Now that the neck is glued in place, how do you decide exactly where to put both the tail-piece and the bridge?  This has been lurking around in my thoughts since the beginning of this project.  I mentioned in the earlier post that aligning the neck perfectly with the centerline of the guitar body is critical.  If I simply marked the bridge and tail-piece locations using the template, there is a risk that the strings would not be aligned correctly with the neck.  Also, since the distance of the nut to the bridge dictates the scale length, and the fret spacing is already set to the Gibson 24.625″ scale, placing the bridge posts too close or too far away from the nut will result in a guitar that will not intonate correctly as you work up the scale.  The bridge is usually placed at a slight angle, with the bass end place behind the treble end, resulting in a compensated bridge.  Additionally, the bridge saddles have a bit of adjustment to them, allowing each string to be intonated individually.  But you still need to get the bridge close to its correct location.

First off, the line between the nut and the tail-piece largely dictates how the strings will align with the fretboard.  If you center the tail-piece on the centerline of the guitar body, usually the seam between the maple top pieces, and your neck is not exactly centered and aligned, your strings could run off the edge of the fretboard as you move up the fretboard.  Not a good thing!  You could possibly compensate a bit by placing the bridge slightly off-center, but this will put a kink in the strings at the bridge.

So it is best to locate the tail-piece and bridge in relation to the set of the neck/fretboard.  I was going along this path by laying my straight edge ruler along each edge and down the centerline of the fretboard when I came across a fantastic description by Jack Briggs on the MyLesPaul.com forum (search for “Compensated Bridge Location” on mylespaul.com) of just how to go about locating the bridge.  Once I had that dialed in, I located the tail-piece studs the recommended distance behind the bridge.  It figures that someone else had already figured this all out.  Here’s the text.

If you’re talkin’ LP or most other Gibson electrics, the scale length is 24.625″, not 24.75″ as Gibson has advertised for decades. Here’s what I do:

Measure from the 12th fret crown (center of crown) toward the end of the guitar and make a mark at 12 5/16″ (12.3125″). Pencil a mark in the center. Now I grab my metric ruler, butt the zero end to the fretboard end and measure where my pencil mark is. Note that number (in millimeters). Take that ruler or another straight edge that’s somewhat flexible and put the edge against the edge of the fretboard binding on the bass side, holding it tight against the fretboard. Make a light pencil line down the other end of the straight edge in the bridge/tailpiece area of the top. Do the same from the treble side of the fingerboard. Now with your metric ruler determine the center line of the top based upon these two pencil lines you just drew. Butt the ruler to the end of the fingerboard again. Remember the mark that you made earlier denoting the 24.625″ scale length theoretical? Add 2mm to the treble side and 5mm to the bass side. ARB1’s should be 74mm post spacing, but it’s always good to measure yours. Draw a center line by splitting the two extended lines from the fingerboard edges and using the end of the fingerboard center mark (measure this, too). Center the 37mm mark of the ruler on your center line and tilt the ruler to pick up the bass side mark and treble side mark and you’ve got an angle that will allow an ABR1 to intonate properly.

I take out a couple of saddles and turn them so they’re optimized for the duty they’ll be doing. I want the 1st, 2nd and 4th saddles to have the bevel facing the tailpiece; the 3rd, 5th and 6th facing the nut. This will give the travel you need for full intonation.

Once I had the tail-piece studs in place, I strung up the first and sixth strings, placing the bridge on a narrow shim in the approximate location identified by the Briggs method.  I tuned each string, then checked that the intonation was correct at the 12th fret (it should still be an E).  The line that I drew using the Briggs method (see photo below) was spot on!  This also allowed me to shift the bridge slightly up or down in order to center the strings on the length of the fretboard and over the pickups.

Use a brad point drill bit run down through the end holes on the bridge to mark the post centers before removing the strings and the bridge.  I then pulled the tailpiece bushings using a home-made puller that I made from about $2 of parts at the local hardware store.  It worked perfectly.  And now for some color.