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Hey guys, I am having some issues mounting my bridge. I just got done buffing my guitar and was getting ready to glue the bridge down when I noticed that I may have a layout issue. Ok what is the proper distance from the end of the fingerboard to the center of the saddle on the treble and bass side? Also does the string gauge I plan to use have an effect on this distance? This is for a 25" scale length guitar, I plan on using 10`s for strings, and the measurements I have for it now 25 3/32 on the bass side to center, 25 in the center of the neck, and about 25 1/32 on the treble side. I tried the calculator on stewmac and it has a me a little confused. Any help will be appreciated.

Robbie

Two times the distance from the nut to the twelfth fret plus 0.15" to the front edge of the saddle (in the middle -- between D and G strings). For a true 25" scale (e.g. 12.5" from nut to 12th), that's 25.15" to the saddle. Read Cumpiano's "Guitarmaking" book. It's all in there and it works.

I don't know how your saddle can be at 25" in the center but more than 25" on both bass and treble unless the saddle is bent. That would be a bad thing.

I don't know how your saddle can be at 25" in the center but more than 25" on both bass and treble unless the saddle is bent. That would be a bad thing.[/quote]

I am sorry about my treble side measurement was off a little. My concern is more of the angle of the saddle because I routed the 3 mm angle for the saddle slot according to the stewmac calculator. I am concerned that it may be off, according to my measurements on the treble and bass sides of the saddle. I am right in the center as far as saddle location goes,but have concerns as far as the bass and treble sides go. What would be the correct distance from the edge of the fingerboard to the center of the saddle on the bass and treble side?

Robbie,

The Stew Mac calculator is pretty straight forward. It gives a measurement of 25.087" from the nut on the treble E and 25.21" for the bass E (did you set the calculator for an acoustic guitar?). Converted to fractions, use 25 3/32" on the treble and 25 7/32 for the bass. That will be very close but you'll have to fine tune the saddle depending on how accurate you want the intonation. Remember to measure from the fretboard side of the nut to the center of the saddle.

Steve

I suppose I am confused because I routed the same 3 mm angle saddle slot as the bridge that stewmac has for sale and then measured to the center of the bridge to 25" which left me at 25 3/32 on the bass side. So it seems to me I need to keep the same angle and make a new bridge that has the saddle shifted back and 1/8?

If you have already stripped the finish to glue down the bridge, then making a new one with the saddle moved to the correct spot would be a good option. Have you drilled the string holes trough the soundboard yet?

Steve

Nope not yet. Do you guys drill the holes for the bridge pins prior to gluing it down? I really appreciate your help people like you on this forum are the very reason why I now subscribe to it.

Robbie

Robbie, One thing to be really clear on, when "the centre of the saddle" is referred to in the stewmac calculator it does not mean the centre of the bridge but the centre of the saddle slot across its narrow width.
Be careful, different authors quote compensation figures to different locations on the saddle and it is not always clear which they are using
If you have set the centre of the bridge (either front or middle of the saddle) at 25" you are way too far forward and unless you are prepared to accept a bridge with a lot of bulk in front of the saddle, you are facing repositioning the bridge.
It is much easier and more accurate IMHO to measure to High E and Low E using the stewmac numbers, rather than midpoint and try and get the angle right

[quote="lespaul123] Do you guys drill the holes for the bridge pins prior to gluing it down? [/quote]

Some do, some don't. I use the two out side holes for my bridge clamp.
If you had drilled the holes through the soudboard, you would have the additonal fun of patching them. Your new bridge with it's new saddle position will require the pin holes to be farther back on the bridge to keep the relation to the saddle slot. Otherwise the string break angle over the saddle would be too steep.

Steve