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I just got the Gallagher in my shop that I'm supposed to replace the bridge on. I could make the bridge exact to the old one and glue it in the exact same spot but I would like to know the scale length so I can rout the saddle slot in just the right spot.

I measured from the nut to the center of the saddle slot before removing the bridge and it measures 25 3/16". Even if I subtract .15" for the saddle compensation I get 25.0375. How can I know exactly where to rout my saddle slot?

What is the length from the nut to the middle of the 12th fret?

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

if you are going to do this sort of work you should get a 36" rule graduated in 0.01". cheapest i've seen is enco.

but, as 3/16" = .1875", and allowing for error by measuring in 16ths, and compensation, this would be borne out by the 12th fret measurement it sounds like you have a 25" scale.

Hello Colby

The way I do it is to take a straight edge from the nut position to the Center of the 12th Fret mark this on my straight edge, then I add my compensation and position the end I had at the nut position on the center of the 12th fret and where the compensated mark falls on the bridge is the center point for my saddle slot.

I should have mentioned all this takes place on the center line of the neck.

Hope this helps

Thanks for the help guys!

Russell, this sounds like a good way to do it, going to try it later. Thanks!

i would recommend that all measuement be done fron a fixed point, the nut. trying to hold the end of a rule on the exact center of a fret crown while marking at another location is just inviting error.

Ok, let me understand this, using this method to determine an unknown scale length, half of the scale is found by measuring from the nut to the -MIDDLE- of the 12th fret, and not to the actual 12th fret?   And, then multiplied by 2, plus an amount added for compensation, is that correct?

Thanks!

Jeff

Jeff, the term fret has been sort of used as both the fret wire and the space between the fret wire. When they say "middle of the 12th fret" they are talking about the middle of the fret wire.

Jeff Apologies for the confusing terminology, Paul is 100% Correct.

Michael I find this method pretty acurate as you are only working over a distance of half the scale length, but I guess its horses for courses, every one has their own favoured methods.

Cheers

Measuring from the nut to the 12th fret doesn't always work. Buzz Feiten and Earvana tuning systems use a compensated nut. Get a fret calculating program and measure between two adjcent frets. Enter some standard fret scales until you get a match.
Mike Mahar38524.6682523148

Measure from the nut to the middle of the 12th fret. Then double that number. Measure from the middle of the 12th fret to saddle and compare. If there's a difference it might be compensation OR it could be that someone (Taylor does it too...I'm told) lobbed of some distance at the nut. But this would be my guess if the scale lenght came up short. NEXT, divide the closest scale lenght by 17.817 to the distance from the nut to the middle of the first fret. That is the calculated distance for the scale you suspect this one to be. If it's off a few thousanth's that's expected because the nut slots are almost always off( I guess they just didn't worry too much about that for some reason). Any way if that is close then you know the scale they were trying for. You can also compute the next fret distance by subtracting the calculated 1st fret distance ( nut to middle) from the scale lenght and again dividing by 17.817 that will give you the distance to the second fret. When messuring make sure you measure both frets first and divide by two to get the middle. Sometimes fret wire is not the same thickness either.

If this totaly confuses you, smash the guitar into a thousand pieces put it is a small box and mail it to Somogyi. He will, for a fee, tell you the exact scale but it will be in sugar cubes so you will have to translate. ...it's a joke!

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

[QUOTE=Dave-SKG] If this totaly confuses you, smash the guitar into a thousand pieces put it is a small box and mail it to Somogyi. He will, for a fee, tell you the exact scale but it will be in sugar cubes so you will have to translate. ...it's a joke![/QUOTE]

He'll also put it back together, shape the braces, voice the top, add some inlay to beautify any defects and send it back in a couple of weeks, or so. The man's amazing!

Carlton

You could do all this measuring and "maybe" get it right, OR, you could pick up the phone, call Gallagher and ask them what scale length they used on this particular guitar. I'd vote for option #2.

Yea...I agree with the call/Paul... except maybe someone made a mistake or used a bad rule or whatever. Remember all those old gibson and martin rules that were/are still being used? I always measure to make sure I know what it is I am dealing with. Plus, I keep a log of every repair. It's nice to have the info in the journal for future reference.

Then again I might be already on the phone with M.F. ordering some of those $39 specials!

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"