Scale Length and String Length and Bridge Position... HELP!!!

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momobanks

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So Im in the middle of another build. I just attached the neck to the body and all systems, so far, are a go! Next step? The Bridge! And of course there are some questions that I have regarding the placement of the bridge.

I am using a Tune-o-matic bridge/saddle. I am using a Gibson style neck with a scale length of 24" 3/4...

And herein lies my confusion... I have been doing some research on scale length with regards to the placement of the bridge. I have been getting some mixed messages regarding the placement. I know it's a matter of fractions of an inch, but, as you know, this can make a difference.

In some places I find that the scale length is simply twice the distance from the neck side of the nut to the top of the 12th fret (2 x (Nut-12th) which gives me approximately 24 3/4" (damn you Gibson for your approximations! :cussing:)... now I use my straight edge ruler measuring device and find the area on the body where I will drill my holes. Of course, with the angled neck, that point is above the body. I've read that this will account for compensation for the string length, or vibrating length of the string, which is slightly longer than the scale length. OK?

Other sources suggest that the scale length and the string length are the same...

Cool, moving on.

Now, when I am measuring for the placement of the bridge, should I attempt to measure with the straight edge resting on the frets or should I be measuring the strings then temporarily putting the string on the neck and drill below where the marked string goes...

Not sure if I'm making any sense here.

Any help is appreciated.
 
Re: Scale Length and String Length and Bridge Position... HELP!!!

AND... I should say, that the nut to twelfth fret is actually 12" 5/16... scale length= 24" 5/8... so where should these bridge pins go?
 
Re: Scale Length and String Length and Bridge Position... HELP!!!

Need to ask. Carved top or flat?

Either way, you will need to drill at an angle to compensate (it's that word again!) for the neck pitch.
 
Re: Scale Length and String Length and Bridge Position... HELP!!!

IME, the best way to find a good bridge location is with a temporary "strung" test, using wood shims to place the bridge at the right height and angle. It takes time, but it's worth it.

With a plain G set, the closest to the nut any saddle will ever need to be is exactly at the scale length, on the 1st string, when using the lightest gauge set that might be used. And the farthest back from the nut any saddle will ever need to be is at the point of proper intonation, on the 6th string, when using the heaviest gauge set that might be used.

So, I put on a set that is 58-48-38 on the bottom and 9-12-16 on the top (though you should choose strings from the range that you might use), and set the plain string saddles all the way forward and the wound string saddles all the way backward. Then put the strings on, with the bridge resting on the wooden supports you've made. Shim or plane the supports as needed to achieve a good string height.

Stretch the strings till they are stable, and break them in for a day. Then, just like locating the bridge on a hollow-bodied archtop, move the bridge around by hand until both the 1st string and the 6th string are in tune at the 12th fret, and the 3rd and 4th strings perfectly flank the center line of the fretboard.

With the bridge still in place, use the largest drill bit that still fits through the bridge's post holes; use it to make shallow locating marks in the top of the guitar. Then remove the strings, bridge, and supports/shims, set your drill press table opposite your neck angle, and drill the actual holes for your bridge anchors.

You end up with a bridge that is slightly more angled than standard, but you know that it will be able to properly intonate any set of strings that you might use.
 
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Re: Scale Length and String Length and Bridge Position... HELP!!!

Implicit, but not stated, in what Itsabass has posted above is that the stopbar tailpiece is already installed.
 
Re: Scale Length and String Length and Bridge Position... HELP!!!

Great suggestions!

You could make it simple and just measure from the twelfth fret, but you could run into problems trying to intonate some of the strings properly. I would go the extra mile and do it perfectly for the string guages you'll be using and follow the instructions from ItsaBass. Yes it is a bit of work and time consuming (don't rush the process...to do it right may take several days at least, maybe a week or so to make sure it's precise), but it will be worth it in the end. There are certain processes in guitar making that shouldn't be rushed. Obviously, this is one of the most critical.
 
Re: Scale Length and String Length and Bridge Position... HELP!!!

Oh, one other suggestion...

Put some thin felt pads on the bottom of your bridge shims to keep from scratching your guitar's top as you shift the bridge around..
 
Re: Scale Length and String Length and Bridge Position... HELP!!!

Good points. I was thinking that the guitar is not finished yet. Some thin felt or thin foam would be good if it is already finished. And, yes; of course your tailpiece needs to be installed first.

Also not stated was that the wood shims should have a lip on the forward edge.
 
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