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I am curious to start utilizing a 12-hole classical guitar bridge. I am thinking that the second set of holes should be above and offset to the first. I am going to use a 58mm spacing how much should the second set be offset and how much above.

Ciao
Eugenio DiLampo

Hi Eugenio,

I suppose most builders use a very similar hole layout. If you put / draw it on paper it will come ...naturally. What you want is enough meat above the upper hole. If you drill it too high you might compromise the strength of the tie block. The lateral offset: you can go as far as the middle of the distance between the string holes. Or place it at about 1/3 of that distance. Here is a pic with the bridge of my first guitar.

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Build log

I agree with Alex !
of set is best!
I've tried putting the holes 3mm apart & side by side -it confused the guitarists as which hole to use.

I use the 12 hole and a 18 hole now all the time.
There are some pics on my site but they do not show the tie block from the back like Alexs pic.

I've had to make many nylon strung guitars bridges into 12 hole ones just to be able to lower the string height !
I now can do it without removing the bridge.
It's the most sensible repair to do -not like shimming the fingerboard as done in the past!

try it-you'll never go back to a 6 hole tieblock!
Mike

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Mike Collins

I use 12 hole bridges as well -- I like the fact I can get the strings anchored lower in the bridge. Mike ... how do you use this to lower the string height on a guitar with high action, assuming no saddle left? Are you also trimming the bridge height?

Thanks!

Jim

I don't want to presume to put words in Mike's mouth, but I assume he means that on some guitars lowering the string height would so reduce the break angle, it would be detrimental to the mechanical connection between the strings and the soundboard. By changing to a 12 hole or 18 hole bridge, you automatically increase the break angle by removing the loop under the strings in front of the tie block, which raises the string by somewhere in the 1+mm range, reducing the break angle by that much.

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Waddy

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Sound Clips of most of my guitars

Yes, understood. I was thinking of the frequent situation where the action is too high for the player, but there is no saddle left to lower the string height. A mistaken premise on my part.

Thanks!

Jim

Alex;
Waddy has it right!
Sometimes I have to lower the SADDLE block after the string angle is better.
Sorry to take so long to reply!
Thanks Waddy!

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Mike Collins

Do I get a Tub-O-Lard?

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Waddy

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Sound Clips of most of my guitars

How about a bottle of single malt?

Mike

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Mike Collins

I made a couple of extension drill bits to do this on existing guitars...drill holes about 3/8" deep into one end of a piece of 5/32" brass rod on a lathe to keep everything concentric. I made 1/16" and 3/32" versions. You can do whatever size you want. Peen and superglue the shank of the bit into the hole.

The 12 hole bridge design is really good, especially when using undersaddle pickups.

That's the way to do it right Rick !
My first attempt -that worked great was a 3/16 dowel to hold the bit.
The old buggar still works great!
I protect the top with a old piece of .020 pickguard material!!!

You have such a well of guitar knowledge!
I read all your posts expecting great advise and ,I'm never disappointed!

Thanks for sharing with us all!
Mike

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Mike Collins

Changing the subject with a crowbar, but have you seen the deal Woodcraft has on a box of brad point bits. Something like 110 bits from 1/16 to 1/2 with multiples of each size. I bought a box of them just to get the 1/16" brad points. I think it has about 10 or 12 each of the ones in the small sizes. Small sizes are in increments of 1/32". Only a few, each of the larger ones. The box was something like $26.95.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars