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Old 07-16-2016, 06:29 AM
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SprintBob SprintBob is offline
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Default Bridge Height

So I did a measurement of the bridge height on five of my favorite guitars and found the following (note the measurements were all the same at both the low E and high e strings):

Collings OM1AH - 8 mm
Taylor 522e 12 fret, 812ce 12 fret, GS-7 - 7.5 mm
Robinson 12 fret sloped shoulder dread - 10 mm

The reason I did this was because on my Jake Robinson 12 fret dread, there is very little saddle showing on the treble side of the saddle and initially I was concerned it might need a neck reset. But when I verified the top of the sound board was essentially flat and the neck was straight, I focused on the bridge and it appeared to be taller than my other guitars which was verified with the measurements above.

The guitar plays great and sounds wonderful and there are no intonation issues even with the relatively slack break angle on the treble strings. I'm not going to take any action on this and the saddle is set up to give me the action I like for playing the guitar.

What are the guidelines or practices a luthier might use in establishing how tall he/she would want the bridge to be on a specific guitar? I've not specifically addressed it with Jake yet. I'm the 3rd owner of this 2009 custom built guitar and my guess is the original owner spec'd out a relatively high action.
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Doerr Trinity 12 Fret 00 (Lutz/Maple)
Edwinson Zephyr 13 Fret 00 (Adi/Coco)
Froggy Bottom H-12 (Adi/EIR)
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Rainsong APSE 12 Fret (Carbon Fiber)
Taylor 812ce-N 12 fret (Sitka/EIR Nylon)
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Old 07-16-2016, 07:47 AM
tadol tadol is offline
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Thats a question that you really need to ask the specific luthier. Some of the factory builds keep bridges on hand of different thicknesses and use the one that gives them the height they want when they lay a straightedge on the fretboard. Others make the bridges tall, and sand them down to the height they want.

Bridges are interesting things - they are the only visible top brace, they are the anchor point for the strings, they have to hold the saddle upright, they add mass to the guitar top, and with all the functional aspects, they are also a defining element for the aesthetic style of a guitar.

Each luthier (probably) treats the bridge differently, depending on how they prioritize the many qualities it must have. I would ask Bruce Sexauer about how he treats bridges - I learned quite a bit watching him make 2 or 3 different bridges for one guitar, with the concern about getting enough surface area to hold it on, the height needed to get the action he wanted, and then getting the mass just right, adjusting it to get just the right weight for the top thickness and bracing size/shape he'd used. I'm sure other builders have similar concerns, and prioritize these things differently. After all, this isn't science -
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Old 07-16-2016, 08:08 AM
Tom West Tom West is offline
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Some makers aim for about .5" for the distance of the low E over the top at the bridge. Then bridges are made in the .350"-.375" area leaving about .125" height of saddle.
Thick bridges add weight,subtract responsiveness and in my mind tone. Some may like a bit of weight to help add bass but that is not my cup of tea. Weight is also controlled by species of wood for bridge. Species can also control damping and this may be used to help trebles that have problems. Just my thoughts but others most likely have others.
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Old 07-16-2016, 10:31 AM
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Collings OM1AH - 8 mm (0.315")
Taylor 522e 12 fret, 812ce 12 fret, GS-7 - 7.5 mm (0.295")
Robinson 12 fret sloped shoulder dread - 10 mm (0.394")

I converted those measurements for those of us who don't work well with metric.

Pretty much as Tom says, you'll find various approaches by different makers, but I don't typically like a heavy bridge. Martin's typical bridge is about 0.340" with a saddle around 0.150", for a total height very close to 0.5". Vintage Gibson bridges are much thinner, so the total string height off the top is less. My Proulx bridge is right at 0.300" and flat on top, but with a tall 0.200" saddle. Mario moves the saddle back away from the front of the bridge enough that it is stable even with a tall saddle.

All that said, I would think your tall bridge could come down quite a bit and improve the response and geometry. You do have to be mindful of the saddle slot depth when shaving a bridge, but that's nothing a good repairman can't handle.
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Old 07-16-2016, 10:37 AM
mercy mercy is offline
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Tom has it correct, 1/2" string to top is ideal but the geometry of the neck to the guitar comes out differently on each guitar. Bridges with less damping will give you more of the guitar's potential. So the bridge should be as close to 3/8" as possible with a saddle reveal of 1/8" over any true rosewood but East Indian.
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Old 07-16-2016, 11:37 AM
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Here's better measurements on my Robinson dread which is spruce top and mahogany back-sides:

At low E:

Bridge height = .375"
Bottom of string height = .5"
Amount of saddle visible = 1/8" or .125"
12th fret action = 3/32" or .9375"

At high e:

Bridge height = .375"
Bottom of string height = .4375"
Amount of saddle visible = .0625" or 1/16"
12th fret action = 5/64" or .078"

As I stated before, the ease of play and tone are excellent to my body and ears so I'm not motivated to really change anything at this point.
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Doerr Trinity 12 Fret 00 (Lutz/Maple)
Edwinson Zephyr 13 Fret 00 (Adi/Coco)
Froggy Bottom H-12 (Adi/EIR)
Kostal 12 Fret OMC (German Spruce/Koa)
Rainsong APSE 12 Fret (Carbon Fiber)
Taylor 812ce-N 12 fret (Sitka/EIR Nylon)
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Old 07-16-2016, 11:44 AM
murrmac123 murrmac123 is offline
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Quote:
Originally Posted by mercy View Post
So the bridge should be as close to 3/8" as possible with a saddle reveal of 1/8" over any true rosewood but East Indian.
I may not be the only one who is slightly confused by what exactly you are intending to say there ... you surely don't mean that East Indian rosewood isn't a true rosewood ( it is in fact a true dalbergia) ... are you then saying that for some reason an EIR bridge should have a different height than 3/8" ?
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Old 07-16-2016, 08:18 PM
mercy mercy is offline
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Sorry I confused the thread by inserting information that should be in its own thread. Yes EI is a true rosewood but it is a high damping rosewood so I was meaning I like rosewood better than ebony which is even higher damping but I prefer some other rosewood than EI. No it should not be a different height.
Thank you
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