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Alright, so, I've started work on my instrument, and I was curious as to where I should place the bridge. The scale length is 25.5", so between the nut and the saddles should be that length.

Being that the bridge is adjustable, when I measure the distance to drill the holes to mount the bridge, should I just set the saddles to kind of a middle position so that they can be adjusted later on?

Thanks!

We need a little more info.... like what kind of guitar you're building, and what bridge you're using on it, etc.

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Firstly don't assume because a scale length is nominally called 25.5" that it is exactly that, measure the distance from the nut to the 12th fret and double that, that is the actual scale length. Then go to the Stew Mac site which has a very handy fret calculator, enter your measurement and it will calculate the bridge position for you giving the position for a number of different makes and styles of bridge. That should get you where you need to be.

Try here: http://www.stewmac.com/freeinfo/Referen ... tcalc.html
Colin

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Doh, okay, after I posted I figured I should have included some of that. It's a hardtail bridge, 2-1/16" spacing, and the guitar is a through neck build with 24 frets. The plan is for the fretboard to meet the neck at around the 19th fret.

Assuming that you are going to play the guitar yourself:
Take your guitar that plays in tune with the kind of strings you will use and with the action the way you like it. Measure from the nut to the twelfth fret. Double that number is officially supposed to be called the "scale length"
The bridge saddles have to be farther from the nut than the scale length by a fraction of an inch, called "compensation." It varies with string guage and how high you like the strings above the fretboard.
The numbers that folks give for a guitars scale length are often sloppily measured, and may or may not include the compensation. Measure it yourself.
By measuring a guitar set up way you like you can find out how much compensation you will need.
Myself, I hate it when the fender style saddle piece for the low pitched string has to be pulled so far back that you have to take off the spring, even worse if it gets hard to feed the string through the body into the saddle piece.

Regarding bridge placement, I have found the best way to locate it is to place a thin block under it to raise it up so the strings match the neck angle. String it up, tune it and set the intonation. Move the bridge around for the best intonation, trying to leave as much wiggle room left for the saddles. Mark the hole locations for the bridge on the guitar body. Clarification: this only works with a bridge and separate tailpiece like a gibson style setup.

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From my understanding, 1/16" to 1/8" is typically added in addition to the full scale length, for compensation. I have always added an extra 1/16" and the 6 guitars I have built to date have all intonated correctly.

If the bridge has individual adjustable saddles, as a guide, I would set the high E string 2/5 of the way back from it's fully forward adjustment (towards headstock) and then place it's crown point on the scale length + 1/16" line. This ensures good forward and backward travel.

This is how I was taught to do it at Roberto Venn and it's how I've done it since and it works. Though I honestly don't quite fully understand why extra string length is needed beyond actual scale length. If someone who is knowledgeable in the theory about this and can explain to us, that would be cool.

Perhaps the compensation is related to pressing down on a string causing the pitch to be higher?
I'd like to know the reason as well.

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That is it in a nut shell. To fret a string you must push down on it causing the string tension and consequently the pitch as well to rise. By making the string slightly longer you are compensating for this. All other set up specs will have an effect on intonation and how much compensation is needed. String gauge and even sometimes brand will also have an effect. Compensation can also be added at the nut to farther minimize errors in intonation. I use the calculator on Stew Macs page and find it works quite well for determining bridge position.

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Brian

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

https://www.howardguitarsdelaware.com/

I have used the stew mac calculator as well, to see what it is doing and to compare what I am doing with it's results. And in the two examples I have tried, it simply adds 1/16", or .625, to the overall scale length, just as I had planned.

Ummm... .625 is 5/8's of an inch.

You need to add a zero - thusly: .0625

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

oops typo

Thanks Mr. Brian. By the way, your guitars are beautiful works of art.

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