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I am starting to brace my first top. The only issue is, as I have gone for a 24.6" scale length rather than the 24" in my plans I have to make a few changes (I think...) or otherwise the bridge plate will be in the wrong place.

Basically, how do I work out where the bridge goes. I'm guessing there is an exact method to work out whee it goes on the top other than using a 3ft rule. On that. Any advice would be great

On a side note, I am using rosewood for my bridge plate. I assume that is okay, but how thick should it be?

Once you have the scale length, you need to know how many frets there are on the neck: is it 12 fret, 14 fret, or something else? If it's a 12 fret neck, then the _theoretical_ saddle position is exactly 1/2 of the scale length from the upper edge of the body. So, for your scale on, say, a 12-fret 000, the saddle would 'want' to be 12.3" from the edge if there were no compensation. I usually just go with this number, since my bridge plates are wide enough to allow for a fair amount of 'wiggle room'. You could easily enough factor in some reasonable amount of compensation and go from there.

If you're using a 14 fret neck, then you need to find out how far the 14th fret is from the nut, and subtract that from the scale length to get the distance from the body edge to the saddle. If you have the fretboard in hand you can measure it. If not, you can find a table of fret distances, or generate one using a spreadsheet or one of the fret calculators, and go from there. The program I wrote up does the subtraction automatically, and prints out both 'nut to fret' and 'fret to bridge' distances, which makes life easy in that respect.

Thanks for the reply that makes sense. The bridge is compensated, so I assume I measure 12.3" to the middle of the bridge.

In your title you talk of "bridge position", yet in the body of your thread you speak of "bridge plate" in the first paragraph, the "bridge" in the second paragraph and "bridge plate" in the 3rd paragraph. I assume you must be trying to locate both the bridge plate and the bridge, but it is not clear. You should easily ave enough wiggle room in locating the bridge plate. As Allan pointed out, your bridge design should allow for some wiggle room for locating the saddle. There is an important point here. Namely, its the saddle that you really have to make sure ends up in the exact location which is what I believe Allan was saying.

If the bridge is close, your "wiggle room" on the saddle allows it, as Allan said, to be located correctly. This can be done by routing the saddle slot after the bridge is set. It can be done by measuring the sound (notes) instead of just the nut (or 12th fret) to saddle distances.

Ed

Sorry,

What I mean is as I am going to be bracing the guitar, I need to know exactly where the bridge itself will go, otherwise the plate may be in the wrong place for when I glue the bridge on at a later date.

It's hard for me to explain as I haven't done it before.