mention it just in case.

Then, I couldn´t fret an F comfortably and with clean full sound at the 6th string, so had to take care of the nut. So on a quiet day I filed the nut slots very carefully with Stewmac files to the appropriate width and depth. As I said both are important, meaning you have to do this job with the same string gauge you will use on your guitar.

As to measures, I took as a reference Benedetto´s book (page 190):

"With all six strings in position tune the guitar to pitch and, if necessary, adjust the truss rod until the neck is completely straight. Using the appropiate slotting files, cut the string slots in the nut to their final depths. As a guide, the distance from the underside of the 1st string to the top of the first fret should be approximately .010". Since the bass strings require more vibrating space, the distance form the underside of the sixth string to the top of the first fret should be approximately .018"

Bearing in mind that the guitar was not a Benedetto, and lest was I, didn't want to push both of us to the limits, so went from .012 to .022. Happy with the result, considered it prudent to do not go lower.

Coming finally to the specifics of your OP, after all the above was done, while I could intonate the two E strings, the inner ones were never perfect. I could have shortened or lenghtened string distances with a very sharp knife, or a file, but decided instead to replace the wooden upper part of the bridge with a Tuneomatic. That had me taking a lot of metal from the Tuneomatic downside so the bridge could be lowered to the position where strings rested on the fingerboard surface from fret 1 to 20 (my Yunzhi was ordered with 20, not 22 frets).

If you get to this point be sure to measure the distance between the bridge base posts and look for a tuneomatic with the same distance between holes.

As I already had a nickel Gotoh I did some corrective drilling to make it fit over the bridge base. I kept the original Yunzhi ebony base as it fitted perfectly over the top, and the wooden bridge rests untouched on the guitar´s case.

After all that the guitar plays nicely with the action I like (5/64 4/64) but can go down to 4/64 3/64 with no buzzes or dead spots. It has now the fourth set of D'Addario Chromes 012 since I buyed it new at the end of 2013 and required only minimum adjustments. (I don't change strings that often).

Hope this information can be useful.

Good luck.

[DanielleOM]

This really can't be that difficult. I still remember seeing someone detune, move the bridge and get everything set up on his break between sets on a gig one evening.

[sgosnell]

For slotting the nut, I set a stack of feeler gauges the height of the first fret, plus a thousandth or so. I then lay that stack across the fretboard against the nut, and file the slot down to the gauge sack, making sure to angle the slot back parallel with the headstock. If the slot isn't done right, and the angle isn't correct so that the highest point is the front edge of the nut, you can never intonate that string properly. The slot can realistically be the same height as the fret, because that's what you get for the rest of the neck, and it works fine with a zero fret. I never want the slot more than a thou or two higher than the fret, and that thou or two is just to allow for wear of the nut slot over time. I certainly agree that the first order of business is to get the neck straight, then the nut set up properly, than start with the bridge. If you can't get proper action without buzzing, then you need to start looking at a fret leveling. That needs to be done by someone with the proper tools and who knows what (s)he's doing. It's a lot of work unless there is just one high fret.

[gcb]

I use Stewmac's nut slotting gauge and safe slot nut guard set.

[deselby]

I noticed Sadowsky sells what they call a True-Tone bridge. There are two different saddles. One is intonated for a wound G the other for a plain G. They can be bought individually or as a set. Pricey.

True-Tone Bridge – Sadowsky Guitars